TPIS Headers
Thread Starter
Melting Slicks
Joined: Mar 2001
Posts: 3,247
Likes: 44
From: Parkland Florida
Corvette Challenge Champ-01
Dragster Challenge Champ-06
TPIS Headers
Put TPIS Headers and catback exhaust on my 85 bone stock Corvette. Put the catback exhaust on first. Car seemed to run basically the same numbers at the track as it did before with the stock exhaust but with a better sound. Put the TPIS headers on last week, took it to the track and slowed down a tenth to a tenth and a half. Sixty foot was still the same 1.85 on the average. Now this is basically a bone stock 85 Corvette coupe with stock heads and cam, factory 3:07 rear. The car has always sixty footed well due the factory 2400 stall converter, only offered that year. I realize with these headers that the primary tubes are 1 3/4" and really scavenge alot of exhaust gas throught the exhaust. This to me would create a lean condition, therefore telling the computer in the car to retard the timing. What would be my next move or mod to solve this problem? By the way the car has run a best of 13.63 with a 1.796 sixty foot time. This was with a 160 thermostat, BFG Drag Radials at 22 lbs. and really good cold air. Thanks for any input
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: TPIS Headers (Turbo Bob)
With the added exhaust gas flow (and so more flow through the motor) you likely need an AFPR to add some fuel at WOT.
It wouldn't hurt to add an SLP ram-air or at least a K&N with cut lid to help out on the inlet side.
Since you're in NJ I assume you have a cat; is it a hi-flow cat?
It wouldn't hurt to add an SLP ram-air or at least a K&N with cut lid to help out on the inlet side.
Since you're in NJ I assume you have a cat; is it a hi-flow cat?
Safety Car
Joined: Oct 2001
Posts: 4,763
Likes: 1
From: Connectivette
Re: TPIS Headers (65Z01)
Something is up for sure. I picked up .5 and 5 mph when I added my TPIS headers. Those results do however include a 2000 stall.
I've leaned my fuel out to 41 psi on my schreader, others like to bump it up. You may have to play with it a bit.
I assume you checked all the obvious stuff..............
cooked wire on the new headers
wires on correctly (snug)
etc. etc. etc.
I've leaned my fuel out to 41 psi on my schreader, others like to bump it up. You may have to play with it a bit.
I assume you checked all the obvious stuff..............
cooked wire on the new headers
wires on correctly (snug)
etc. etc. etc.
Thread Starter
Melting Slicks
Joined: Mar 2001
Posts: 3,247
Likes: 44
From: Parkland Florida
Corvette Challenge Champ-01
Dragster Challenge Champ-06
Re: TPIS Headers (65Z01)
Hi Jim,
I already have an open air lid with a K&N filter. Also the cat was on the car when I bought it so I assume that it is not a hi flow cat.
I already have an open air lid with a K&N filter. Also the cat was on the car when I bought it so I assume that it is not a hi flow cat.
Thread Starter
Melting Slicks
Joined: Mar 2001
Posts: 3,247
Likes: 44
From: Parkland Florida
Corvette Challenge Champ-01
Dragster Challenge Champ-06
Re: TPIS Headers (chucks88)
Hey Chuck,
Checked all the wires. There are on correctly, snug and no burned wires. I am running the stock computer chip in the car. I have a Hypertech chip Stage 2 I borrowed from a friend. Do you think this would help along with installing an AFR?
Checked all the wires. There are on correctly, snug and no burned wires. I am running the stock computer chip in the car. I have a Hypertech chip Stage 2 I borrowed from a friend. Do you think this would help along with installing an AFR?
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: TPIS Headers (Turbo Bob)
If you install that stage II chip you may need to back off the timing. It should give you more fuel and timing, based on a 160 deg stat but not on exhaust system mods. BTW, I just sold my stage II chip and installed the stock unit again.
So you will still need an AFPR. As Chuck indicated, take it to the track and tune fuel pressure for best trap speed.
So you will still need an AFPR. As Chuck indicated, take it to the track and tune fuel pressure for best trap speed.
