C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

Top end performance question

Thread Tools
 
Search this Thread
 
Old Sep 9, 2002 | 03:55 AM
  #1  
Maurice's Avatar
Maurice
Thread Starter
Safety Car
25 Year Member
Conversation Starter
All Eyes On Me
Liked
 
Joined: Jan 2001
Posts: 3,569
Likes: 1
From: Hawaii
Default Top end performance question

I have a question about the top end performance of my car. I seem to be losing power at the higher RPM's and especially at higher speeds and higher RPM's. What would be some things to check into to find out what the heck is happening. My gut feeling is telling me it is my fuel pump isn't big enough to supply the amount of gas required. Any suggestions or anybody know how to tell if my fuel pump isn't big enough? My engine is a 502ci/502hp Chevy crate engine.

Thanks in advance
Maurice
Reply
Old Sep 9, 2002 | 04:09 AM
  #2  
Chuck Harmon's Avatar
Chuck Harmon
Melting Slicks
25 Year Member
Conversation Starter
All Eyes On Me
 
Joined: Apr 2000
Posts: 3,286
Likes: 8
From: San Jose California
Default Re: Top end performance question (Maurice)

Mount/tape a fuel pressure gauge to the inside of your cowl hood scoop where you can see it through the windshield and attach it to a "T" in your fule line at the carb.

More probable in my opinion is that you may have the same problem Jay, Tom, me, and certainly many others have had: A throttle bracket that has slipped at its rear left carb stud. Jay's cost his L88 about 50hp during his dyno run before he found it. I think it cost me 70hp when I compare my first Dyno Day to my recent 483rwhp Dyno Day. Your symptons are just like ours were.

Chuck


[Modified by Chuck Harmon, 12:09 AM 9/9/2002]
Reply
Old Sep 9, 2002 | 01:12 PM
  #3  
Maurice's Avatar
Maurice
Thread Starter
Safety Car
25 Year Member
Conversation Starter
All Eyes On Me
Liked
 
Joined: Jan 2001
Posts: 3,569
Likes: 1
From: Hawaii
Default Re: Top end performance question (Chuck Harmon)

A throttle bracket that has slipped at its rear left carb stud.
AH HA! It wasn't the throttle bracket that slipped, but the throttle cable wasn't set correctly, I think it was only opening about 1/2 way. I haven't had a chance to go and run it yet, but I definately think that is a HUGE part of the problem. I must resist the urge to go start it at 6am...I must resist...I must resist....Neighbors will not be happy... :D
Reply
Old Sep 9, 2002 | 01:15 PM
  #4  
Fevre's Avatar
Fevre
Race Director
15 Year Member
 
Joined: Mar 2001
Posts: 11,322
Likes: 1
From: Living in the Hartland
Default Re: Top end performance question (Maurice)

A throttle bracket that has slipped at its rear left carb stud.

AH HA! It wasn't the throttle bracket that slipped, but the throttle cable wasn't set correctly, I think it was only opening about 1/2 way. I haven't had a chance to go and run it yet, but I definately think that is a HUGE part of the problem. I must resist the urge to go start it at 6am...I must resist...I must resist....Neighbors will not be happy... :D
Same thing on my small block, the bracket has slipped. Not sure what it cost me at the track but sure it did not help.
Reply
Old Sep 9, 2002 | 04:07 PM
  #5  
Maurice's Avatar
Maurice
Thread Starter
Safety Car
25 Year Member
Conversation Starter
All Eyes On Me
Liked
 
Joined: Jan 2001
Posts: 3,569
Likes: 1
From: Hawaii
Default Re: Top end performance question (Fevre)

Well, I just got back from my test drive. Definately a HUGE improvement, I now have the top end acceleration I was missing, also picked up quite a bit lower end power that wasn't there before but knew that I should have. I am happy again.
Reply
Old Sep 9, 2002 | 04:09 PM
  #6  
Fevre's Avatar
Fevre
Race Director
15 Year Member
 
Joined: Mar 2001
Posts: 11,322
Likes: 1
From: Living in the Hartland
Default Re: Top end performance question (Maurice)

:cheers:

My carb was so out of tune I am not sure what I picked up but I know it runs like a champ now and opens fully.
Reply
Old Sep 9, 2002 | 04:42 PM
  #7  
Chuck Harmon's Avatar
Chuck Harmon
Melting Slicks
25 Year Member
Conversation Starter
All Eyes On Me
 
Joined: Apr 2000
Posts: 3,286
Likes: 8
From: San Jose California
Default Re: Top end performance question (Maurice)

:cheers:

Chuck
Reply
Old Sep 10, 2002 | 12:53 AM
  #8  
Maurice's Avatar
Maurice
Thread Starter
Safety Car
25 Year Member
Conversation Starter
All Eyes On Me
Liked
 
Joined: Jan 2001
Posts: 3,569
Likes: 1
From: Hawaii
Default Re: Top end performance question (Chuck Harmon)

Thanks for the tip on where to look.

If you want to see a blurry 1/4 mile video that has my car in it for a second or two, here ya go. http://home.hawaii.rr.com/sswim/movies/Z06-69-1.wmv Details on the race: I lost, yes after that lead I lost, that is the no top end power I was talking about. I ran a 13.8 at 95, the Z06 ran a horrible 13.4 at 110, he usually runs 12.9s but our track was very slick this weekend.
Reply

Get notified of new replies

To Top end performance question

Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

 Michael S. Palmer
story-1

2027 Corvette vs The World: Every Model vs Closest Competitor

 Joe Kucinski
story-2

10 Most Common Corvette Problems of the Last 20 Years!

 Joe Kucinski
story-3

5 MOST and 5 LEAST Popular Corvette Model Years in History!

 Joe Kucinski
story-4

2027 Corvette Buyer's Guide: Everything You Need to Know!

 Joe Kucinski
story-5

10 Things C8 Corvette Owners Hate (But Won't Tell You)

 Joe Kucinski
story-6

10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!

 Brett Foote
story-7

Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)

 Joe Kucinski
story-8

Grand Sport & Grand Sport X Launch Alongside All-New 535hp LS6 V8!

 Michael S. Palmer
story-9

5 Reasons Bad Drivers Crash & 5 Ways to Avoid a Costly Mistake!

 Joe Kucinski




All times are GMT -4. The time now is 04:28 AM.

story-0
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE
story-1
2027 Corvette vs The World: Every Model vs Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-20 17:58:41


VIEW MORE
story-2
10 Most Common Corvette Problems of the Last 20 Years!

Slideshow: 10 major Corvette problems from the last 20 years.

By Joe Kucinski | 2026-04-14 16:37:05


VIEW MORE
story-3
5 MOST and 5 LEAST Popular Corvette Model Years in History!

Slideshow: 5 most and least popular Corvette model years.

By Joe Kucinski | 2026-04-08 13:25:01


VIEW MORE
story-4
2027 Corvette Buyer's Guide: Everything You Need to Know!

Slideshow: 2027 Corvette buyer's guide

By Joe Kucinski | 2026-04-17 16:41:08


VIEW MORE
story-5
10 Things C8 Corvette Owners Hate (But Won't Tell You)

Slideshow: 10 things C8 Corvette owners hate, but won't tell you.

By Joe Kucinski | 2026-04-01 18:36:07


VIEW MORE
story-6
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!

Slideshow: Should you add one of these incredible Corvettes to your garage?

By Brett Foote | 2026-04-01 18:14:05


VIEW MORE
story-7
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)

Slideshow: Every Corvette Grand Sport explained

By Joe Kucinski | 2026-03-26 07:13:44


VIEW MORE
story-8
Grand Sport & Grand Sport X Launch Alongside All-New 535hp LS6 V8!

Slideshow: Breaking down the 2027 Grand Sport, Grand Sport X, Stingray, and LS6 V8.

By Michael S. Palmer | 2026-03-26 13:48:45


VIEW MORE
story-9
5 Reasons Bad Drivers Crash & 5 Ways to Avoid a Costly Mistake!

Slideshow: 5 reasons bad drivers crash sports cars & 5 ways to avoid a costly shame!

By Joe Kucinski | 2026-03-25 16:32:55


VIEW MORE