Recipe for 420hp/490tq from L98
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Car: 1987 GTA Vert & 1991 GTA 5 Speed
Engine: 87 GTA-L98 91 GTA LB9
Transmission: GTA-700R4 & GTA T5
Recipe for 420hp/490tq from L98
I am sure everyone in here has seen this article but could someone tell me what is wrong with this set up to get 420 hp and that 490 tq from a L98.
I understand that you can just swap in an LS1 and get this but if you want to keep the original look in the engine bay and not have to change K member etc. this would seem the way to go.
http://www.gmhightechperformance.com...ck/page_2.html
I understand that you can just swap in an LS1 and get this but if you want to keep the original look in the engine bay and not have to change K member etc. this would seem the way to go.
http://www.gmhightechperformance.com...ck/page_2.html
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Car: 90 Formula
Engine: 305
Transmission: 700R4
Axle/Gears: 9 bolt/3.27
Re: Recipe for 420hp/490tq from L98
I was hoping for a follow up article of the motor installed in a car with at least chassis dyno numbers but just like projects Blue Thunder and Snowball, they just disappeared.
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Car: 87 GTA
Engine: L98
Transmission: 700R4
Axle/Gears: Dana M78 3.27 posi
Re: Recipe for 420hp/490tq from L98
Very impressive!
But the article is SUPER VAGUE about how it was done. No build specs or nothing.
Is it in print with more details or what?
But the article is SUPER VAGUE about how it was done. No build specs or nothing.
Is it in print with more details or what?
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Car: 1991 RS
Engine: 5.0
Transmission: 700r4
Re: Recipe for 420hp/490tq from L98
Thats why i don't read GM High Tech Performance anymore. It's all ls1 stuff. After Hunkins left the mag it's just wasn't the same. There is little to no third gen stuff any more. People need to realize we still exist and there is a large untapped market with us.
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Re: Recipe for 420hp/490tq from L98
Looks like pretty good numbers for the combination they used. Like was said above that is on an engine dyno with no accessories and using engine dyno headers. Strap that motor in a smog legal car with a full exhaust system and mufflers on a chasis dyno and the numbers will drop quite abit.
I think the motor combinations reported here on Third Gen are superior and are the direction in which to go.
I think the motor combinations reported here on Third Gen are superior and are the direction in which to go.
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Car: 1987 GTA Vert & 1991 GTA 5 Speed
Engine: 87 GTA-L98 91 GTA LB9
Transmission: GTA-700R4 & GTA T5
Re: Recipe for 420hp/490tq from L98
If you were forced to bet what do you think the #s would be in real world situation I guess Hp/tq on the ground is what I am after.
Also what is the most hp/tq anyone seen out of a L98?
What can one realistically expect to get from an L98 while keeping the stock/stealth appearance?
Ive seen these "kits" for what looks like bolt on hp upgrades for Mustangs. Is there nothing like that for 3rd gens? Maybe at least the C4 Corvette L98s. We could probably have something to work with if there were something for them.
Also what is the most hp/tq anyone seen out of a L98?
What can one realistically expect to get from an L98 while keeping the stock/stealth appearance?
Ive seen these "kits" for what looks like bolt on hp upgrades for Mustangs. Is there nothing like that for 3rd gens? Maybe at least the C4 Corvette L98s. We could probably have something to work with if there were something for them.
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Re: Recipe for 420hp/490tq from L98
Ray Bahacz is a trustworthy and knowledgeable engine builder, but I still think something is strange. There's no way that combo would run in the 11's in a 3500 lbs thirdgen, nor get 30+ miles per gallon. I would guess my previous combo with long tube runners would put out the same on a chassis dyno, and the best I could get it to run was 12.80 @ 108.50 at a sea level track, and it got 25 MPG on the highway. It put down 318 RWHP and 418 RWTQ.
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Car: 1987 GTA Vert & 1991 GTA 5 Speed
Engine: 87 GTA-L98 91 GTA LB9
Transmission: GTA-700R4 & GTA T5
Re: Recipe for 420hp/490tq from L98
I am using #s 215 HP @ 4400 RPM / 285 FT/LB @ 3200 RPM (MM5 Transmission) found at http://www.gtasourcepage.com/techspecs.html
for the L98. Does anyone know if these are ratings on the pavement or at the flywheel. I am assuming, I may be wrong, but doesnt "brake" hp/tq mean at the wheels?
Is there a standard today with the new car manufacturers use for hp/tq ratings? Is that at the flywheel or on the pavement?
for the L98. Does anyone know if these are ratings on the pavement or at the flywheel. I am assuming, I may be wrong, but doesnt "brake" hp/tq mean at the wheels?
Is there a standard today with the new car manufacturers use for hp/tq ratings? Is that at the flywheel or on the pavement?
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Car: 88 GTA "Cocaine"
Engine: 350 tpi
Transmission: 700r4
Axle/Gears: 3.27
Re: Recipe for 420hp/490tq from L98
heads $$$$$
intake runners $$$$$
cam lifters $$$$
domed pistons $$$$
injectors $
fuel pump afpr $$
big-o-headers
bad a-rockers
throttle body 54 and up
and some other stuff I can remember
then you still will have problems getting to 420(cool number) without someone who can put on a super bad tune on the prom
tpi is a street setup, if you want to race with it you are throwing money at the wrong system
not saying that it cannot be done- saying it cant be done without mucho denaro
intake runners $$$$$
cam lifters $$$$
domed pistons $$$$
injectors $
fuel pump afpr $$
big-o-headers
bad a-rockers
throttle body 54 and up
and some other stuff I can remember
then you still will have problems getting to 420(cool number) without someone who can put on a super bad tune on the prom
tpi is a street setup, if you want to race with it you are throwing money at the wrong system
not saying that it cannot be done- saying it cant be done without mucho denaro
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Re: Recipe for 420hp/490tq from L98
I am using #s 215 HP @ 4400 RPM / 285 FT/LB @ 3200 RPM (MM5 Transmission) found at http://www.gtasourcepage.com/techspecs.html
for the L98. Does anyone know if these are ratings on the pavement or at the flywheel. I am assuming, I may be wrong, but doesnt "brake" hp/tq mean at the wheels?
Is there a standard today with the new car manufacturers use for hp/tq ratings? Is that at the flywheel or on the pavement?
for the L98. Does anyone know if these are ratings on the pavement or at the flywheel. I am assuming, I may be wrong, but doesnt "brake" hp/tq mean at the wheels?
Is there a standard today with the new car manufacturers use for hp/tq ratings? Is that at the flywheel or on the pavement?
For an easy/cheap combo to get some nice numbers out of an L98 the Vortec heads/HSR combo and mild cam will produce some nice numbers for a decent price. or you can go with a vortec tpi intake if you want to keep the TPI look.
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