L98 performance suggestions
Le Mans Master
Joined: Jul 2004
Posts: 7,163
Likes: 61
From: NH
St. Jude Donor '14
Team Owner
Joined: Oct 2004
Posts: 35,065
Likes: 0
From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
Safety Car
Joined: Jan 2006
Posts: 3,566
Likes: 4
From: Mt Laurel NJ
St. Jude Donor '06-'07
Here is what I would do. Pull the engine, and find a shop that can rebuilt the bottom end. W/ 172,000 miles, I'am sure it needs it. You can have it bored .30 over or go w/ a 383 kit. Look around on the for sale section here and at thirdgen.org for a set of 113 alum heads. Have the heads rebuilt w/ LT4 hot cam springs, and pick a cam (lots of good advice above). Then find a modifed LT1 intake, and a set of headers, and you should be good to go.
Randy
Randy
Burning Brakes
Joined: Nov 2003
Posts: 914
Likes: 1
From: Redding Ca
I read your initial question to say you wanted to stay with the TPI because you did not want to mess up the comuter (read that "chip").
In my opinion, the TPI is THE limiting factor in an L98. A Super Ram will not affect your computer at all. Nor will any larger aftermarket intake and runners such as TPIS, etc. But a big cam change would. I think you'd be very safe with an Accel 211, TPIS ZZ9 or similar cam. Although I have not run them, I believe they are excellent mild cams (I have Accel 219 and it will run with a stock chip, although I have a custom chip).Once you are inside the engine, you might as well bite the bullet and do a cam too.
No one has ever complained in this forum about too much power. My experience has been the engine usually does not run a strongly as hoped for, so i suggest plan a bit more than you think you need, and just find some competent local help. It is not that expensive and you will be driving a long time. This forum is a great place for that kind of help too.
In my opinion, the TPI is THE limiting factor in an L98. A Super Ram will not affect your computer at all. Nor will any larger aftermarket intake and runners such as TPIS, etc. But a big cam change would. I think you'd be very safe with an Accel 211, TPIS ZZ9 or similar cam. Although I have not run them, I believe they are excellent mild cams (I have Accel 219 and it will run with a stock chip, although I have a custom chip).Once you are inside the engine, you might as well bite the bullet and do a cam too.
No one has ever complained in this forum about too much power. My experience has been the engine usually does not run a strongly as hoped for, so i suggest plan a bit more than you think you need, and just find some competent local help. It is not that expensive and you will be driving a long time. This forum is a great place for that kind of help too.
Last edited by GeosFun; Nov 6, 2007 at 02:33 PM.
Team Owner
Joined: Oct 2004
Posts: 35,065
Likes: 0
From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
No one has ever complained in this forum about too much power. My experience has been the engine usually does not run a strongly as hoped for, so i suggest plan a bit more than you think you need, and just find some competent local help. It is not that expensive and you will be driving a long time. This forum is a great place for that kind of help too.
People are not happy with their mods because they do not take the time to research the best COMBINATION of what they are doing. I believe people tend to put too much cam, or too much head, or too much valve, or too much injector, or something to that effect into their build.
Then when the car has dead spots throughout the range, bogs on acceleration, ect....
This was typical when I was a kid and people would throw 850 CFM carbs and larger on 350s and wondered why it ran like crap.
Big enough is usually enough. Too big is bad.
Intermediate
Joined: Nov 2007
Posts: 28
Likes: 0
From: Dallas Texas
Intermediate
Joined: Nov 2007
Posts: 28
Likes: 0
From: Dallas Texas
Having gone through months of research, second guessing, rethinking, and re-assesing, I have come to a conclusion:
People are not happy with their mods because they do not take the time to research the best COMBINATION of what they are doing. I believe people tend to put too much cam, or too much head, or too much valve, or too much injector, or something to that effect into their build.
Then when the car has dead spots throughout the range, bogs on acceleration, ect....
This was typical when I was a kid and people would throw 850 CFM carbs and larger on 350s and wondered why it ran like crap.
Big enough is usually enough. Too big is bad.
People are not happy with their mods because they do not take the time to research the best COMBINATION of what they are doing. I believe people tend to put too much cam, or too much head, or too much valve, or too much injector, or something to that effect into their build.
Then when the car has dead spots throughout the range, bogs on acceleration, ect....
This was typical when I was a kid and people would throw 850 CFM carbs and larger on 350s and wondered why it ran like crap.
Big enough is usually enough. Too big is bad.
Go to MSD Ignitions website and there is a Injector calulator that can tell you exactly what CFM you need to support your engine and what Injectors as well.
