1991 Corvette Mods
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3rd Gear
Joined: Jun 2018
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From: Missouri
1991 Corvette Mods
Hey fellas I'm kinda new to the Corvette world but I've got a 1991 Vette that we've started doing some mods to and I wanted to get some ideas of the direction I'm going before I get to far into it. I've got a set of Fast Burn heads and a Comp Xtreme Energy Cam were about to install. I was wondering what injector size I should go with? Also what company is the best to go with for Tuning?
Team Owner
Joined: Jul 2004
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From: Hartford WI
Before you go there, have you given any thought to finding a tuner to advise you on what combination you need? You might have to do intakes and headers to take advantage of the heads and maybe the cam profile should be different. You can't just slap a bunch of parts together and hope they all work well.
As to tuning, there are a couple I know of. One is at Joe Hornick Racing in SC. Another one that might still do it is Hitech Motorsport in MN and maybe TPIS in MN?
As to tuning, there are a couple I know of. One is at Joe Hornick Racing in SC. Another one that might still do it is Hitech Motorsport in MN and maybe TPIS in MN?
Team Owner
Joined: Dec 2000
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From: SE NY
Cruise-In II Veteran
Congrats on your '91 Vette and welcome to the Forum. Is it a 6-spd or an A4?
Since you are considering doing heads & cam, for sure you will need a little fuel & air and definitely exhaust work. With stock heads, cam & headers I was able to coax my prior '88 up to 300chp.
If you are looking for the most from your L98 you should get north of 350-360chp gain which is a nice bump from the stock 230.
BTW, some years ago TPIS did an article on such a build with excellent results.
Since you are considering doing heads & cam, for sure you will need a little fuel & air and definitely exhaust work. With stock heads, cam & headers I was able to coax my prior '88 up to 300chp.
If you are looking for the most from your L98 you should get north of 350-360chp gain which is a nice bump from the stock 230.
BTW, some years ago TPIS did an article on such a build with excellent results.
Team Owner
Joined: Sep 2001
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
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Not enough information here to go with. What is the goal here? Need the specs on the camshaft.
What of this will you be doing yourself? What are you going to do with the intake manifold to keep it from choking the rest of the motor?. What is being done with the exhaust? Cannot recommend injectors without knowing what youre wanting as the finished product from the car.
What of this will you be doing yourself? What are you going to do with the intake manifold to keep it from choking the rest of the motor?. What is being done with the exhaust? Cannot recommend injectors without knowing what youre wanting as the finished product from the car.
Team Owner
Joined: Sep 2001
Posts: 62,137
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
I wouldnt put that cam in a 350 TPI car. No way. I'd put it into a 383 with a Miniram on it.
What are the goals for the car? Power numbers? 1/4mi? and how much are you doing yourself?
What are the goals for the car? Power numbers? 1/4mi? and how much are you doing yourself?
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From: Hartford WI
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From: altered state
St. Jude Donor '05
Return that cam and get one that works with the long tube runner intake if youre going to keep it. By the time that cam stars working your intake is done.
Plus those cams are hard on parts period., not a fan. Surprised Comp recommended that.
You may want to upgrade your torque converter stall speed depending on final choice. What rear end gear do you have?
Measure twice, cut once
Plus those cams are hard on parts period., not a fan. Surprised Comp recommended that.
You may want to upgrade your torque converter stall speed depending on final choice. What rear end gear do you have?
Measure twice, cut once
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Joined: Nov 2003
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From: Overland Park Kansas
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So now we know it's an automatic -- meant for street use. Still withholding on the intake, gearing, and exhaust config.
The only thing I'll throw out there on injectors is that L98's run batch fire -- which is capable of loading fuel into the intake runners TWICE per 4-cycle (cam) revolution. Most L98 owners ignore this fact. That means injectors can perform as if they double sequential setups. (One of the few "mod" advantages of the L98s. Plus, you can achieve increases via AFPR.) 24lb injectors powered "legacy" member Corky's vette to 500hp. My 383 has 24lb SVO's (25.5lb) which still have PA-LENTY of headroom.
Longtube TPI owners stay around/below 220 duration cams. 350 short-runner-intake cars generally stay below 230. Yeah...more if all-out-racing. Stay on the smaller side to retain idle, off-idle, and low-rpm performance.
The only thing I'll throw out there on injectors is that L98's run batch fire -- which is capable of loading fuel into the intake runners TWICE per 4-cycle (cam) revolution. Most L98 owners ignore this fact. That means injectors can perform as if they double sequential setups. (One of the few "mod" advantages of the L98s. Plus, you can achieve increases via AFPR.) 24lb injectors powered "legacy" member Corky's vette to 500hp. My 383 has 24lb SVO's (25.5lb) which still have PA-LENTY of headroom.
Longtube TPI owners stay around/below 220 duration cams. 350 short-runner-intake cars generally stay below 230. Yeah...more if all-out-racing. Stay on the smaller side to retain idle, off-idle, and low-rpm performance.