C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

L98 camshaft

Thread Tools
 
Search this Thread
 
Old Jun 23, 2009 | 03:37 PM
  #1  
supercharged90tpi's Avatar
supercharged90tpi
Thread Starter
Cruising
 
Joined: Jun 2009
Posts: 12
Likes: 0
Default L98 camshaft

Hi all !

I've a 1990 L98 supercharged and have only 312 hp on the dyno
my car is stock, it only has the paxton supercharger, nothing else

I know that to put a nice camshaft can easy get 30-50 more hp,
but i'm a daily driver and want to keep a good idle and a correct gaz emmission.. i live in switzerland and every 2 years, i've to do an gaz emission control with 0 C.O.

thanks all
Bye
Reply
Old Jun 23, 2009 | 08:07 PM
  #2  
pologreen1's Avatar
pologreen1
Team Owner
15 Year Member
 
Joined: Dec 2007
Posts: 20,974
Likes: 261
Default

Unless or even if it is RWHP you talking that sounds a little low. are you sure it does need need regular maintance or a real tune?

Also try the F/I section
Reply
Old Jun 23, 2009 | 08:56 PM
  #3  
Former Ford Boy's Avatar
Former Ford Boy
Advanced
 
Joined: Nov 2004
Posts: 79
Likes: 0
From: Richmond VA
Default

Originally Posted by supercharged90tpi
Hi all !

I've a 1990 L98 supercharged and have only 312 hp on the dyno
my car is stock, it only has the paxton supercharger, nothing else
If those numbers are at the rear wheels, I am not sure they are that far off depending on how much boost you're making with the s/c.

Using a 15% parasitic loss factor, your 312 rwhp equals about 365 at the crank. It works out to roughly a 49% increase over the stock motor.

Regards,
Phillip
Reply
Old Jun 24, 2009 | 12:49 AM
  #4  
ross.rosseland's Avatar
ross.rosseland
Instructor
 
Joined: Mar 2005
Posts: 129
Likes: 0
From: Layton ut
Default

Your stock heads flow about 196 cfm on the intake. Since you get about 2 hp/cfm, you are maxing out your heads.

Put in some larger aftermarket heads and get some more lift on your cam with some 1.65 roller rockers and you'll be amazed at the difference. Of course you'll probably have to retune after that. A better intake will help a lot, too.

What are your HP goals?
Reply
Old Jun 24, 2009 | 10:07 AM
  #5  
Master__Shake_'s Avatar
Master__Shake_
Pro
 
Joined: Jan 2008
Posts: 584
Likes: 1
From: Near Lockport NY Black 1986 Coupe
Default

Have you also considered installing an air/air or air/water intercooler? It will cool down the air charge that the blower is heating by friction, therefore allowing you to run higher boost on the same octane gas. Cooler air means more power.

The heads/cam idea will work too, as long as you keep lower compression heads and they complement eachother. Dart/AFR/Brodix are all nice choices if you can find 76cc combustion chambers, and run a cam with .55x lift for 400+rwhp.
Reply
Old Jun 27, 2009 | 11:37 AM
  #6  
supercharged90tpi's Avatar
supercharged90tpi
Thread Starter
Cruising
 
Joined: Jun 2009
Posts: 12
Likes: 0
Default

Originally Posted by ross.rosseland
Your stock heads flow about 196 cfm on the intake. Since you get about 2 hp/cfm, you are maxing out your heads.

Put in some larger aftermarket heads and get some more lift on your cam with some 1.65 roller rockers and you'll be amazed at the difference. Of course you'll probably have to retune after that. A better intake will help a lot, too.

What are your HP goals?
ok thanks for the informations,
my goal is about 400 - 420 jp

see ya
Reply
Old Jun 27, 2009 | 11:54 AM
  #7  
Vic'89's Avatar
Vic'89
Safety Car
25 Year Member
Conversation Starter
All Eyes On Me
 
Joined: Jun 2000
Posts: 4,870
Likes: 25
From: Long Island, NY
Default

Originally Posted by pologreen1
Unless or even if it is RWHP you talking that sounds a little low. are you sure it does need need regular maintance or a real tune?

Also try the F/I section
How is that a low RWHP number for a stock Vette with a supercharger ? Seems right to me.

Bone stock was about 200 RWHP, he picked up 120 HP. Not bad for a Paxton at all.

Car is good for high 11's.

Vic
Reply
Old Jun 27, 2009 | 11:57 AM
  #8  
cv67's Avatar
cv67
Team Owner
15 Year Member
 
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Default

Big improvement. Besides the L98 was designed for torque, S/C build even more. Who cares about the hp # anyway, it doesnt matter.

How does it run are you happy with it
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

10 Ugly Corvettes That We Still Kinda Love

 Joe Kucinski
story-1

Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

 Brett Foote
story-2

10 Things Every Corvette Owner Needs (2026 Edition)

 Michael S. Palmer
story-3

8 Most "Only Corvette Owners Understand" Quirks and Problems

 Pouria Savadkouei
story-4

10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

 Joe Kucinski
story-5

How Much Horsepower Every Corvette Engine "LOST" in 1972

 Joe Kucinski
story-6

Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

 Michael S. Palmer
story-7

Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

 Joe Kucinski
story-8

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-9

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
Old Jun 27, 2009 | 12:12 PM
  #9  
c4cruiser's Avatar
c4cruiser
Team Owner
20 Year Member
Veteran: Army
 
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
Default

Do you still have the stock exhaust system on the car? A clogged catalytic converter could cause a drop in HP numbers. The stock exhaust system is somewhat restrictive with the cats and the single pipe after the main cat.

If you are not required to have a visual check/inspection of the exhaust system, you might consider a true dual exhaust system using high flow cats and maybe even headers. If the factory air pump is required by Swiss emissions or vehicle laws, Hedman makes a set of headers with connections for the air pump.
Reply

Get notified of new replies

To L98 camshaft





All times are GMT -4. The time now is 12:23 PM.

story-0
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-1
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE
story-2
10 Things Every Corvette Owner Needs (2026 Edition)

Slideshow: 10 great gifts Corvette enthusiasts actually want for Father's Day!

By Michael S. Palmer | 2026-06-03 15:43:40


VIEW MORE
story-3
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE
story-4
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

Slideshow: 10 reasons why the C6 Z06 is still a performance benchmark after 20 years.

By Joe Kucinski | 2026-05-27 17:20:09


VIEW MORE
story-5
How Much Horsepower Every Corvette Engine "LOST" in 1972

Slideshow: How much horsepower every Corvette engine lost in 1972.

By Joe Kucinski | 2026-05-27 16:54:53


VIEW MORE
story-6
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE
story-7
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

Slideshow: The 10 most explosive Corvettes ever built based on power-to-weight ratio.

By Joe Kucinski | 2026-05-20 07:23:03


VIEW MORE
story-8
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-9
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE