turbo option for my ca18det

[forty7wombat]

hey
i have a ca18det (s13) that needs another turbo upgrade, it currently has a standard rb25det turbo. I could either high flow this turbo or get a s15 ball bearing or a t3/t4.
what would be the best turbo? i understand i may have to change some flanges.

the engine's running:
upgraded maf
450cc injectors
acl big and bottom end bearings
external wastegate
front mount intercooler
aftermarket chipped ecu

thanks

[cotbu]

Why do you need to upgrade? Do you mean you want to upgrade? What is this cars purpose? Are you looking for maximum performance? Can you tell me what crank and rod bearing have to do with turbo selection? What maf did you upgrade too? These are all rhetorical questions!

[Croustibat]

Nearly no S15 had bb turbos, only the early S15 spec R in Japan did.

If memory serves, the standard rb25 turbo has a ceramic wheel, which shatter when going >15psi, so i would not use that. I dont know what you call "high flow" a turbo, and i am quite sure i dont want to know either. It sounds more like ricer trick than real work.

Anyway S15 bb turbo is called a gt2560r. It works great, is nearly bolton, although your injectors might be a bit small. T3/T4 are outdated turbos and what you will not spend on the turbo itself will be spent on custom work for manifold, elbow, downpipe. They are too big for these engines too.

What is your MAF? An SR20det maf is ok for that setup. Nearly maxed but ok. You will need a real tune though (and maybe a fuel pump in the near future if you are still using the oem one)

I am currently running that kind of setup and it feels quite nice and responsive. It is making over 300HP but i am running e85 and my own tune, that helps a lot. On the other hand, friend of mine is currently installing a gtx3582r on his CA ... so it really depends on your objectives (and budget).

[aintnobiscuit]

Croustibat is right and wrong in regards to t3/t4 turbos.

Right: They are outdated tech. Does this make them bad? No, this just makes them not as good as a gtx30 or a borg warner EFR series turbo. For example: some people still use windows. Does that make windows bad? no.

Wrong: A t3 is too big for a ca18det. I personally am running a ca with a t3 50 trim .48ar and there is almost no lag. The biggest thing you need to be concerned with on a smaller displacement motor is going to be the rear housing.

Buying a legit garrett t3 turbo is not a bad idea, buying a godpseed POS is a bad idea.

Here's a video of when i had an exhaust leak and was only running 15psi. It's on a rough tune done in my garage as well. Later i tuned it on a dyno and its quite fast. I'm actually going to up the compressor and put a stage III wheel in so i can get into a better part of the efficiency. Should be putting down 400 pretty soon here, and that's only because i don't want any lag and have a hard time hooking up in a < 200lb car.

Fly by 1st through 3rd - YouTube (http://www.youtube.com/watch?v=PC98uZP8edk&t=9s)

Bottom line is learn to read compressor maps from here [http://turbobygarrett.com/turbobygarrett/turbo_tech_expert] and find a turbo that suits your goals. People on zilvia are bitter at people who prefer or have a CA18 for some reason. You might want to check out nicoclub instead if you have a CA, they have helpful people and a lot of knowledge.

[Croustibat]

Bottom line is "there are proven receipe for cheap power on a CA18DET, follow them".

the gt2560r is one of them. The T3/T4 are not. Not that they perform that badly, but they perform worse and what you wont spend on the turbo will be spent on custom mani / flanges / elbow / downpipe /wastegate / intercooler piping. In the end, why bother spending money adapting something that wont be better ?

Considering you can get a secondhand gt2560r for 400$ (got mine for 300£ shipped) and rom tunes exists for it (with 550 RB26det injectors and Z32 maf), i would not bother going T3/T4.

[Izento]

T3/T4 has already been proven to work on CA's and there is no such thing as performing "worse", only different spool. It all depends on your purpose for the car, whether it be drag/drift/autoX. That is the most important deciding factor in choosing what size turbo to go with.

[aintnobiscuit]

Yeah, it really depends on your goals. I have a fully built CA with a haltech and don't run a MAF, so none of that stuff really applies any more. Build to how you want to drive it.