Was hoping to save and rebuild this uncommon turbo… guess not :(

Posted by CanoegunGoeff@reddit | projectcar | View on Reddit | 13 comments

I’ve got a JDM CT20B that I was planning on rebuilding with some upgraded internals, but found three somewhat deep cracks in the exhaust housing. They aren’t near any mating surfaces, bolt holes, or near the turbine itself, but I know they’re going to keep progressing over time and eventually lead to a leak at best or a rapid unscheduled disassembly at worst. Don’t know that I should trust it for the project I have in mind. Can’t just buy another housing. They’re just not out there. I can find only a few similar examples of full turbos for sale, but after shipping, I may as well just buy an already rebuilt one, which won’t have the exact internals I wanted to use, but will still be a direct fit for my application. Was really excited to both save some money and build something fully custom. Oh well. Such is the project car way, I suppose. Always some hiccups.

Reply to Post

13 Comments

[-]

Fender0122@reddit

I’ve pulled apart a few k03/k04’s and they’ve pretty much all has cracks like that and worked just fine. I even threw a tiny bit of exhaust paste in one and was surprised it didn’t just burn away. I’d send it. If you rebuild it yourself, be sure to get it balanced somewhere (I’ve heard diesel shops might). Snapped an exhaust turbine off and my guess was bc I didn’t perfectly line everything back up

[-]

CanoegunGoeff@reddit (OP)

I asked a friend too who is knowledgeable about boosting cars with spare parts, he also said I can probably just send it. He’s in another state though so I can’t have him look at it in person. I’m gonna take it to the guy I bought it from next weekend for him to take a look, he has experience rebuilding a lot of turbos, and I want his opinion too. He knows where to go locally to get new internals balanced as well. I figure if I was sticking to the stock 10 psi of boost, it wouldn’t even be a question, but I was planning on taking this turbo almost all the way to it’s maximum boost efficiency of 18 pounds. That’s the main reason the cracks concern me. I’m new to turbos, so just trying to get multiple opinions I suppose.

[-]

Fender0122@reddit

Mine were running at 20psi, so you should be fine 😉

[-]

CanoegunGoeff@reddit (OP)

I just had my buddy look at it last night, and he told it me should be okay. He looked at the internals I pulled out of it and was impressed with those as well. Very little to no wear in the bearings, no scoring, no obvious heat damage or anything. I think I will move forward with cleaning up this turbo and rebuilding it with upgraded internals as I planned. I reckon I’ll start with roughly stock boost and take it up incrementally and see how it does.

[-]

Confident_Guide_3866@reddit

Pretty sure I have one of those sitting in my attic

[-]

CanoegunGoeff@reddit (OP)

Do you have any plans for it? What kind of shape is it in?

[-]

Confident_Guide_3866@reddit

Dang just checked and it’s a ct15

[-]

Divisible_by_0@reddit

If you haven't seen[this yet](https://upgarageusa.com/products/turbo?srsltid=AfmBOoq66QRUL_LfRCBtupBLlgRIlDLRRaiQTtf6Pz-9qN4cVTstphie)

[-]

CanoegunGoeff@reddit (OP)

I did see that, but after what I’d expect after shipping and tax, I may as well just buy one of the rebuilt/upgraded Kinugawa units. The turbo I’ve already got was included with a complete engine I bought from a buddy for only $1,000, and I was hoping to clean it up, rebuild it, and upgrade the internals, something like less than $400 worth of parts plus whatever it would cost to get it balanced. That was going to be the real value of using the one I’ve already got. So now, it seems to be a question of spending nearly $1,000 for another used turbo that may be in similar shape that will still need the internals upgrades? Or do I spend a little over $1,000 and just buy one that is already done? I ain’t trying to be frugal- I’ll be spending roughly the same amount of money on just the turbo either way at this point, just trying to decide now which route would be my best bang for buck. I searched online literally for hours trying to find every CT20B option I could find, and it’s pretty slim. I just already have the manifold and downpipe and stuff for this turbo, and so I’d hate to go with something completely different that’ll require total custom fab work instead of using the stuff that came with the complete donor engine I already have. That’s why I’m dead set on the CT20B even though it’s making my life more complicated rn lol

[-]

Siege9929@reddit

Have it welded and machined.

[-]

CanoegunGoeff@reddit (OP)

I’ll have to do some networking to find someone who can weld cast iron, and in such a tight space too. I know cast iron can be a toughie.

[-]

IGOR_ULANOV_55_BEST@reddit

You will spend more money getting that housing welded and machined than you would on a new turbo.

[-]

CanoegunGoeff@reddit (OP)

Yeah, that’s about what I expect. It’s looking like I should just buy an already rebuilt version, since those are available. I’m just really bummed about this one not panning out the way I’d hoped.