Increase HP
Thread Starter
Advanced
Joined: Dec 2007
Posts: 80
Likes: 0
From: Birmingham AL
Increase HP
Increase HP
New to forum so hope I’m doing this right. Got my first Corvette last year 91 Coupe, 6spd, L98, 3:42 rear end , performance handling package, modifications: ignition module, ported exhaust manifold and ported cylinder heads , ported induction system, forged pistons, severe duty rod bolts, SS race camshaft( all info I have on camshaft) high pressure oil pump, custom chip, guted catalytic, ultra flow mufflers, K&N filter. These mods are from the work order which is all the information I have other than the owner told me the engine was built loose and to run 20w50 oil.
Looks like stock HP is 250 and torque about 340. Had the car dynode and hp was 260 and torque 360. So here’s the question. Shouldn’t I have more hp and torque with these mods? How can I increase HP and torque with going into the engine or adding a blower?
Thanks
Jim
New to forum so hope I’m doing this right. Got my first Corvette last year 91 Coupe, 6spd, L98, 3:42 rear end , performance handling package, modifications: ignition module, ported exhaust manifold and ported cylinder heads , ported induction system, forged pistons, severe duty rod bolts, SS race camshaft( all info I have on camshaft) high pressure oil pump, custom chip, guted catalytic, ultra flow mufflers, K&N filter. These mods are from the work order which is all the information I have other than the owner told me the engine was built loose and to run 20w50 oil.
Looks like stock HP is 250 and torque about 340. Had the car dynode and hp was 260 and torque 360. So here’s the question. Shouldn’t I have more hp and torque with these mods? How can I increase HP and torque with going into the engine or adding a blower?
Thanks
Jim
Melting Slicks
Joined: Dec 2004
Posts: 2,954
Likes: 2
From: Obama=death for America
If you don't have a good exhaust system on there, that will definitely keep the HP #'s down. By upgrading the engine, you now need a good exhaust system that will allow all that power to be released. If you've got the money, throw on a superram and you'll really wake your car up. Also, throw on a good set of headers and you'll be good to go.
Le Mans Master
Joined: Oct 2004
Posts: 7,706
Likes: 485
From: Everett WA
C4 of Year Finalist (appearance mods) 2019
Most likely your stock rating is at the crankshaft and of course your dyno is rear-wheel HP thus a significant difference.
For example on my 95 LT1 the "stock" rating is 300HP but this is at the crank. On a mustang dyno it registered 252. After installing long tube headers and a cam and a tune, my rear wheel hp on a mustang dyno = 292.
For example on my 95 LT1 the "stock" rating is 300HP but this is at the crank. On a mustang dyno it registered 252. After installing long tube headers and a cam and a tune, my rear wheel hp on a mustang dyno = 292.
Team Owner
Joined: Sep 2001
Posts: 62,126
Likes: 1,727
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Need to know what type chassis dyno you used, Mustang or Dynojet? Should be on the graph, or ask whomever did it.
Those are rear wheel numbers you quoted, which should be at least 15-16% lower than the engine flywheel output (I'm assuming dynojet).
The stock number you have quoted is the original flywheel output, so there is a discrepancy.
We won't be able to tell what it can make without more details on the camshaft. That would be the first thing to find out. Then ask what was done to the intake system, ported or were any parts replaced with aftermarket?
Exhaust system needs headers, they will really make a difference with these other mods already done.
Those are rear wheel numbers you quoted, which should be at least 15-16% lower than the engine flywheel output (I'm assuming dynojet).
The stock number you have quoted is the original flywheel output, so there is a discrepancy.
We won't be able to tell what it can make without more details on the camshaft. That would be the first thing to find out. Then ask what was done to the intake system, ported or were any parts replaced with aftermarket?
Exhaust system needs headers, they will really make a difference with these other mods already done.
Thread Starter
Advanced
Joined: Dec 2007
Posts: 80
Likes: 0
From: Birmingham AL
Increase HP
Appreciate the advice. So more questions and info.
Best Superram for this application?
Regular or Long tube headers?
DynoJet Dyno.
So should have about 300 HP at FW.
Air Fuel Ratio is 14 told this to lean richer would increase HP.
Does Chip need to be reprogrammed?
Mods done 10 years ago only available info on cam is it was a “mild cam.”
Anyway to tell how much HP can be increased with this info.
Here’s all info from work order on engine:
Do Top end Kit:
Port exhaust manifolds, Port cylinder heads, Port complete induction system, Remove engine Build 355 short block w/stage II cylinder heads and ss race cam kit. TPIS 8mm wires, rapid fire plugs. Other info on work order mentioned in original post.
Thanks for all the input I really appreciate it.
Jim
Best Superram for this application?
Regular or Long tube headers?
DynoJet Dyno.
So should have about 300 HP at FW.
Air Fuel Ratio is 14 told this to lean richer would increase HP.
Does Chip need to be reprogrammed?
Mods done 10 years ago only available info on cam is it was a “mild cam.”
Anyway to tell how much HP can be increased with this info.
Here’s all info from work order on engine:
Do Top end Kit:
Port exhaust manifolds, Port cylinder heads, Port complete induction system, Remove engine Build 355 short block w/stage II cylinder heads and ss race cam kit. TPIS 8mm wires, rapid fire plugs. Other info on work order mentioned in original post.
Thanks for all the input I really appreciate it.
Jim
Le Mans Master
Joined: Aug 2003
Posts: 9,884
Likes: 3
From: Magnolia Mississippi
St. Jude '03-'04-'05-'06-'07
If you want more info: Learn to use the Search function, there's ton's of info from all points of view as well as hardware, performance, upgrades, and the like... your list of questions should give you hrs of reading and points of view...
Le Mans Master
Joined: Dec 2003
Posts: 5,867
Likes: 17
From: Phoenix Arizona
Appreciate the advice. So more questions and info.
Best Superram for this application?
Regular or Long tube headers?
DynoJet Dyno.
So should have about 300 HP at FW.
Air Fuel Ratio is 14 told this to lean richer would increase HP.
Does Chip need to be reprogrammed?
Mods done 10 years ago only available info on cam is it was a “mild cam.”
Anyway to tell how much HP can be increased with this info.
Here’s all info from work order on engine:
Do Top end Kit:
Port exhaust manifolds, Port cylinder heads, Port complete induction system, Remove engine Build 355 short block w/stage II cylinder heads and ss race cam kit. TPIS 8mm wires, rapid fire plugs. Other info on work order mentioned in original post.
Thanks for all the input I really appreciate it.
Jim
Best Superram for this application?
Regular or Long tube headers?
DynoJet Dyno.
So should have about 300 HP at FW.
Air Fuel Ratio is 14 told this to lean richer would increase HP.
Does Chip need to be reprogrammed?
Mods done 10 years ago only available info on cam is it was a “mild cam.”
Anyway to tell how much HP can be increased with this info.
Here’s all info from work order on engine:
Do Top end Kit:
Port exhaust manifolds, Port cylinder heads, Port complete induction system, Remove engine Build 355 short block w/stage II cylinder heads and ss race cam kit. TPIS 8mm wires, rapid fire plugs. Other info on work order mentioned in original post.
Thanks for all the input I really appreciate it.
Jim
It sounds like your chip is horrible - probably an off-the-shelf Hypertech, etc. from 10 years ago. Contact a programmer like Ron Zimmer at Z Industries and have him burn a chip for you based on your mods - this makes a huge difference. Meanwhile, don't thrash your current setup running that lean.
Best of luck!
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
Team Owner
Joined: Sep 2001
Posts: 62,126
Likes: 1,727
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Best Superram for this application?
There is only one "superram".
Regular or Long tube headers?
Only longtubes, never use shorty headers.
Does Chip need to be reprogrammed?
Very likely it was already done when the cam was changed. A new one wont do any good if the tuner doesnt know all the specs either.
Anyway to tell how much HP can be increased with this info.
Here’s all info from work order on engine:
Do Top end Kit:
Port exhaust manifolds, Port cylinder heads, Port complete induction system, Remove engine Build 355 short block w/stage II cylinder heads and ss race cam kit.
Intake and exhaust work are all you should consider. Either replace the intake parts with aftermarket pieces, or the whole thing with a different type of intake. Read my website.
There is only one "superram".
Regular or Long tube headers?
Only longtubes, never use shorty headers.
Does Chip need to be reprogrammed?
Very likely it was already done when the cam was changed. A new one wont do any good if the tuner doesnt know all the specs either.
Anyway to tell how much HP can be increased with this info.
Here’s all info from work order on engine:
Do Top end Kit:
Port exhaust manifolds, Port cylinder heads, Port complete induction system, Remove engine Build 355 short block w/stage II cylinder heads and ss race cam kit.
Intake and exhaust work are all you should consider. Either replace the intake parts with aftermarket pieces, or the whole thing with a different type of intake. Read my website.
Thread Starter
Advanced
Joined: Dec 2007
Posts: 80
Likes: 0
From: Birmingham AL
I'm no expert, but I'd say Accel Superram or TPIS Miniram, long tube headers, cam w/ around .220 duration (at .050). 1.6 roller rockers. Don't forget to also go with a 52 MM throttle body.
It sounds like your chip is horrible - probably an off-the-shelf Hypertech, etc. from 10 years ago. Contact a programmer like Ron Zimmer at Z Industries and have him burn a chip for you based on your mods - this makes a huge difference. Meanwhile, don't thrash your current setup running that lean.
Best of luck!
It sounds like your chip is horrible - probably an off-the-shelf Hypertech, etc. from 10 years ago. Contact a programmer like Ron Zimmer at Z Industries and have him burn a chip for you based on your mods - this makes a huge difference. Meanwhile, don't thrash your current setup running that lean.
Best of luck!
Jim
Thread Starter
Advanced
Joined: Dec 2007
Posts: 80
Likes: 0
From: Birmingham AL
Best Superram for this application?
There is only one "superram".
Regular or Long tube headers?
Only longtubes, never use shorty headers.
Does Chip need to be reprogrammed?
Very likely it was already done when the cam was changed. A new one wont do any good if the tuner doesnt know all the specs either.
Anyway to tell how much HP can be increased with this info.
Here’s all info from work order on engine:
Do Top end Kit:
Port exhaust manifolds, Port cylinder heads, Port complete induction system, Remove engine Build 355 short block w/stage II cylinder heads and ss race cam kit.
Intake and exhaust work are all you should consider. Either replace the intake parts with aftermarket pieces, or the whole thing with a different type of intake. Read my website.
There is only one "superram".
Regular or Long tube headers?
Only longtubes, never use shorty headers.
Does Chip need to be reprogrammed?
Very likely it was already done when the cam was changed. A new one wont do any good if the tuner doesnt know all the specs either.
Anyway to tell how much HP can be increased with this info.
Here’s all info from work order on engine:
Do Top end Kit:
Port exhaust manifolds, Port cylinder heads, Port complete induction system, Remove engine Build 355 short block w/stage II cylinder heads and ss race cam kit.
Intake and exhaust work are all you should consider. Either replace the intake parts with aftermarket pieces, or the whole thing with a different type of intake. Read my website.
Thank you
Jim
