MGB / MX-5 Body Swap
Posted by _Modern_Caveman_@reddit | projectcar | View on Reddit | 54 comments
The MGB/MX-5 body swap series starts here — classic British body, Miata chassis, and a lot of damage to undo first. I'm trying to document the process with some videos. If anybody here is interested in this project - I'll leave a link to the video in the comments. Cheers !
motocycledog@reddit
But without the suss mechanics what the point of an mgb?
Vast_Builder1670@reddit
Is it really an MG without Lucas electrical issues and having to fiddle with the SUs every few outings?
forgetsalot@reddit
I put a pair of su’s on my old 510. Lasted 2 weeks till I put the weber side draft back on
Vast_Builder1670@reddit
I just re built my SUs. Turned up right now. We will see how long it lasts. I am eyeing the vmaxscart supercharger and efi kit
404-skill_not_found@reddit
What are “SUs”?
majortentpole@reddit
Carburetors
_Modern_Caveman_@reddit (OP)
Why SUs ? What does it stand for ?
ARottenPear@reddit
Skinners Union
Fearlessleader85@reddit
They came with twin SUs up until the second half of 1974, then they got an even WORSE carb: the Zenith-Stromberg. The ZS carb was generally a piece of dogshit, but what made it especially bad was the automatic choke had a place that really liked to develop a leak and drip gas... directly onto the catalytic converter heat shield right below it.
The SUs were great compared to that piece of shit.
But my MGB is now EFI and turbo, because SUs and Lucas parts suck.
Vast_Builder1670@reddit
What EFI kit did you use? I would love to swap my Sprite over to EFI.
Fearlessleader85@reddit
Haha, no kit. I made adapter plates by carving them out of plastic casting them into aluminum from melted beer cans. Then i used the throttle bodies, injectors, and fuel rail from an Arctic Cat XF800 snowmobile, because it was the cheapest stuff i could find that could support 200+hp.
Then i welded a 36-2 trigger wheel onto the crank pulley and mounted up and NB miata crank sensor i had laying around. Then i ground a tooth off the Pertronics distributor that came with the car and used it as a cam signal.
I've got the Igniter and coils from my NA6 Miata that i pulled out when i switched to COP running wasted spark ignition.
The Siamese Port is generally problematic when tuning with batch injection, so i run sequential with 4 channels running only 2 injectors, so it squirts in an ABBA pattern.
It actually ran really well until all the crap in the gas tank kept clogging up stuff, so I'm replacing the gas tank with a fuel cell. Just haven't done it yet.
The turbo is from a Mazdaspeed3 and i got it on FB market for $25.
ARottenPear@reddit
Oh ok, so just easy stuff then.
Fearlessleader85@reddit
Ha, yeah, no sweat.
Just the turbo manifold took me like 40 hours to make. But it's a Lemons build, so time doesn't go towards budget, just parts and materials.
ARottenPear@reddit
Believe it or not, the Zenith-Stromberg in my '76 has been rock solid for the 20 years I've owned it. The SUs in my 1970 GT have given me tons of trouble. I know that's not the normal experience.
_Modern_Caveman_@reddit (OP)
I know the paint. This is why I work only with Japanese carbs. Webbers are good too though.
Fearlessleader85@reddit
I will stick with my speeduinos and EFI.
_Modern_Caveman_@reddit (OP)
Ooohhh... Thank you for the explenation. I didnt dissasemle the MG myself, didnt have tese in my hands...
404-skill_not_found@reddit
Thanks! Dang, the comments that followed were particularly illuminating.
volpin@reddit
Carburetors
Yubitzume@reddit
But SU tinkering, is why you own an MG or Triumph😁
Nicename19@reddit
I thought triumphs commonly used Strombergs, similar carb but uses a diaphragm
Yubitzume@reddit
My spifires and gt6 had SUs I think later US models used Strombergs not sure if it was the same model as on heralds
poorboychevelle@reddit
Did you know Lucas invented the intermittent wipers?
And also the intermittent headlights, intermittent starter, intermittent radio....
Diogenes256@reddit
Let’s go out in the MG. Will it start? Dunno, depends, did it rain last night?
_Modern_Caveman_@reddit (OP)
Oh, he meant carbs, not suspension... well, tottaly agree but I balance this absurd oversight and stay faightful to the only true and proper solution on my other projects: https://youtu.be/CqEUWx0Z1R0?is=9rR2G_VkQG88-OyB
_Modern_Caveman_@reddit (OP)
:D
_Modern_Caveman_@reddit (OP)
ehm... to have moded MX5 suss with MGB body ?
_Modern_Caveman_@reddit (OP)
video: https://www.youtube.com/watch?v=de4C3UVXspU
rational_overthinker@reddit
sweeeeet!
HulkSmash-1967@reddit
Following want to do this with a sunbeam alpine
JackTheBehemothKillr@reddit
Personally, I strongly recommend you swap the suspension subframes and drivetrain. A hat car is extremely difficult to pull off properly
jankenpoo@reddit
There’s so much room in an Alpine! I think it would be easier than a B, but they still make everything for a B
_Modern_Caveman_@reddit (OP)
When do you start ? One advice - end any relationships before, no point of making a mess, you won't have time for those. Buy a hammock, bring a fridge to your workshop. Aaaand that's about it.
VampyreLust@reddit
I was like the MGBGT's, how close are they to be dimensions of a MX five?
_Modern_Caveman_@reddit (OP)
20mm wheelbase difference.
Maumau93@reddit
This says less than 5?
_Modern_Caveman_@reddit (OP)
It's MX5 NC buddy. Wrong car you got there.
Maumau93@reddit
Just watched your video. Cool project. I'll be waiting for the next one
_Modern_Caveman_@reddit (OP)
And I'll be pushing to deliver. thanks.
sideways_86@reddit
MGB appears to be almost 5cm longer wheel base (when compared to an nb) https://www.carsized.com/en/cars/compare/mazda-mx-5-2000-roadster-vs-mg-mgb-1973-coupe/
_Modern_Caveman_@reddit (OP)
Nah, its 20mm. 5cm is total length.
kon69nor@reddit
POLSKA GUROM! subbed.
ShaggysGTI@reddit
NC engine and top loader 6 speed?
_Modern_Caveman_@reddit (OP)
Yes sir.
ShaggysGTI@reddit
Noice! You know, supercharger is best charger…
_Modern_Caveman_@reddit (OP)
And the most expensive charger...
ShaggysGTI@reddit
It’s like a divorce… they’re expensive because they’re worth it.
Malarky3113@reddit
Best Damn Shop Around on YouTube is swapping everything from a Miata into a Ford Courier. Almost finished with the project too.
CromulentPoint@reddit
I’m interested to know how you deal with the +/-25cm difference in track width. Fender flares?
_Modern_Caveman_@reddit (OP)
All coming up in next videos, Patience. Not everything is figured out yet, but this one we figured out. I'll post here to let you know when next video is up. Every second week for now - so next is Friday 08.05.
RunninOnMT@reddit
I believe they call this a “hat car” in the 24 hours of lemons. Sweet!
resolve_it@reddit
Mgb convertible would have suited better imo
Eragaurd@reddit
Subscribed!
_Modern_Caveman_@reddit (OP)
Thank you !