art911

I am considering fitting a Vitesse stg3 kit with 72# injectrors, and piggyback.
Ive read many posts about this kit, and also know from johns site that it would make about 320 rwhp at 15 psi. The MAF and turbo are capable for more power though. My question is what is needed for that more ? 3" exhaust ?

What other things should one add to go to a reliable 400rwhp and at what boost pressure ? I guess thats why John advises to go with #72 injectors instead of 55.

Jeremy Himsel

To make more power you'll need either more boost, more RPM's, more displacement, more octane, or more efficency. Meaning headwork, cam, headers, etc. The Stage 3 can put up some serious numbers in 2.5. but it's not as easy as simply just turning up the boost. Well, not for very long at least.

stv951

I was expecting this thread to have more responses...
I believe that the maf can handle more power accurately and reliably

ehall

It can and has...but not on a stock 2.5 @ 15psi. You ans the original poster should do a search under the name "Special Tool". He made the most power that we know of. He used VERY high octane fuel,(of his own design) a big valve head, from Vitesse, SFR headers, special cam, Vitesse wasted spark, 3" exhaust, and some other stuff. He also happens to be an excellent tuner, and has monitoring equipment for everything from A/F ratio to multiple EGT probes. He made his runs at approximately 23 psi.
Jeremy's post, above yours, was right on the money.

Tom M'Guinn

I trust you have seen this?

http://www.vitesseracing.com/html/stage_iii.html

IPSC

I have a Vitesse stage 3 kit and I have yet to add the piggy back. My goals are exactly what you asking. Out of the box AND... with a leaky Throttle Body ( I just got a rebuild kit) I am making 300 to the wheels.

I have acquired an extra head to get worked over, i.e. port polish O ring.

I have acquired a SFR intake and a phenolic spacer kit.

I am looking into a new Cam.

I am saving for a set of SFR stage 2 headers (yes I know there was just a HELL of a sale on them).

I already have a 3 inch exhaust and I am debating on the 3 inch down pipe.

I am hoping for a reliable 375 to wheels at 18 PSI.

IPSC

stv951

thats more like it ...
I have just bought a Vitesse stg 3 too, but havn't installed it yet

How did you find about the leaky throtlle body ?
Any issues with the 3" downpipe ?

stv951

bump

Dr. Dynamics

I could add that with juanchovidals car we didn't go more than 325 with stabilized boost curve. But I can really say that John's cam really was more fun. The car kept screaming that I wanted to rotate the tach to see were the needle was going
Never did dyno it with the cam afterwards.
If you dont want to go that route and get to the 300s faster with less $$ i would recommend one of tims turbos @ SFR. My torque felt better for daily driving with less psi than juanchos car with more than 22K goodies.
His car really screamed though

gt37vgt

Yeh a kit should be more comprehensive and cost effective than a mix and match approach. If one was to open a thread for "how to spend 4K" it would go on for ages . but reaaly one should be able to get Turbo full exhaust and plug in programmable efi and injectors for that kind of coin And then be considering cams inter coolers TB.
Seems that 350rwhp is a more realistic expectation for a reliable 2.5 with no more than turbo and tuning done .
It would seem the only way is a bit laggy .
If you have a reliable 350+whp car with nothing more than turbo exhuast EFI
speak up we are all interested

gt37vgt

gee a just craped there the answer to your question is for how much power is ........"HEAPS"
and what other mods EXHAUST IC CAM TB INLET MANIFOLD . in that order