patman

iTrader: (3)

I know this is asked all the time, but every time i try to figure it out, i just get more info that doesnt relate to the old info. anyway, heres my question:

I am running a ported (~30% bigger ports) s4 TII motor with S4 NA rotors(9.4:1).
Right now i have the stock turbo @8psi. Problem is, my power curve flattens out at about 5500 rpms, which is a bad place ot flatten out. I think this is due to the turbo not flowing enough for my engine..although i could be wrong.

so, what turbo should i get if I want a very strong power curve all the way thru. My max boost level will be about 12 psi, but i want a turbo that could support at least 15 just for redundancy. i also want the smallest turbo that will do what i need, because at this boost level, i dont want a lot of lag. I will be running this with a FMIC and using my microtech as a boost controller if that makes any difference.

Ive been looking at T04E and T04S on ebay....is this about right? .60 A/R compressor, 1.0 A/R hotside is my best guess so far as to what i want.

anybody got any good ideas?

thanks
pat

XSTransAm

I wouldent buy an ebay turbo

www.agpturbo.com

patman

iTrader: (3)

hey mike... i was gonna ask you anyway..

didnt say i was gonna buy one ..just lookin. mostly i just need to figure out a size estimate...

hey btw i got a idea about ur car...probably a dumb one but what the hell...shoot me a im..

pat

Infini IV

Here are a few Garrett/Turbonetics turbo's that will net you about 300rwhp at between 12-15psi boost with quick spool:

T04B: V-trim, Super V-trim, H-trim, Super H-trim
T04E: 57-trim, 60-trim

Assuming you were to use the cheap and plentiful HKS cast manifold... to make your desired full boost between 12-15psi at 3000-3500rpm, you should use these housings with a P-trim turbine wheel:

T4 Tangential/undivided: .81 or .96

Any of the above combo's should get you to your goals and should continue your power curve up near redline.

patman

iTrader: (3)

actually, im planning to make my own mani out of prefab mandrel bends, but that shouldnt make much difference.

thanks for the info

pat

Infini IV

Although I have no personal experience, I've read that you could be surprised at how much of a difference a good, equal length and fully divided manifold would make in spool-up time. If you're making your own fully-divided manifold, go with a:

T4 Tangential/divided: .84 or 1.00 A/R housing

patman

iTrader: (3)

ok thanks. mine will be fully divided and equal length also, and im a pretty good welder, so it oughtta be decent quality.

i may still wimp out and buy a hks one...depends if ive got the money when i get the rest of my kit put together.

pat