What are your thoughts on the phrase "No replacement for displacement"?
Posted by Lightning_Of_Fate@reddit | askcarguys | View on Reddit | 210 comments
Is it still valid in 2024?
QubeRewt@reddit
The overall power of an engine isn't the size of the displacement, it's how much fuel and oxidizer it can consume and the percent that it can deliver to the rotation of to the output shaft. There's a reason the proper term is "throttle" not "gas pedal". I comes right down to how much energy the engine can throughput. Naturally, a larger combustion chamber will lead to more fuel and oxidizer coming in sans turbo or super, but that has it's own problems. I.e. larger moving parts, larger angles, more mass moving, etc. It's all about how much oxidizer (oxygen, or nitrous if you feel froggy) you can get going in, nothing more, nothing less. Anyone who tells you different failed physics. Now, that said, how you get that power to the ground is a different animal and a different question.
1PistnRng2RuleThmAll@reddit
What matters is how much air you can displace in a given amount of time.
Displacement, super high rpm, and turbos are all methods of moving more air per minute.
1PistnRng2RuleThmAll@reddit
test
Dazzling_Ad_2939@reddit
Lol, F1 cars make 1000hp from 1.6 liters of displacement. The slower NASCAR engines are 5.8
mytoiletpaperthicc@reddit
The F1 motor wouldn’t last half as long honestly. It costs millions more in r&d to produce that.
In the real world with modern car tech, the higher displacement motors are generally the ones that are faster and more capable of holding high hp without sacrificing reliability.
Sure my little v6 can keep up with a v8, but that doesn’t change the fact that each cylinder in the v8 undergoes less stress than each cylinder in the v6. With that argument, the really is no replacement for displacement.
There are obv exceptions to this rule as you highlighed with f1 but in the real world on the street with our regular car tech, the bigger displacement guys usually win. If not in power then in high RPM power and if not that either, then by reliability it is better built to withstand constant high hp.
Longjumping-Many4082@reddit
Back in the day, when turbos and superchargers were rare, it range true for the most part.
But GM disproved this when the Buick GNX (turbo 3.8L) was faster than the flagship Corvette running a 5.7L V8.
Hydraulis@reddit
The laws of physics haven't changed. It is still by far the least expensive way to increase output, all other things being equal.
sohcgt96@reddit
Yeah, I'd agree here. Making a larger displacement engine really isn't that much more expensive. But efficiency... that's the complication. Big engines are big all the time.
Heavy_Gap_5047@reddit
Variable displacement systems like the MDS system in the Hemi have changed that.
SkylineFTW97@reddit
Problem is there isn't a single cylinder deactivation system that isn't a piece of shit.
DOD/AFM eats lifters.
I think MDS does the same.
Honda's VCM doesn't, but it gums up piston rings and causes severe oil burning and the vibrations also prematurely kill engine mounts and torque converters.
Heavy_Gap_5047@reddit
MDS doesn't eat lifters, there's been lifter failures but the cause isn't related to MDS.
SkylineFTW97@reddit
I don't know as much about MDS as the other 2, so I forgot exactly what it was. I'm a Honda tech, so I know all about the VCM induced failures.
Heavy_Gap_5047@reddit
I don't know much about VCM.
Best of my understanding DOD/AFM and MDS are very similar. That the lifters work the same, but MDS is a little better in that it doesn't use an oil manifold, it's in the block. And MDS has 4 solenoids to time the change over better vs the one in DOD/AFM.
If I had to guess though I think the cause of the lifter issues in both DOD and MDS are identical. That it's not actually the DOD system, but a lifter quality issue. I don't know for sure but I'd wager that both Chrysler and GM get there lifters from the same supplier.
sohcgt96@reddit
Well, they changed it a little. They didn't entirely fix the issue. Reliability issues aside, its only squeezing 1-3 MPG more out of most vehicles but that's because you're mostly talking trucks with the aero of a brick. It just takes X amount of power to move them through the air at a certain speed and there is only so far you can take it before your just run head first into physics.
Now my Grand Prix GXP had that and it did make a really big difference if you drove it right, it'd jump from 21-22 MPG to 28-29 when the DOD kicked in. Trouble was you had to be going the right speed, not too windy, not uphill or anything like that. Because its an on/off system vs variable load like a smaller turbo motor, its not very progressive and if you're not in the right conditions it just doesn't do anything. But for a car with a 5.3L V8 I pulled some really good mileage on a couple road trips with it and it was an overall great car until about 130,000 miles when just everything started to fall apart. If that car had a 6 speed instead of 4 speed auto with a little better gearing it would have taken it from good to great but a transmission up to the task with that many gears just didn't exist in the parts bin at the time.
Heavy_Gap_5047@reddit
I can't speak to the details of your DOD in the Grand Prix but the Hemi MDS does modulate well. The magic comes together when it's combined with an electronic throttle, variable cam timing and a capable PCM.
The engine will use cam timing to modulate power some so that it can keep the throttle open more yet produce the lower cruise power levels and sip fuel. The big benefit of this besides the MDS is that it minimizes vacuum reducing pumping losses in the engine. Then of course this cam timing and throttle work together to modulate power.
I barely notice when the 4 cylinder mode is activated in mine. There's a light that comes on and on cars with loud exhaust it can be heard in the note.
sohcgt96@reddit
That does sound like a better system overall. The GM system just opens some solenoids in the valley to cut oil pressure to the lifters and then shuts off the injector to that cylinder, that's about it, granted that's the 2006 version so nearly 20 year old tech at this point. The EcoTec V8s may be a little more advanced than that but since I've never owned one, never bothered looking much more into it.
mrsclausemenopause@reddit
Absolutely as long as you use the basic formula (Displacement x Volumetric efficiency x RPM)
Basically, how much displacement times how much of that space you're using witch is less than 100% for NA engines and greater than 100% for forced induction, then how many times a minute you can do that.
Or even simpler. How much air can your air pump pump over a minute.
ryandenney347@reddit
The replacement is boost.. I'd take a 302 Ford turboed making 500hp over a 400 cid motor at 500hp.
Smooth-Apartment-856@reddit
Well…now Ford makes a NA 5.0L making 500 horsepower.
But a NA 400 cubic inch 500 horsepower motor will be making that power with lower cylinder pressure which means lower octane fuel can be used, less stress on the rings, valves, head gaskets, et cetera, and the 400 CID motor will likely have bigger, beefier crank, rods, main caps, and so on.
What is it about a smaller boosted motor making the same power that you like?
TraditionalBidN2O4@reddit
Less Weight. Better fuel economy. Better handling. In almost any application outside of drag racing, balance is more desirable than raw power.
01WS6@reddit
In the above comparison the 5L would be physically bigger, heavier and get worse gas mileage. Displacement doesn't represent physical size, weight, or gas mileage.
[6.2L on the left, 5L on the right](https://www.svtperformance.com/attachments/jghig3p-png.1430076/
ryandenney347@reddit
Getting 500 HP na out of 400cid is no small feat. You'd still need to rev it past 6500rpm. 230 degree at 0.050 lift or larger cam, single plane intake, and some head work. Also will require a 3k stall converter assuming an auto trans, won't idle below 800 rpm in gear. Street manners will suck.
The new 5.0L has 60 years worth of advancement over old pushrod engines. Guy are adding turbos and blowers to the 5.0 and putting down over 1000 HP on stock motor setups. They are also spinning the motor to 7000 and higher rpm.
Heavy_Gap_5047@reddit
Not really, a factory 6.4 Hemi is nearly there, 392ci and 485hp. That is not a highly stressed or high revving engine.
ryandenney347@reddit
What's your definition of high reving? Found the 6.4 spec and peak power is at 6100. So you could spin to 6500..
We need to separate 60, 70, 80, and 90 engine designs from what we have today. The OP question about a replacement for displacement came from those decades 30+ years ago.
Heavy_Gap_5047@reddit
You used an example of 6500, the factory 6.4 rev limiter kicks in at 6400, and peak torque is at 4200.
Pretty sure the phrase is far older than that. Physics hasn't changed, all modern tech has gotten better at is making high HP/CI with less downsides. The high performance engines of the 60s made great power and even got decent MPG, they just did so with horrible emissions.
Smooth-Apartment-856@reddit
Getting 500 horsepower out of a 400 cubic inch engine isn’t really that hard, it can run on pump gas, and be very streetable, all with off the shelf parts.
Start with a Ford 351W block, and a 4” stroker kit with .030 over pistons. Good flowing aftermarket aluminum heads. Something good like Trick Flow or AFR. Don’t get the cheap Pro Comp or Speedmaster stuff.
You can still use a streetable hydraulic cam, but you’ll want to use a hydraulic roller. Keep the duration on the moderate side so you don’t kill low end torque, but take advantage of the roller lifter technology, and go for as much lift as you can get away with. The moderate duration high lift roller cam and heads the old timers will tell you are too big is the magic formula. A good dual plane like Edelbrock’s RPM Air Gap, and whatever 700-750 cfm carb you are most comfortable tuning will round out the combo. Compression in the neighborhood of 10.5 to 1 with the alloy heads will still let you run pump gas.
500 horsepower from a performance built small block isn’t the big deal it was 20 or 30 years ago.
There are similar recipes for Chevys and Mopars as well. Nothing all that magical about one make of engine or another.
Heavy_Gap_5047@reddit
My god why? That's totally backwards to me.
ryandenney347@reddit
A NA 302 only needs to make 250 streetable HP before adding 15 lbs of boost. Will idle in gear at 650 rpm, all in by 5500 rpm. Still gets 20mpg on the freeway. Simple and easy to maintain. Boost just makes it easy to get more HP without spending a bunch of money.
Heavy_Gap_5047@reddit
What... I have no idea why you think that's an answer.
A 302 with 15psi of boost to make 500hp would have to be low compression and run high octane fuel. Sure it wouldn't need a lot of cam, but neither would the larger displacement high compression engine and variable cam timing has made that detriment rather moot anyway.
A high displacement NA engine making the same peak HP can be higher compression making it more efficient with more off idle/low rpm torque, no turbo lag, and less need for more expensive fuels.
ChainOut@reddit
Outdated trope
DarkLinkDs@reddit
It's a hold over from many years ago.
Now-a-days forced induction is a perfectly suitable replacement for displacement. That is why crossovers and smaller suvs and even now some trucks have smaller and smaller motors making the same or more Hp/Tq than previous bigger C.I. models.
That being said a bigger motor does "usually" make its power lower. For instance a 454 that makes peak torque at 3200rpm vs a 2.0T ecotec making peak torque at like 5000rpm. (Just loosely based numbers)
Heavy_Gap_5047@reddit
Unless one cares about engine life or efficiency under load.
DarkLinkDs@reddit
I guess you'd have to talk that over with diesel guys.
Heavy_Gap_5047@reddit
Diesel is a whole other thing, but no replacement for displacement still holds true.
That's unlikely to be true unless you have a particularly poorly efficient 454 in a bad application.
DarkLinkDs@reddit
Even on a good day unloaded a late 70s-90s 454 gets 10 mpg and maybe 8 towing.
Almost all of them made less than 250 hp and less than 400tq.
That's 20 years of dually and HD trucks barley getting out of their own way.
If we are talking drag only vehicles sure "a" built big block may have an advantage however 90% of people dailying or towing don't have to fully build their engines to make them effective.
Diesel is not a separate thing. Displacement plays a part there just like a gas engine.
Just like in heavy equipment like the CATs my job works on and all the other industrial equipment that relies on forced induction for the entire life of the service of the machines. Some of them have been running for decades.
Heavy_Gap_5047@reddit
Post EGR to pre-vortec 454s aren't very efficient sure. But modern stuff doesn't do much better in those applications and you're only considering MPG not cost.
Of course displacement plays a big part in Diesels, I said that. But turbos work completely differently on a compression engine than they do on a spark engine. If you work for CAT you should know this.
DarkLinkDs@reddit
Oh no I'm considering the vortec 454s, tbi 454s, and carbed 454s. I'm in the forums.
Cost to maintain, modify and rebuild is typically higher on the big blocks compared to something like say a 5.3 LM7 for instance. The newer 2.7T engine in the silverados has more torque than both of these engines and makes it at about 3k rpms. Average 5 year costs seem to be around the $2500 mark on the 2.7 which isn't bad. The newer ones have also had some issues addressed and seem to be handling the tq fine.
Whereas something like the 3.0 duramaxes are about the same costs as the bigger 6.6 duramaxes to maintain.
As far as working with CAT, I dont anymore but the convo was about "replacement for displacement" and turbo engines have long long been shown to be reliable for a couple decades.
You can't count cars like Subarus that like to pop their head gaskets all the time or some poorly maintained 40 year old lagging turbo sedan.
Tech has come a long way and allot of the teething problems have been solved or mitigated despite the bean counters forcing cheaper and cheaper quality.
Fwiw--- I'm a v8 guy all day and love all my old engines, my LS engines, and our equipment. I do however also realize what is out there. Also FWIW I have a 2.0T awd CTS that performs flawlessly whether I'm trying to get 35+mpg on the highway at 70 or carving corners on the old back roads on my track tires.
Heavy_Gap_5047@reddit
Do you understand the differences between those engines? The effects of NOx regulation and what was done to deal with it have a huge effect and each generation is significantly different. It also all changes with some smart mods. A big block chevy can absolutely average 30mpg, I've done it, just not stock.
Cost wise you only appear to be considering light duty applications and short time frames. While a big block will be more expensive in some ways they also last a lot longer and are more efficient when worked hard in heavier applications.
In a half-ton pickup just used as a commuter, left stock, bought new, and only owned for a short period, sure little stuff works. But they're highly stressed engines that won't last long, most of all under high workloads, and aren't efficient under high work loads.
I already said turbocharging works very differently on Diesel engines. Do you not understand that?
DarkLinkDs@reddit
I think you're the one that doesn't understand. You are reaching for things like 30mpg big blocks.
You'd be the only guy in history to do so.
I'm considering the average costs over a given time frame. I'm considering machining costs for cylinder head repair vs replacements, I'm considering wear items like the cam and lifters, I'm considering oil changes and fuel consumption.
I'm considering everything when I'm talking about each engine.
You seem to not understand the differences between the engines and the whole reason I mentioned them.
"Replacement for displacement"
There is a reason we don't use the BB anymore or even the 8.1 vortec. They do not meet the demands that the smaller engines do for the cost. Whether upfront or in the long run.
They spent millions to research this very thing. They will not be swayed by one guy on reddit who supposedly averaged 30mpg with a BB.
Heavy_Gap_5047@reddit
If you were honest you'd just call me a liar, it's been done and I'd be far from the first to do it. That you don't know that it's doable or how says everything. With current aftermarket it's really not even that hard, just expensive. Takes a total rebuild, aftermarket heads, aftermarket EFI, etc. And for similar goals unless big inches are called for the Apache Hemi would be a better choice anyway to take advantage of the variable cam timing, great factory heads, better stock PCM, active intake, and MDS.
I'd happily wager that I could get a Chrysler 300 to 40MPG.
They have to comply with NOx regulations, I would not.
DarkLinkDs@reddit
I'm honestly interested in the original topic and not fairy tales.
I've never once seen or heard of anyone getting 30mpg from a 454 in any articles. None of the EFI articles, no website, no forum posts, nothing.
Most commonly guys are struggling to even reach 20 mpg.
Most I've seen is a guy with a 468 get 20mpg in a completely custom rig for this purpose that would spin 1950rpm at 70 or so. He was using a 700r4 with a 3:07 12 bolt.
Most he ever got was 21 at 55 or so.
You would be more believable if there was proof of anyone else ever getting the same as you.
However......this also falls into the "costs" talked about earlier where at this point you are completely rebuilding a 454 for the purpose of mpg and adding expensive items like an actual decent EFI system which are not cheap. I should know, I'm gonna be running a 4 barrel efi setup soon.
If you get the chance you might as well submit your info to a few of the forums and let the old guys be amazed by your planning.
A Chrysler 300 and a modern hemi do not in any way equate to the work needed for the 454.
But if you do make a 40mpg 300 then cool, you can start converting all of them and make big bucks. I'll watch your TV show.
Heavy_Gap_5047@reddit
I don't know what to tell ya, I can't make you look, understand, or believe me in this format.
Few people make MPG a goal in the build of a 454. Most are after power, sound, coolness, or whatever they think is important, but MPG is rarely a primary goal and when it is it's in tow rigs where they'd never reach that MPG for other reasons and these days are going Diesel.
I did it a couple times for customers who had goals that aligned with it, but few do.
Let me ask this, I think so far we've assumed pickup, but I'm curious, would you believe a C3 Corvette with a 454 could get 30MPG?
Well yes, costs are a big part of why few do it. The big $$$ it'd take buys a lot of fuel and few willing to spend the money really care about MPG.
I don't think a forum would have anything different to say than you.
Yes I very much agree that it'd be far easier with a modern hemi, that's why I said it. Did you not get that? Well that and I'm doing it anyway with mine, so if you took me up on the wager it'd be all good.
The 300 aftermarket isn't any different, people want Hellcat engines, superchargers, etc. Supercharging and MPG are contradictory.
Really I think the only way to prove this to you would be for you to take me up on my wager or pay me to build one for you.
DarkLinkDs@reddit
I'm specifically referring to guys over the past 20+ years on forums asking for mpg builds with there 454s. Chevelles, elcos, nomads, Monte Carlos, lightweight swap projects, etc
I'm not sure how you did not understand that. I am not assuming in a pickup, and I am not assuming an old th350 or th400 non overdrive trans.
The mpgs I quoted you earlier were from a guy with a car. Whether it was a chevelle or elco or whatever I do not remember. He was using an OD trans and 3:07s as per his own info.
You can Google 454 mpg builds and find a general consensus. I was looking up the same thing 10 years ago. I still look up the info every couple months.
My buddy has a 350 powered c3 convertible and he doesn't even get half of your BB numbers with no emissions on his vehicle and free flowing exhaust. (1969 car with a very ancient fixed headlight setup and one piece hood/fenders)
As far as the hemi, what I didn't get was why it was brought up at all. If we are talking modern motors then I absolutely CAN make a 40mpg LS1 car. Stock with a tune. Best part is there is proof. Also LegitStreetCars on youtube made a video of his 40mpg c5 corvette.
That I can get behind.
Not a 30mpg big block.
Also id think proof would be how you prove this to people. Not telling them to donate to you but nice try.
Based on your trailer ideas for your 300 I have even less faith that you were being serious and that this has been some weird troll session this entire time.
What you gain from this waste of time idk, but if anything all you really did was confirm what folks already would be thinking reading your comments.
Heavy_Gap_5047@reddit
I don't see why you'd think I'd give away my knowledge for free on forums. Why would I spend time convincing others that I'm right while giving away hard won knowledge. Frankly I've said enough in this thread already that should give some hardy clues as to how it's done.
You're saying a guy built a BB car with MPG as a goal and only got 21mpg at 55, damn. I could beat that with a carburetor.
Your buddy should hire me to work on his car.
I thought I made it clear why I brought up the hemi, you really need to work on your reading comprehension. "for similar goals unless big inches are called for the Apache Hemi would be a better choice anyway". A customer comes to me wanting big inch V8 power and good MPG I don't suggest building a BBC, I suggest a modern Hemi. I'd only go BBC if there was other reasons to.
I don't know why you think it's doable to get 40 with a stock LS1 and not 30 with a built BBC. How they work isn't that different.
WTF, the proof is the proof, lol.
You've been spying on me, I like my trailer ideas, IDK what you think is wrong there.
Ehhh I'm stuck wit nothing better to do, this shit's more entertaining to me than TV.
DarkLinkDs@reddit
If the knowledge existed it would've long been spread. You haven't really said anything.
Guys who have been working with the engines in car haulers, cruisers, and toys for over 50 years would have long discovered the secrets to 30mpg and would never swap engines again.
I read just fine....your storyboarding is what needs work.
Your statement for the use of the hemi originally was left field as it was nowhere near the displacement nor is it related to the specifics of your original mpg claims. Or for that matter the specific discussion of replacement for displacement.
I'd doubt you'd beat the guys numbers since he actually had a running and driving example and posted his knowledge for free...
Also, buddy would definitely not let you touch his car seeing all this.
Ls1s stock in any car they came in could hit 30-32mpg on the highway in a manual car. So for someone to add a couple pretty neat modifications to tune and driving style 40mpg at the most extreme was completely believable. (8mpg difference)
Saying an ancient engine like a 454 which got 8-12 in almost every vehicle it ever went into, can get 30mpg (More than double) if you and only you touch it is at best absurd.
Not even the EFI companies will make that claim
The Ls engines would be your best comparison to the Hemi not the old BB.
There is video proof, build proof, and plenty of info all over the web to support the LS and now even the newer LT engine numbers. Hence why I linked you the video
There are exactly zero sources for any 30mpg big blocks attached to anything. Your best bet would be shoving a BB into an extremely tiny car and it still wouldn't work.
I had checked your page to see if you built engines or racecars or had any kind of proof of anything. All I found was you trying to understand basic aerodynamics and that alone was kind of the nail in the coffin to your whole story.
I dont really see entertainment here, it's more like a kid says he saw Sasquatch but doesn't have proof. Meanwhile the rest of the world knows sasquatch doesn't exist because it's been thoroughly debunked.
Hopefully OP doesn't have to read this far down to be disappointed
Heavy_Gap_5047@reddit
There's a lot of misinformation around, this is no different.
Stoker kits up to 448ci are commonly available for the Apache Hemi.
Wait, you're only reasoning is that the 454 got low MPG in factory applications, lol. GM never put an EFI 454 in a car and IIRC they never even combined a 454 with an OD transmission in a car.
Yes the LS is a better comparable to the Hemi, so what?
I've built engines for race cars.
Apparently nobody in that aerodynamics sub understood any better than I, so....
Funny, one of the best engine builders I've ever known swore to have seen a sasquatch.
Why would I be disappointed?
DarkLinkDs@reddit
I never said anything about GM putting an EFI BB in a car. I also didn't say anythingvabout them putting an OD trans in a CAR behind one from the factory either.
2 things you've just made up from thin air. I gave you results from a guy with an OD trans, in a car. If you are unable to read that yet again then there isn't much else to discuss.
Why are you now referring to stroker kits or the hemi, when building a stroker hemi isn't even remotely relevant to the convo?
You tried to compare a new hemi to an old BB and getting it to 30mpg, and I gave you an actual modern example to match. I see it confused you some how.
I'm sure you've built engines for racecars if you get so easily confused in a regular automotive discussion /s.
......and....do you really not understand that when I said something about "OP being disappointed" that YOU are not the OP right???.
OP= Original Poster.....
Heavy_Gap_5047@reddit
A baseline that's very handicapped by those facts.
You JUST said "your statement for the use of the hemi originally was left field as it was nowhere near the displacement" did you forget already?
DarkLinkDs@reddit
The baseline supported by those facts. I'm glade we've finally gotten you to at least admit those are actual and factual.
I didnt forget anything. You are talking about building a hemi to then try to compare it to a 454 which then needs to be completely rebuilt by the wizard of OZ to reach a mystical 30mpg.
YOU forgot the 30mpg BB doesn't exist. YOU claimed to be able to make them average 30mpg. But you have no proof, no parts list, no costs, no comparison of metrics vs a modern engine already outperforming said BB, no anything other than "if I fully rebuild it it will get 30mpg".
Taking into account the imaginary amount of money it would take to reach your goals, you'd never recoup what you spent vs using a modern engine. Cost was one of the issues brought up originally. You throw that out the window immediately with a BB
Stemming from the original convo yet AGAIN, in both engines case they are not as efficient as the smaller modern motors in anyway. You've just been talking in circles homie.
coryeyey@reddit
Let's not forget hybrids as well. The electric motors can provide a lot of instant torque that even a V8 will have trouble matching. There is a reason one of Porsche's fastest cars is a hybrid forced induction car. V8's used to have advantages over the competition when just NA, but those days are long gone now with forced induction and electric power being the predominant factor in determining the power of a vehicle. Otherwise you'd look at the 3 cylinder 1.5L in the GR Corolla and assume it was slow.
Andy_Zhang_98@reddit
I drive a Crown Vic P7B, it has only 250 horsepower and has a 4 speed automatic, but every time I accelerate the engine sound and the feeling of it’s torque is something you will never get from a Audi S4, or a Porsche Cayenne, or a Tesla Model Y, which I all drove before, it’s just a unique experience
Leading-Put-7428@reddit
Considering my $300 ebike beats most cars off the line leading to surprised pikachu faces I’d say it’s outdated.
Considering my previous 600cc sport bikes I’d consider the phrase laughable.
Usual-Owl-9777@reddit
It was never valid.
sohcgt96@reddit
I would say it was back in the carb days where there is no feedback of any kind. And there is really some truth to it, if you want to make a lot of power, its always easier to just start with a bigger engine. That doesn't mean its the best way, just the easiest way.
Usual-Owl-9777@reddit
My salient (and evidently unpopular) point is that displacement is 1 measurement from a vehicle. To blanketly suggest this is the only variable that matters is pretty dense. The replacement for displacement is speed.
The only time I've heard this term used IRL is in USA when folks are arguing import vs domestic. It's just general shit talk, nobody believes it.
sohcgt96@reddit
Well sure but lets be honest most people who still use the phrase are, like you said, most likely stuck in the past or dense. Its shit talk and its usually coupled with a moving goal post because even when somebody goes as fast in something with a smaller engine, they'll just change the argument, and it always just comes down to people trash talking something that isn't the kind of car they want.
I'll still stand by my point that when performance is concerned, generally more displacement is an advantage. But its not the only thing that moves air. RPM and boost are the great equalizers and ultimately, you can always run just as fast with a smaller motor. It might be a little harder or cost more but you can absolutely replace the displacement.
Now if you're talking work instead of performance, in heavy duty applications, larger engines are going to have some real advantages in durability but that's not just because of displacement. I'm of the opinion its good to match displacement to weight/load.
datbimmer@reddit
Nice, dumbest comment I've read all month
Usual-Owl-9777@reddit
Love you too sugartits 😘
datbimmer@reddit
<3
ConsistentExample839@reddit
As far as that statement being valid in 2024.... That statement wasn't valid in 1987 when Buick was blistering everything with their twin turbo V6 grand national.
ConsistentExample839@reddit
There is a replacement for displacement, that being forced induction. Sure, there's an added complexity but you can still run an i-4 FI engine at low boost levels and get far better efficiency than a big block engine.
You can run a k-series above 1000 HP and also run it at i-4 fuel consumption levels. A big block v8 will always burn big block v8 levels of fuel.
jrileyy229@reddit
No longer valid.
The_Cat_Of_Ages@reddit
hear me out, turbo big block
Mammaltoes25@reddit
This is the way
Lower_Carrot_8334@reddit
Haha. Internal combustion engine JUNK
jrileyy229@reddit
If money is no object, sure. NHRA engines make 12k HP from 500ci... They just only do it once before they are toast
CoreyDobie@reddit
Twice if you are lucky and feeling spicy
thethirdbob2@reddit
Still Valid
Heavy_Gap_5047@reddit
I'm curious why you think so. I can probably guess what you'll say, but still.
avoidhugeships@reddit
A naturally aspirated V8 just have a sound and feel that is hard to match. Regulations are making them rare unfortunately.
motorboather@reddit
Nah, the boating world will keep V8’s in their place. Torque matters in the marine environment and V8’s are perfect for it.
LifeWithAdd@reddit
This is what I try to explain to people. I love my EV it’s insane fast, the ultimate daily driver, and so much silent smooth power is an experience in itself. But my 69 Camaro is such a raw powerful feeling. You slam on the gas and hear the whooshing sound of the secondaries opening sucking air and smell the fuel spraying in. The car vibrates and shakes as you hear the rear end whine like a jet engine up to speed. You feel the heat coming off the floor and center console from the rumbling long tube headers right below you all while getting sucked back into your seat. Then you let off the gas and hear that tiny bit of unburnt fuel turn in a fire ball and roll underneath you through the exhaust and fire out of the back. It’s an absolutely visceral experience.
Heavy_Gap_5047@reddit
It's sad that so few will understand what it really means to drive an old school high displacement low end torque engine. How smooth and capable they truly are. That one doesn't really need 10 speeds and high redlines when you make big smooth low end torque. Just how nice it is to drive a high compression 500CI V8 with a smooth 3 speed slush box.
SkylineFTW97@reddit
The LS7 was the best of both worlds. High displacement and high compression, but could handle 7000+ RPM. Thing was a monster.
ButterYourOwnBagel@reddit
It’s why I keep my c5 corvette. NA v8s are son to be an endangered species
XtraChrisP@reddit
100% why I bought my RC F and put a nice exhaust kit on it.
Motorized23@reddit
You and me both! Which exhaust did you go with?
XtraChrisP@reddit
INVIDIA. Sounds amazing.
djsnoopmike@reddit
Any Lexus V8 needs an exhaust cause Lexus makes them way too quiet for their 50yrs+ target audience
XtraChrisP@reddit
Sound like someone who's never heard a stock F. You the douche who downvoted a comment about my own car too?
djsnoopmike@reddit
Geez, I don't even know who are, why so aggressive? Just say you disagree
XtraChrisP@reddit
Was just a question. If you weren't the douche, there's no need to be offended.
6inarowmakesitgo@reddit
The last of the Interceptors…
Ultrase7en@reddit
I love that movie, unfortunately it really rings true today
TheWiseOne1234@reddit
My C8 loafs at 75mph and 1,500 rpm in v4 mode. I still can't believe it. That is some reserve power right there :)
Hopfit46@reddit
Sound and feel?agreed. The replacement for displacement is engineering and machining. What comes out of the crate in the average 3.5 v6 would be a 70s muscle car in terms of horsepower.
EnvironmentalGift257@reddit
It’s maddening that it also comes with a POS CVT that lasts 35k miles before grenading.
2005Chevy1500@reddit
Regulations ruined GM’s series of V8s for their trucks. The GM 5.3 was the most tried, true’d, and trusted V8 in the world……. Then they introduced Active Fuel Management (DOD) lifters . And it’s been slowly ruining the reputation since. I daily a 18 Silverado 1500 with a AFM disabler. The day I smoke a lifter or score my cam I’m trading it off for a 03-06 (07) Chevy.
Neon570@reddit
Well, let's put it thus way.
I just pulled a 90s ford 351w out of a parts truck. Had maybe 220hp brand new.
My wife's 3 cylinder, 1l smart car has 95 hp.
It's not the 80s anymore. Engines can do ALOT more in smaller packages now
Beemerba@reddit
I am reminded of my trip to a big motorcycle show in Chicago back in 2002. Harley was introducing their new 1300 cc engine that had 135 horsepower. BMW was introducing their new 1300 cc engine that was rated at 285 hp. That tid bit plus the fact that my Mazda 2.5 liter is rated at 5 hp higher than the 5.7 liter engine in my pickup tell me that displacement is NOT a good indication of power.
JCDU@reddit
HP is a very movable feast, it's torque * RPM * 5252 if memory serves - so big lazy engines that make gobs of torque low-down can have disappointing HP numbers but still be a far nicer and more drivable thing.
Semi trucks may "only" have 300-500hp but they can be making 2000nm+ of torque at something crazy like 1750rpm with the shift point not much further up than 3k, stick a 1000hp supercar in front of a 40-ton semi and try to move it you're going to have a bad day.
What you (mostly) want is area under the curve on the dyno chart - a nice broad flat power band gives a very flexible and drivable vehicle compared to one that has nothing until just before the red line and then makes all the power in one peak.
SkylineFTW97@reddit
This is why seemingly anemic engines like the Ford 300 six can pull obscene amounts behind them. Not much power, but tons of torque and from a super low RPM.
DonkeyTransport@reddit
Not horsepower, no. Torque, yes.
tidyshark12@reddit
That bc power is a terrible way to compare engines. Torque is better.
Power vs weight can be a good way to compare fast vehicles, though.
Heavy_Gap_5047@reddit
That also though really depends on how one defines power. A peak HP number isn't real power. Real power is torque and area under the curve.
thethirdbob2@reddit
Yep, real power is power where you want/need it to be.
coryeyey@reddit
The Toyota GR Corolla is a 3 cylinder that pumps out 300hp. Take any NA engine and add a supercharger and it will be a hell of a lot more powerful than it was before. For many different reasons, it makes a lot of sense to turbocharge a smaller engine to output the same amount of power a larger displacement engine could produce. And it's not just about fuel economy either, but also has to do with track performance of these cars. A turbo charged 4 cylinder is going to be much lighter than that NA V8, and it will produce the same power. So unless you're trying to make a supercar, the lower displacement engines make a hell of a lot of sense.
Heavy_Gap_5047@reddit
I can see why people think this, but it really breaks down in real world applications.
OffRoadAdventures88@reddit
You’re looking at it completely wrong. Hp is a derived number, torque times rpm. Big engines make gobs of torque down low.
JoshJLMG@reddit
Big engines don't always correlate exactly with their torque. The 5.0 in the 2018 Mustang makes 420 lb-ft, while the 5.2 in the GT350 makes 429 lb-ft.
OffRoadAdventures88@reddit
Both of those are weird because they are designed to rev to the moon. The coyote past 7k and the predator even further. I had a 2012 gt for a bit and yes it’s still a v8 with low end torque but the peak torque was much higher than normal for an American v8. Makes sense since the coyote was heavily engineered by the German ford team.
JoshJLMG@reddit
Slight correction; Voodoo is in the 350, Predator is the supercharged one in the 500.
OffRoadAdventures88@reddit
Ah yup my bad.
03zx3@reddit
No, but it's a good indication of potential power.
Overdrv76@reddit
Plenty of replacements for displacement. Super charger, turbo, direct injection and NOS for a few.
danjet500@reddit
My 513 cid BBF makes 550 hp at 5800 rpm and 580 lb/ft of torque at 4100 rpm. It makes over 500 lb/ft from 2500 rpm on up. I love big ass engines.
JoshJLMG@reddit
Valvetrain makes a huge difference. Look at the Mustang VS Camaro (when you still could compare the two). 460 horsepower out of a 5.0 VS 455 horsepower out of a 6.2.
01WS6@reddit
Good comparison, lets look at them: 6.2L LS3 on the left, 5L Coyote on the right
Oh wait... the 6.2L LS3 is physically smaller and lighter than the Coyote while making the same power? Hmm i guess there isnt a replacement for displacement, only alternatives.
Displacement doesn't represent physical size or weight, which is what actually matters in the real world, and why comparison displacement to peak power is irrelevant.
No-Animator-3832@reddit
V8 geeks in here are killing me. The replacement is boost "but what if you boost the v8" no dummy, that's the replacement. You don't get the displacement AND the replacement.
coryeyey@reddit
I was honestly surprised by how many V8 fanboys showed up here. People trying to explain that you can get really impressive HP and torque numbers from things like superchargers and hybrids/EVs are getting downvoted to hell. It's fine if you love your V8, but this thread takes it to a whole new level. There are just too many examples of cars that break this 'rule'. Like a 3 cylinder 1.5L engine producing 300hp, or that the Porsche 918 spyder is one of Porsche's fastest vehicles, and yet it's a hybrid(Like a Prius! ew! /s).
Nekrophyle@reddit
I think it is a true statement, but when used to talk shit on what in the end are superior powerplants it is kind of a weird take.
Like blanket claiming your NA 5.0 is just a better motor than any 2.5-3 straight six regardless of what is feeding the beast is just silly.
Yes, twin turbos would be better, all other things equal, on a 5.0 vs a 3.0. But just because something is smaller and forcefed doesn't mean it won't eat you alive in practice.
Sea-Eggplant-5799@reddit
It’s true. The sound, size and beauty of a giant V8 is something to behold.
Alex-S-S@reddit
Technologically it hasn't been true in decades. Forced induction and precise electronically controlled fuel injection has meant that you can achieve a lot of power and torque from a small engine. With good maintenance it doesn't even make it less reliable. But people love their big engines and it's wrong to dump on someone's preference.
Emperor_of_All@reddit
This has never been true if ever true, power to weight is a replacement for displacement, look at motorcycles they weigh nothing and have low HP and small engines but they will kill a car any day of the week. Force induction is also a replacement for displacement.
Silas_PBJAM@reddit
sounds like ur comparing the chassis more than u are the actual engine lol.
a stock na 2.0 from factory today compared to a stock (idk extreme) na 7.3? 7.3 more power
now mod for mod, u r always getting more power from more displacement. "motorcycle blah blah blah". thats weight arguement. power for power? car engine > bike engine
bitzzwith2zs@reddit
Been proven wrong.
Compression and higher revs is a good replacement, forced induction is even better.
Outside_Reserve_2407@reddit
But what if you apply all that to a V8? Ferrari comes to mind . . .
TaylorSwiftScatPorn@reddit
...I jizzed in my pants
Silas_PBJAM@reddit
r/UsernameChecksOut
Heavy_Gap_5047@reddit
Can't combine high compression and forced induction and high revs have other serious downsides.
racerx255@reddit
Laughs in e85/methanol
Heavy_Gap_5047@reddit
e85/meth is a far less efficient fuel.
BigJ168@reddit
That it is a stupid argument. It is more about engine architecture and efficiency than displacement.
TechInTheCloud@reddit
It’s an emotional statement, not a scientific one. And there is nothing wrong with that at all. There is nothing quite like a big old V8, and that’s something that is going away, when it comes to new cars.
The alternative statement is “an engine is an air pump” and we know there are ways to increase the mass of air through a combustion engine than increasing the displacement.
I’m quite eclectic myself. I’ve owned and driven many different cars engineered with wildly different philosophies on “displacement”, they all have their charms.
tidyshark12@reddit
You can literally calculate the amount of displacement a turbo will replace. So, it's untrue.
However, I do love the way that they don't have any turbo lag.
JUICE_B0X_HERO@reddit
I can make a 350sbc have more hp than a stock 454 big block, just gotta spend the money. On the other hand a modded 350 is no where near a blown 454.
mike1097@reddit
Yes. Always can make more horsepower! Sky is the limit.
ReditTosser1@reddit
That applied when hot rodders actually had to build performance engines. Typically the only things to improve performance were increasing bore/stroke, camming, and doing head work.
Head work (port, polish, port matching, extrude honing, 3-angle valve job, under cutting stems) was labor intensive and very expensive. Adding a cam with high lift required some head work, intake and exhaust, and carb mods/replacement. Another expensive endeavor.
So, the cheapest thing you could do is bore the engine 0.060 over, if the block would handle it. Put in a slightly hotter cam, and a better carb/intake. It was still a $1,000 job but doing a full work up on some heads could cost $3,000+.
So, it’s not a statement all about performance, but one of ROI.
come_ere_duck@reddit
It is, of course, partially true. But as any car guy knows it's not the only factor. I mean GM used to make 7.0L V8s that put out like 130 hp. and we make 2L 4 cylinder cars now that make 180hp and thats just a family car. It is generally correct that a maxxed out 4 cylinder engine will be outperformed by a maxxed out V8. More space for fuel and air to burn etc. But Koenigsegg make a 3 cylinder Gemera that outputs 1,300hp and a V8 + EV hybrid Gemera that puts out 2,350hp.
USAF6F171@reddit
Like 'the customer is always right' or 'money is the root of all evil,' the complete quote is "The only replacement for cubic inches is rectangular dollars."
Total-Composer2261@reddit
Also, the complete quote is, "The love of money is the root of all evil."
STGItsMe@reddit
F1 power units would like a word.
2fast2nick@reddit
Haven't heard anyone say that in a long time
Top_Donkey_711@reddit
It was mostly true 50 years ago when I started driving. Now I see family SUVs running the 1/4 mile quicker than the 1969 383 4 speed Roadrunner I had then. Turbos, superchargers, nitrous and other technologies have rendered the phrase mostly obsolete. Big engines can still make big power but it's not the popular way anymore. I also had a 1975 500 cubic inch Eldorado that made less than 200 hp
Dull_Support_4919@reddit
well it depends. whats important to you? sound? torque delivery? top end power? revs? fuel economy? it really matters what youre after.
but generally yes. when comparing apples to apples there is no replacement for displacement. what i mean by this is if all variables (technologies) are the same the bigger engine will make more power than the smaller one. what do i mean.
take your 4g63t. a high revving 4 valve DOHC. VVT. boosted making like 22psi. in the evo 8 it made like 276hp. out of a 2 liter.
you know what else made similar power? the mustang of the time. actually it made less power at 260 hp out of a 4.6 liter V8. so clearly the smaller engine is better. in fact i remember back in the day people talking shit about these muscle cars cus the smaller engines were making the same or more level of power with less weight. titles like "v8 killer" flooding the web.
except that 4.6 modular was a 2-valve single jingle sad gasm with nonvariable cams (i believe they were introduced in the 3v) and the compression ratio of a wet noddle and no boost. yeah its not gonna make a lot of power. take the 4v DOHC v8 out of the cobra strap a snail and pump 20 pounds of boost through it and i guarantee it would make a HELL of a lot more power than that 4g63. apples to apples.
Rlchv70@reddit
EVs
blizzard7788@reddit
The answer is always boost.
Outside_Reserve_2407@reddit
But what if you boost the V8?
ryandenney347@reddit
I'm 500 wheel on a 302 Ford V8 with a $300 turbo. Boost makes everything better.
Smooth-Apartment-856@reddit
You boosted a big engine. That basically proves bigger is better. Can you even put enough boost on a stock Miata engine to make anywhere near that power level?
AutomobileEnjoyer@reddit
Stock Miata engine gets you about 300 decently reliably. But, the speed difference wouldn’t be much vs the 500 horse mustang just due to power to weight.
ryandenney347@reddit
A 302 is on the small end of V8s. There's 454, 460, 455, 502 and even 632 crate engines out there.
blizzard7788@reddit
Even better. I doubled the HP of my 2005 Mustang 4.6 V8 with an Edelbrock supercharger.
Ok-Letterhead4601@reddit
This is the way.
thedr777@reddit
Turbo.
dglsfrsr@reddit
No replacement for max current capability times voltage.
sharpescreek@reddit
If you are building a hot rod.
Talentless_Cooking@reddit
It's a flawed statement, but you can't tell old people that. I was shopping for a car for my girlfriends parents, two cars with two engine options, a 4 and a 6. I tried both and there was no difference, the extra weight of the engine didn't displace the minor amount of extra power, so it was no faster. It probably could tow, but they had a 1 ton, so they didn't need it for towing. He insisted on the bigger engine, so that's what I got for him.
l5555l@reddit
It's always true. Yeah you can turbo anything but a bigger engine with a turbo will always be more powerful than a small engine with turbo.
Purplegreenandred@reddit
My turbo 1.5 liter honda has 50 less horsepower than my 1997 k1500
Ultrase7en@reddit
HAW YEE BROTHER, NEED SOME GIDDYUP IN THEM WHEELS🇺🇲🇺🇲🇺🇲🇺🇲🇺🇲🇺🇲🇺🇲🇺🇲🇺🇲🇺🇲🇺🇲🇺🇲
TactualTransAm@reddit
It depends. Usually the people saying that are driving slow vehicles with large engines. But. Realistically and scientifically I have to agree with the statement. If you can burn more fuel and keep the efficiency then you will make more power. But again the people usually saying that are in old inefficient cars or trucks trying to be better then you. Modified cars on the street can surprise you with any setup if they get built right. But scientifically you can't make the same power with 2L of fuel that you can with 5L of fuel.
TCivan@reddit
Not quite the same as a vette or hellcat but…
My v8 2005 Toyota sequoia is worlds different than my 21’ v6 4Runner even though they somewhat similar numbers. The V8 makes 287hp 314lb of torque.
The v6 makes 276 and 278lb torque.
The V8 is muuuuuuch smoother. And the torque is down low, so it never really struggles on hills or on the highway.
The overall driving experience is so much better. But it’s thirsty…. Really thirsty. 13city 19 highway. 15mixed.
Blu_yello_husky@reddit
I say that often
LordKai121@reddit
Yes, but no, but actually kinda?
Fearless-Dog942@reddit
The real meaning of “no replacement for displacement” is duty cycle, in my opinion.
Larger engines that aren’t too powerful that are not stressed much generally can do hard work for way longer than a small engine that has lots of stress with lots of power (usually more power than the larger naturally aspirated engines).
A naturally aspirated 6+ liter push rod V8 can work hard for 20+ years before needing a rebuild. But a small turbocharged overhead cam 3.5 v6 cannot do hard work all day long for 20+ years without an engine rebuild like a big naturally aspirated engine can.
If smaller engines can have a long duty cycle, maybe even longer than large engines, you will see smaller turbocharged 5 liter inline 6 engines that can make more power than the current large heavy duty diesels in semi trucks, but because of duty cycle, semis are still rocking large diesel engines.
On normal daily driver cars, small engines are better. But if you are planning to do lots of hard work, you’re better off buying a vehicle with a naturally aspirated large gas engine or a larger turbocharged diesel engine, because larger engines will do the harder work all day long for much longer without a fuss.
So “no replacement for displacement” is still a very valid point to me, especially in towing and pulling things.
But on a sports car, smaller engines can often be better than larger naturally aspirated engines, because smaller turbo engines are lighter, usually produce more power than heavier large engines, and will also make the vehicle handle better.
Who doesn’t like the sound of a throaty big V8, but if you really want a “sports car” I think smaller engine configurations are objectively better for a sports car, because of handling, and power. But if someone values sound and simplicity, then maybe a big displacement n/a engine is the right one for them.
Heavy_Gap_5047@reddit
I very much agree with the duty cycle aspect, I think very similarly. It's most accurate to say that engine displacement should be matched to GCWR.
A great example that I ran into a lot in a previous career was comparing engine life between the 350 and 454 in Suburbans. A Suburban is a vehicle that is generally often similarly loaded just hauling it's own massive weight around, and nearly identical ones where produced with either the 350 or 454. In the versions with the 350 the engine would be just plain worn out by 200k miles, while the 454 versions would often double that, or need to be really abused to kill the engine.
That difference all comes down to the duty cycle of the engine. The 350 had to work much harder to move the vehicle around day to day. Spending more time at high throttle and high RPM to accomplish the same work that the 454 did at less throttle and RPM. I'd imagine that if there was a total revolutions counter on the engine that the 350 at 200k miles and 454 at 300k miles would have the same total number of revolutions.
This also played out in MPG, often the 454 would get better MPG numbers for the same reasons. Less time at periods of low efficiency like running high RPMs and running rich during WOT. I recall I built, installed and tuned a 540ci engine for a customers K2500 Suburban. After all was said and done that sucker while making monster power still got high to mid 20s for MPG because it never had to work hard for normal driving.
Smooth-Apartment-856@reddit
There are tradeoffs for high RPM and boost that you don’t have to deal with when going with displacement. Big engines make more power at lower speeds, launching better off the line. And the rods and crank are less stressed.
Let’s look at a couple of extreme examples. Toyota’s GR Corolla has a tiny little three banger with a turbo making 300 horsepower. I forgot the displacement, but it’s under 2 liters. Impressive…but…
Ford’s 7.3L Godzilla makes 430 horsepower, burns regular 87 octane gas, and will last until Jesus returns. The GR Corolla requires 91 octane or better.
Now, take that Godzilla, give it an intake swap, a hotter cam, and a tune, and you are making 600+ horsepower naturally aspirated. With more compression and the right parts, 800 horsepower naturally aspirated is possible. Can you turn the boost up on a GR Corolla and get that much power? Not on anything resembling pump gas. E85 or race gas would be required. Plus I’ve heard the turbo 3 starts having head gasket issues at 500 horsepower. Plus, how long will that turbo three hold together, compared to the Godzilla?
Now drop that Godzilla into a Competent chassis like a Factory Five Cobra or Daytona. That turbo 3 Toyota will be out of its league.
And we haven’t even gotten to the boosted Godzillas yet. Adding a blower will put your horsepower rating into the four digits on pump gas.
Can a small, high RPM motor make lots of horsepower? Sure. But all things being equal, it will always be chasing bigger motors.
The reason you see so many 2.0 turbo engines on the market today is because fuel economy standards are pushing automakers toward smaller engines, and they have figured out how to reliably wring 300 horsepower out of a 2.0 turbo. And that’s enough power for a fun, performance oriented street car.
Much more than 400 horsepower in a street driven car starts getting bat poopoo crazy in a hurry. Once you get into drag racing, where federal CAFE laws don’t apply, bigger engines still reign supreme…usually bigger engines turning at higher RPMs with a fat blower on top making power levels small street driven 3 and 4 cylinder engines can only dream of. And if you do build a 4 banger that can hang with a supercharged V8, odds are you are giving up a lot of reliability/ engine life to do it.
For your average commuter car, a big V8 no longer makes much sense. For those times you really need power, it makes sense to start with the biggest engine you can, and go from there.
Heavy_Gap_5047@reddit
Good stuff, I only take issue with one statement.
There's a lot to be said for the low rpm torque and efficiency of a NA V8 in a commuter and modern cylinder deactivation and variable cam timing have reduced the downsides.
Lightning_Of_Fate@reddit (OP)
Great answer.
I laughed.
BeeYehWoo@reddit
This is what so many ppl miss. Technology is allowing engines to churn out power never before imaginable. To see a 4 cyl engine reliably meet a 300 hp figure was unheard of several decades ago unless you had some temperamental track engine that didnt comply with emissions, had a high loopy idle, no accessories etc... We have street engines now in that territory.
The same technologies available to 2.0 4 cyls are easily applied to big displacement v8s lets say.
An engine is just an air pump. Bigger displacement engines are capable of cycling more air than smaller displacement engines - there is never going to be a sidestep around that rule. With more air, allows for more fuel to be burned and therefore more power.
TraditionalBidN2O4@reddit
I would argue that a lot of this depends on what you want to do with your modified car. Drag racing? Displacement to the Moon. Time attack? Smaller and lighter every single time. Endurance Racing? Id take a stock GR over any v8 any day.
Mental_Theory225@reddit
My thoughts are "HELL YA BROTHER!!" nothing like a good ol' reliable pushrod V8.
mechapoitier@reddit
That phrase has been replaced by the replacement for displacement.
There are turbocharged cars out there these days that make their torque peak at 1,300rpm, and with variable geometries and valve/cam phasing makes the former torque peak at 5,000rpm-wide plateau of area under the curve.
It’s not absolutely instant torque like a giant NA V8 but we’re talking a split second here.
Heavy_Gap_5047@reddit
True, and admittedly impressive tech. But it has it's downsides that in many ways negates it's utility. Specifically that it compromises efficiency and makes for a highly stressed engine with a short lifespan.
To make high power under boost at low RPM the compression ratio must be low and fuel mixture high.
Smooth-Apartment-856@reddit
Now, apply all that exact same technology to Ford’s modern DOHC Coyote, and you’ll have a similarly shaped torque curve, but at a much higher level.
mechapoitier@reddit
Depending on what boost it can withstand compared to another motor, yes.
There are bottom ends out there with significantly lower displacement that can be untouched until north of 1,000hp
Ill_Praline2805@reddit
https://www.sonnysracingengines.com/engines/street-engines/sar-940-1650-hp-5-3-bore-space-hemispherical-headed-pump-gas-engine
No replacement for displacement. BROOOOO
Ill_Praline2805@reddit
https://www.sonnysracingengines.com/engines/drag-racing-engines/sar-1005-2100-hp
No replacement for displacement. BROOOOO
saintmsent@reddit
It's both valid and not. You can get the same power from a much smaller engine no problem. But it will be much more high stress and probably have a shorter life than a big displacement NA engine
thethirdbob2@reddit
Of course an engine with forced induction or even superior flowing cylinder heads has an advantage. But all things being equal, displacement overcomes. A larger engine can do the work at lower speeds with less strain.
TastyWrongdoer6701@reddit
No deterrent for current.
perception016@reddit
Of course. The more air and fuel you get through the engine, the more power you can make. All other things being equal, a 6L engine will make more power than a 3L engine.
You can use forced induction to shove more air into the small engine, but the same is true of the larger engine.
63crabby@reddit
Isn’t displacement the cheapest and easiest way to maximize horsepower?
Heavy_Gap_5047@reddit
Useable HP yes. but not peak HP for stats.
ryandenney347@reddit
No, add boost. The replacement for displacement is boost.
Complex_Solutions_20@reddit
Depends - are we talking peak power or across the board?
ryandenney347@reddit
Both. Average power under the curve. In my case I'm at full boost by 2500 rpm and pull to 6k. 550 lb-ft from 2500 to 6k.
6inarowmakesitgo@reddit
You’re smoking rubber at that point, depending on how heavy the vehicle is and its properly set up suspension and choice of tires.
Sounds like a good damn time though!
Elk_Man@reddit
Nah, boost is a supplement to displacement.
Key-Ad-1873@reddit
I think it's still true, always has been and always will be. The argument against it has always been that you can add a turbo to a small 4 cyl engine to make similar power to a bigger NA 8 cyl engine.
Yeah you can make 5-600 hp with that little 2 liter 4-cylinder when you swap the turbo, change out a bunch on tougher internal parts, etc. but I can do that with a Chevy LS and a cam swap for cheaper, and it's still got room to grow cuz I haven't even touched most of the inside or introduced forced induction
If you don't touch a motor, sure the phrase is defunct, but if you do the same mods to different engines, the bigger engine will almost always come out on top.
Bigger engine, bigger bang, more go go
Gwolfski@reddit
Regulation in terms of emissions (as well as fuel costs) killed off the era of the classic "American V8". It is the era of compression and forced induction now.
Heavy_Gap_5047@reddit
It's not really emissions regs, a V8 can be very clean, in fact they're easier to make run clean than a turbo 4. It's CAFE regulations, they are harder to force to get really high MPG in testing. The V8 will often get better MPG in real driving, but not in an EPA test.
IhateBiden_now@reddit
"a variant of this saying for EV motors"
Like calling the Porsche Taycan a turbo?
Gwolfski@reddit
I meant a variation of the "displacement" saying, as bigger electric motors get more power, same as making the engine bigger
invariantspeed@reddit
Work for work. No exceptions. ^((I’m almost ashamed at how nerdy that is 😅))
largos7289@reddit
Yea heard that all the time. Here's the thing on the street yes very valid, you can get just as much horse out of a 4 banger that you could out of a V8 on the streets stockish. I say stockish because forced induction could be considered a modification. That 4 banger is gonna need some heavy modification to get those numbers down. It does have the weight going for it. However once you start doing the same thing to the V8, it's gonna make a ton more horse then the 4 banger. So all things being equal as in forced induction to forced induction there is NO replacement for displacement.
coryeyey@reddit
I get what you're saying. The problem I have with this sentiment is that this isn't how cars are made. Companies aren't trying to pump out as much HP as humanly possible. For example, maybe they are looking to making a hot hatchback. They aren't going to want a supercharged V8 producing 700hp. They could either go with a NA V8 producing 300hp or a turbocharged 4 cylinder making 300hp. So in reality, there is a replacement for displacement. The only time there isn't is when you are trying to push out ridiculous HP numbers for supercars that almost nobody drives.
avoidhugeships@reddit
A modern NA V8 is going to be putting out closer to 500 HP than 300hp.
TeacoreLeather@reddit
Still valid, yes. But it depends on what context you're putting it into.
For speed and Motorsports? No. The formula is no longer big, heavy, high HP motor.
For torque, Americana nostalgia, and the aural experience? Absolutely valid. Nothing sounds better than an American V8. Don't care what anybody says about V10's or 12's or what 4cyl Honda or VW Golf they've got. It doesn't get any better than a good old V8.
stevrock@reddit
Usually said by some twat who peaked in high school when he was rocking a 140hp v8
Heavy_Gap_5047@reddit
Absolutely, it's just a fact of internal combustion engines.
clipples18@reddit
Yes there is. It's called forced induction
tankinbeans@reddit
Having never owned, and having only briefly driven a V8, I've never really had a dog in the fight.
I've had a number of turbocharged 4 cylinder vehicles (including a Focus ST, Mazda3 and 2 CX-5s), NA 4 cylinders, and NA 6 cylinders (2 of which were GM 3800s). I've thought they were all interesting in their way.
I don't have the subjective capabilities to say one is "better" than another, but I'm impressed that my 3500# CX-5 turbo achieves better fuel mileage than my 95 Escort did. I guess because I've been relatively spoiled by well-done 4 cylinder engines, I can't get hung up.
RunninOnMT@reddit
It depends on what you're trying to replace.
Power? Oh there's absolutely MULTIPLE replacements for displacement in that case. Feel? Ehhh not so much.
dpresme@reddit
A little does a little good, a lot will do a lot of good.
Impressive-Purple206@reddit
For a simple no frills vehicle that's easy to drive in all conditions?
It holds very true.
Modern engines might make more power from less displacement, but it's at the expense of low end torque and driveability. This is a part of the reason modern engines need to be mated to 8-9-10 speed autos, to make up for the narrower powerbands.
Proof_Bathroom_3902@reddit
Chevy LS 4.8 with twin Wuhan war whistles begs to differ
allawd@reddit
More or less yes when keeping all things equal. It's just thermodynamics.
As an example, modern turbo 3.0 is pretty much always going to beat a modern turbo 2.0 with the same level of boost and technology. Comparing a outdated NA V8 to a current I3 or I4 isn't really a fair comparison and just serves to justify an incorrect belief.
hellhastobefull@reddit
Reliability, adding in more parts adds a in more points of failure. Old Chevys ran forever because they were simple.
Brainfewd@reddit
Hasn’t been relevant for a while IMO.
Coming from someone who loves a snotty big block (or small block) and even rides a Harley.
Left_Net1841@reddit
That it’s no longer true.
That said we have a 94 Impala SS in the garage and my Yukon XL has an 8.1 Vor-tick under the hood. 14L between both….thats 7 of my Impreza lol.
I am under no illusions that those 2 are fast by any measure and an endless list of 4cyl cars could blow the doors off both.
rustystach@reddit
Makes you sound old and stupid.
CraziFuzzy@reddit
Boomers can't deal with change and/or innovation.
Bb42766@reddit
It's a absolute FACT There's no replacement. N/A or Boosted Anybody that thinks any different? Absolutely doesn't know what thier talking about.
Docod58@reddit
Forced induction the only subsitute.
Bombaysbreakfastclub@reddit
Yes and no.
For anything measurable, no, no longer valid, and to an extent you could argue never did. In reality it did because of cost.
For feel, nothing replaces it (in my opinion)
Sarionum@reddit
The replacement is turbos. And if that doesn't work add a supercharger on top. And if that doesn't work make the whole system a hybrid. Huh, kinda sounding like a real car on the road...
smthngeneric@reddit
I mean it's true to an extent. It's not as literal anymore with forced induction being so easy and popular but eventually you're maxing out your turbo, revving it more than the engine can support, and have more compression than the pistons can handle, and then the only thing you can really do to make more power is add displacement. But the days of bigger engine = more power were killed in the 70s with the gas crisis and emissions.
walkawaysux@reddit
It’s definitely easier with a big engine. You can do it with the smaller ones but all the boosting makes it fragile