R.P.M.

iTrader: (3)

I just bought a brand new TO4B turbo, that was off of some sort of deisel application.
It has a Switzer TO4B compressor side (not sure of any other specs) and a 1.32 A/R exhaust housing with a 2.54" P-trim turbine wheel.

Now I have talked to a few turbo shops and they told me I can change the exhaust housing no problem....same with the compressor wheel/housing (because it's waaaay too small for what I want).

My plan is to run this on a half bridged 13B...so I'm wondering what i should choose for and exhaust housing?

1.15 A/R ? 1.00 A/R ?

And what I should choose for a compressor side...the turbo shop told me I can interchange it with anything made by Tubonetics right up to a T88!!
A freind of mine who deals with alot of turbo stuff, said I should try and get a T72. The deisel shop told me to go with a 60-1...... neither of them no anything about rotaries.

My goal would be around 400-450 whp...can it be acheived with the turbo core that i have?

2a+RoN

if your looking for 400-450, i think you should listen to the turbo shop about the 60-1, great wheel, and proven to work great on rotaries. I would almost leave the 1.32 a/r on there with that half bridge and give the engine some extra room to breathe. You could go with a larger wheel, but a t72 is quite large and might be more than what you're looking for.

sleeperfc

bdc has said time and time again with the half bridge you can run a fatty turbo and spoot it lower.. it will spool a 60-1 too fast and run out of breath up top.. alot like the stocker.

he had made big power at not so high boost levels with a t70. 1.15 rear is the hot side size he says to run. There is some guy on here running a 1.32 rear and he calimed it boosted just a tad later.

is the hot side devided or not? devided makes it spool a little faster. get the comp and all up to a t70 or t66... something thats gonna make power up top. the half bridge moves the power band of a big turbo down in the rpm range. if i remember right someone did mid 400s on a half bridge and the master power t70 at 14psi.

bdc seems to be a really nice guy, ask him about setups if your going half bridge. thats his area.

R.P.M.

iTrader: (3)

Yes the 1.32 housing is a T4 divided. What if I just upgraded the compressor to a 60-1 and left the turbine alone?

sleeperfc

you have a half bridge or plan to later?

that makes all the difference.

if you have the bridge already then the 60-1 will be kinda too small and power will fall off up top. go with a t70 or t66 or 62-1.. something with some beef to it.

if you dont have the port yet then the 60-1 will be fine but the 1.32 rear will be WAY too big. wont spool till 3rd gear pulls.

dag

So you're asking wether or not you should change the housings or the housings and wheels? If it's the latter then it seems an awful waste, just buy the proper turbo.

R.P.M.

iTrader: (3)

Yeah I know...it does seem like a waste...

I dont have the motor built yet...this is an on going project that will likely take me until next summer to complete. As of right now I am gathering and collecting parts.

The motor setup that I will be using is a half-bridged Cosmo RE with T2 housings and S5 T2 rotors.

I am leaning towards a 1.15 P-trim with a T70 compressor and housing.

sleeperfc

that motor with that turbo should make 450ish rwhp at like 15psi. race gas and more boost and you will need bullet proof everything to handle the power.

R.P.M.

iTrader: (3)

So what kind of stuff would I need to bullet proof to make any more power?

sleeperfc

time to read up... cooling system should be upgraded, oil pressure upgrade to 80psi spring, water/meth injection, (www.coolingmist.com) super beast clutch, vented hood, ported/modded TB, engine brace.. the list goes on and on... i have read the stock drive train is good to 400hp or so. things might start to break.

dunno if you have a s4 block or s5 but the s4 block has a seak spot in the rear plate that likes to crack and leak oil like crazy and you will have to take the motor apart to fix it. seen it happen to a local guy.

just get to reading man
there is lots of info on here.

hit up bdc and ask him about setups. get him to port the motor too.

R.P.M.

iTrader: (3)

I am buying an OS Giken 12lbs flywheel and twin disc clutch off a buddy of mine and as I mentioned before I will be using Cosmo RE irons with T2 housings and S5 rotors.....I think that should be bullet proof enough .......well it's a start anyways. But yeah I see what you are saying.