how much boost will i need

rob10s2 · Jan 15, 2009

this summer i plan to get some trick flow heads put on my car (s trim 94 gt 5spd) as well as a trick flow cam (i think the car already has an aftermarket cam, but i have no way to confirm this.) right now i see about 6 pounds of boost at redline. with 3.55 or 3.73 gears, drag radials, tfs intake mani, and tfs twisted wedge heads, how much boost will i need to run low 12's-high 11's? what size pully will this be? also will the ablity to run these times require more power than the stock block can handle? and if you have an opinion on the 3.55 vs 3.73 debate, feel free to weigh in :thumbsup:

El_Diablo · Jan 15, 2009

boost is just a measure of restriction.... the size pulley you need to run a certain amount of pressure is all up to your setup

just because you have drag radials doesn't mean you will hook up either

stang94X · Jan 16, 2009

just run what you have now and see where youre at, if you want more afterwards then get a smaller pulley

Lebedin8654 · Jan 16, 2009

my car is right in the high 11 to low 12 sec. area and i am seeing 8 to 10 pounds of boost, thats on a S-trim with Cobra intake and GT40 heads.! But if your running a stock motor than your 8 to 10 pounds wont touch mine cause you dealing with a lot of back pressure and not making a much power per pound as me, thats just my thoughts!!!

LAFENATU · Jan 16, 2009

Im still trying to figure out why your only seeing 6 pounds with an s-trim.

You should be seeing more like 10 with a 3.33 pulley.

Do you run a power pipe as well?

rob10s2 · Jan 16, 2009

n power pipe, however i have the trick flow intake manifold and full exhaust. also i think i have a small vacuum leak in the back of my intake manifld gasket. i thought these kits only made 8 psi out of the box?

novi281gt · Jan 16, 2009

just boost it till it blows hahahahah jk

El_Diablo · Jan 16, 2009

they make 6-8psi on stock cars, you could have an incorrectly installed bypass valve...

rob10s2 · Jan 16, 2009

well vortech used to make a 5-6 psi kit with an s trim, i think i have that one, i bought the car with the blower on it. but i could have the 6-8 one and be seeing 6 b/c of the full exhaust and tfs intake manifold. but back to the question, will 10 lbs get me where i want to be? anyone know this pulley size?

stang94X · Jan 16, 2009

rob10s2 said:
anyone know this pulley size?

go to www.928motorsports.com and look at the pulleys they have

Venom351R · Jan 16, 2009

rob10s2 said:
well vortech used to make a 5-6 psi kit with an s trim, i think i have that one, i bought the car with the blower on it. but i could have the 6-8 one and be seeing 6 b/c of the full exhaust and tfs intake manifold. but back to the question, will 10 lbs get me where i want to be? anyone know this pulley size?

That was the A Trim Vortech

LAFENATU · Jan 17, 2009

I was just about to say that. The A-trim has not been sold for years..

Jrgunn5150 · Jan 17, 2009

The SC is though, and I've noticed alot of people calling it an Strim.

Belt slip is likely too.

Venom351R · Jan 17, 2009

It should say right on the Tag on the head unit for which one it is.

hottwheels04 · Jan 18, 2009

they still do offer a 6-8 psi kit the sc trim, its $2,900 they have it on summitracings website and ive seen it advertised in a few mags still its just an updated kit strim with the 6psi pulley basic kit, doesnt come with anftercooler or a smaller pulley.