always faster

Lets make a small poll for this one
I got a 383 and im putting down 490whp/461wtq with a stock untouched ls6 intake and stock untouched 78mm tb.So i was looking to improve my intake.

Note:
1-I did not use a Fast 90 or 92 because i had one on my first setup and the lower sheel cracked twice because of the cheap plastic.
2-I did not use a Fast 102 because after some test fit,it was rubbing/hitting my cowl.There is no way i would cut my car for a intake and will not use shorter engine mount.

So the TPIS 90mm ls6 was the way to go.A solid ls6 gm base with a 90mm opening.But they are kinda rare in the used market.Ive found one a couple weeks ago for a faire price and bought it.I will use a 90mm ls2 tb.Both will be professionaly ported and the transition between the tb and the intake opening will be seem-less.

So simple question:

After some tune adjustment ,how much whp should i gain ???
Hoping for at least 20whp

Thanks
Eric

dankhts

I only picked up 11 rwhp on my heads/cam C5, from about 3,500rpm and up, lost a bit below that though, ported Fast 92/90 and a well respected tuner.....I was hoping for more but I got about what he told me to expect....

JoeyG

Id say 10hp but more importantly 25lbft with additional tuning.

always faster

Well kinda depressing...10whp...
I guess that the 25 torque is something good.

always faster

Would it hurt me a lot by skipping the porting job on the intake ???I mean if spending 125$ + both shipping from canada for a port job is useless i would not do it.

I could just slap the ported ls2 tb on it and thats it.Maybe tring to make a seem-less transition myself but left the intake in stock form.

PRE-Z06

Curious what heads you're running?
FWIW here's my results from an LS6 to a 92...
http://forums.corvetteforum.com/perf...-maf-10hp.html

always faster

Im running:
PRC LS6(243) stage 2.5 : http://www.texas-speed.com/p-4-prc-s...ted-heads.aspx
383 ci built by TSP(all callies) 11:1 CR
Cam: 240/244 ,.615"/.619" @ 113 lsa (EXR lobe)
All the support mod(ARH 1 7/8 ,Vararam,morel lifter,manton custom pushrods, etc etc)
Built tr6060/c6z diff complete setup,twin disc clutch,adj master,poly tube coupler etc etc)

No cheap parts but did wanted to say simple.

PRE-Z06

Sounds like a solid build and the intake is definitely the bottle neck, so you should see some better gains. Have you ever logged your kpa?

always faster

Better gains, well finally something positive to hear
I dont know the KPA reading since im do not tune the car.

If i can have someting in the 505whp/480wtq minimum range, i ll be happy

mchicia1

Did you use the button head bolts on the valley when you had your first fast 90? It's a common problem for people not to install them and they end up cracking the intake.

Anyway, on a 383, you will pick up 30 from 4k and up with a fast/ls2 tb, no doubt about that. I even gained 25 on my little 346.