almost stock L98
Thread Starter
Instructor
Joined: Feb 2005
Posts: 162
Likes: 0
From: jacksonville N.C.
almost stock L98
I'm modifying my 89' L98. so far it has a BBk T/B and chambered mufflers. i just ordered 13/4" full length headers, a 2.5" exhaust w/ no cats, a T/B flow increaser, a Jet chip, a Lingenfelter hyd. roller cam kit, an SLP cold air intake, and aluminum high flow intake runners. im lookin for about 390-400 RWHP. what else can i do?
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
In addition to the current and intended mods try:
1) the small mods
-eliminate the "frisbee" from the water pump pulley
-install Al underdrive crank and overdrive alt pulleys
-go to a 160deg T-stat and fan switch
-gut the MAF
-install an AFPR to tune fuel flow at WOT
2) heads
-either port, polish and work your stock #113s
-or go with after-market heads with around 185cc ports
-RRs with the proper ratio for your valve springs & cam
3) ignition
-HyperTech coil/cap/rotor
-performance wires
-cut back stock style AC Delco plugs
You may need a custom chip burn and larger fuel injectors as you approach the top end of your performance target.
BTW, what LPE cam are you using?
Is the valve train stock?
1) the small mods
-eliminate the "frisbee" from the water pump pulley
-install Al underdrive crank and overdrive alt pulleys
-go to a 160deg T-stat and fan switch
-gut the MAF
-install an AFPR to tune fuel flow at WOT
2) heads
-either port, polish and work your stock #113s
-or go with after-market heads with around 185cc ports
-RRs with the proper ratio for your valve springs & cam
3) ignition
-HyperTech coil/cap/rotor
-performance wires
-cut back stock style AC Delco plugs
You may need a custom chip burn and larger fuel injectors as you approach the top end of your performance target.
BTW, what LPE cam are you using?
Is the valve train stock?
Le Mans Master
Joined: Jan 2002
Posts: 5,320
Likes: 4
From: Kyle TX (Because Mojo Made me fill it in)
If you're looking for 390-400 rwhp, you're going to need a lot more than that. You're looking at somewhere near 490chp to get 390-400 rwhp.
Your stock TPI with hi-flow runners wont take you there so you will need a Super Ram, Miniram, or some form of better breathing intake.
The 350 displacement is probably not going to cut that kind of power either. You'll probably have to go 383 to get that kind of power.
You can port the stock 113 D-port heads with a bazooka and it will probably not flow enough air to make that kind of power.
Now if you're looking for 390-400 chp, you have a shot.
Dont mean to sound so negative, but Ive been beating myself to death trying to come up with the money it will take to build a 383 to hit 400rwhp.
Here's the build that I've found that looks promising. The guy is making 440rwhp and 415rwtq on this motor.
http://home.comcast.net/~pontiacgta/.../Newengine.htm
Your stock TPI with hi-flow runners wont take you there so you will need a Super Ram, Miniram, or some form of better breathing intake.
The 350 displacement is probably not going to cut that kind of power either. You'll probably have to go 383 to get that kind of power.
You can port the stock 113 D-port heads with a bazooka and it will probably not flow enough air to make that kind of power.
Now if you're looking for 390-400 chp, you have a shot.
Dont mean to sound so negative, but Ive been beating myself to death trying to come up with the money it will take to build a 383 to hit 400rwhp.
Here's the build that I've found that looks promising. The guy is making 440rwhp and 415rwtq on this motor.
http://home.comcast.net/~pontiacgta/.../Newengine.htm
Thread Starter
Instructor
Joined: Feb 2005
Posts: 162
Likes: 0
From: jacksonville N.C.
the LPE cam im getting is pretty aggresive, its part #489 and has lift and duration of 213/219 and 493/502. my valvetrain is stock, but im looking into 1.6 roller rockers, new valve springs and the such. any suggestions? thanks for the reply, i need the guidance from guys who have done all this before.
Thread Starter
Instructor
Joined: Feb 2005
Posts: 162
Likes: 0
From: jacksonville N.C.
another question, what kind and brand of fuel injectors should i run? and who makes a good fuel pump? ive looked at 36lb/hr injectors, but i really dont know what im lookin for. i need the help from you vette vets!
Race Director
Joined: Feb 2004
Posts: 12,518
Likes: 19
Originally Posted by jack the stripper
another question, what kind and brand of fuel injectors should i run? and who makes a good fuel pump? ive looked at 36lb/hr injectors, but i really dont know what im lookin for. i need the help from you vette vets!
I did an am very happy with the results.
Race Director
Joined: Feb 2004
Posts: 12,518
Likes: 19
[QUOTE=jack the stripper]what did you use to make big tq? i want to upgrade to an sr or mr, but i need more info on each.[/QUOTE
I am a fan of the superram and 219 cam. I stumbled upon this combo before everyone knew about it. Check some of the posts regarding long tube runners vs miniram vs superram. Lots of good info. I was very happy with my 350/slp runner combo I ran in the mid 90's. Ran 12.80 in the 1/4. More importantly, tons of fun to drive. My 1/4 mile greed caused me to upgrade to the super ram 383 combo. The long runners of the tpi promote torque.
I am a fan of the superram and 219 cam. I stumbled upon this combo before everyone knew about it. Check some of the posts regarding long tube runners vs miniram vs superram. Lots of good info. I was very happy with my 350/slp runner combo I ran in the mid 90's. Ran 12.80 in the 1/4. More importantly, tons of fun to drive. My 1/4 mile greed caused me to upgrade to the super ram 383 combo. The long runners of the tpi promote torque.
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Race Director
Joined: Feb 2004
Posts: 12,518
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The super ram will allow more usable rpm's as well as increased torque. I recommend it over the long tube runners. However, if budget is a concern you can get by with the long tubes till the wallet fattens. If you have the coin, "I" would recommend going to superram. Do not write the check yet though. If you car is a stick and you wish to spin some rpm, check with the miniram fans. This will give big hp. I do not wish to turn my motor above 5500 rpm. This is 1 reason I prefer the sr.If memory serves 219 cam works w/stock pistons. Always check with clay though.
Burning Brakes
Joined: Sep 2001
Posts: 981
Likes: 0
From: Anderson South Carolina
You might want to reconsider your goal.
You can get the power you are looking for, but it's gona cost.
Horsepower is a different subject, as HP is a product of torque and RPM. To compute HP you take torque times RPM divided by 5252.
If you increase the rpm by changing the length/volume of the intake runners and better cam, and change the torque by increasing the CID and compression ratio, you will produce more HP.
There is really no need to go to bigger injectors even on a 383 unless you go to a really wild cam, better heads and clean exhaust.
Just my 2 cents.
vettmike
You can get the power you are looking for, but it's gona cost.
Horsepower is a different subject, as HP is a product of torque and RPM. To compute HP you take torque times RPM divided by 5252.
If you increase the rpm by changing the length/volume of the intake runners and better cam, and change the torque by increasing the CID and compression ratio, you will produce more HP.
There is really no need to go to bigger injectors even on a 383 unless you go to a really wild cam, better heads and clean exhaust.
Just my 2 cents.
vettmike
Racer
Joined: Aug 2004
Posts: 252
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From: Corpus Christi TX
With jack the stripper's original combo(plus 65Z01's suggestions), do you guys think 390-400 crank hp is a reasonable goal? I'm actually looking at doing a similar setup and thats what I'd like to hit.
Race Director
Joined: Feb 2004
Posts: 12,518
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Originally Posted by super89
With jack the stripper's original combo(plus 65Z01's suggestions), do you guys think 390-400 crank hp is a reasonable goal? I'm actually looking at doing a similar setup and thats what I'd like to hit.
Racer
Joined: Jan 2005
Posts: 312
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From: Las Vegas / Scotland
What's tha fascination with rwhp? The L98 was designed as a stump puller, not a quad cam 7000rpm high tech engine.
Unless you are going to change the whole way the car drives and seriously reduce the rear axle ratio you should aim for the high torque figures - that'll give you the acceleration as well as driveability that you are looking for. When Mr Mustang or Mr Subaru pulls alongside you want to just hit the gas and pull away - watching his hood rise and fall as he/she pulls the gears to try and keep up
I've driven too many Euro cars with lots of rwhp and poor torque figures and believe me, they get to be a real pita after a while.
Steve
Unless you are going to change the whole way the car drives and seriously reduce the rear axle ratio you should aim for the high torque figures - that'll give you the acceleration as well as driveability that you are looking for. When Mr Mustang or Mr Subaru pulls alongside you want to just hit the gas and pull away - watching his hood rise and fall as he/she pulls the gears to try and keep up
I've driven too many Euro cars with lots of rwhp and poor torque figures and believe me, they get to be a real pita after a while.
Steve
Race Director
Joined: Feb 2004
Posts: 12,518
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Originally Posted by stevec4
What's tha fascination with rwhp? The L98 was designed as a stump puller, not a quad cam 7000rpm high tech engine.
Unless you are going to change the whole way the car drives and seriously reduce the rear axle ratio you should aim for the high torque figures - that'll give you the acceleration as well as driveability that you are looking for. When Mr Mustang or Mr Subaru pulls alongside you want to just hit the gas and pull away - watching his hood rise and fall as he/she pulls the gears to try and keep up
I've driven too many Euro cars with lots of rwhp and poor torque figures and believe me, they get to be a real pita after a while.
Steve
Unless you are going to change the whole way the car drives and seriously reduce the rear axle ratio you should aim for the high torque figures - that'll give you the acceleration as well as driveability that you are looking for. When Mr Mustang or Mr Subaru pulls alongside you want to just hit the gas and pull away - watching his hood rise and fall as he/she pulls the gears to try and keep up
I've driven too many Euro cars with lots of rwhp and poor torque figures and believe me, they get to be a real pita after a while.
Steve
What he said.