CorvetteForum - Chevrolet Corvette Forum Discussion

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

Back Fire

Thread Tools
 
Search this Thread
 
Old Jul 9, 2011 | 11:04 AM
Share
  #1  
Cobfree's Avatar
Cobfree
Thread Starter
Racer
15 Year Member
 
Joined: Feb 2010
Posts: 261
Likes: 0
From: St. Louis Missouri
Default Back Fire
I had my original 327 rebuilt this past winter includeing the carb. Recently I am getting alot of back fire when the engine in hot and rev. from 600rpms. Also a little hard to start and at 4,500+ RPMs start to fall a little. She runs great until it gets hot (190).
Thoughts!
The carb is a rebuilt Carter.
Reply
0
Old Jul 9, 2011 | 05:40 PM
Share
  #2  
baxsom's Avatar
baxsom
Le Mans Master
15 Year Member
Liked
Loved
Top Answer: 1
 
Joined: Jun 2008
Posts: 5,284
Likes: 235
From: Rockledge FL
Default
timing?
Reply
0
Old Jul 10, 2011 | 09:49 PM
Share
  #3  
Phlash's Avatar
Phlash
Racer
20 Year Member
 
Joined: Oct 2001
Posts: 274
Likes: 2
From: Pampa Tx
Default
Agree! First check timing. It sounds like it is too far advanced. Could also be dwell is not set right.
Reply
0
Old Jul 10, 2011 | 10:59 PM
Share
  #4  
hwcoop's Avatar
hwcoop
Melting Slicks
15 Year Member
 
Joined: Apr 2006
Posts: 2,084
Likes: 14
From: Airdrie Alberta
Default
Or Lean condition caused by bad accelerator pump rubber
Reply
0
Old Jul 11, 2011 | 03:56 PM
Share
  #5  
Cobfree's Avatar
Cobfree
Thread Starter
Racer
15 Year Member
 
Joined: Feb 2010
Posts: 261
Likes: 0
From: St. Louis Missouri
Default
I will have to check the timing tonight
Reply
0
Old Jul 11, 2011 | 11:18 PM
Share
  #6  
73, Dark Blue 454's Avatar
73, Dark Blue 454
Melting Slicks
10 Year Member
 
Joined: Mar 2005
Posts: 2,838
Likes: 10
From: Austin TX
Default
95% of the time, backfire through the exhaust is lean-out as stated above. Backfire through the carb is usually a timing issue.

Look for a vacuum leak first. There are many places to look since seemingly the entire car runs on vucuum.
Reply
0
Old Jul 12, 2011 | 08:47 AM
Share
  #7  
Cobfree's Avatar
Cobfree
Thread Starter
Racer
15 Year Member
 
Joined: Feb 2010
Posts: 261
Likes: 0
From: St. Louis Missouri
Default
It does backfire through the carb. Vacuums are fun to find.
Reply
0
Old Jul 12, 2011 | 09:15 PM
Share
  #8  
glackore's Avatar
glackore
Pro
15 Year Member
Conversation Starter
All Eyes On Me
 
Joined: Dec 2006
Posts: 695
Likes: 5
From: tx
Default
Vacuum leaks can be found using some carb cleaner around the intake, carb, base plate, etc. The idle will go down when the juice finds the leak.
Reply
0
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

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

 Michael S. Palmer
story-1

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

 Joe Kucinski
story-2

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

 Joe Kucinski
story-3

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

 Verdad Gallardo
story-4

Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

 Joe Kucinski
story-5

Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

 Verdad Gallardo
story-6

Top 10 Corvettes Coming to Mecum Indy 2026!

 Brett Foote
story-7

Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

 Michael S. Palmer
story-8

10 Revolutionary 'Corvette Firsts' Most People Don't Know

 Joe Kucinski
story-9

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

 Michael S. Palmer
Old Jul 13, 2011 | 08:14 AM
Share
  #9  
Cobfree's Avatar
Cobfree
Thread Starter
Racer
15 Year Member
 
Joined: Feb 2010
Posts: 261
Likes: 0
From: St. Louis Missouri
Default
Great idea... Thanks
Reply
0
Old Jul 27, 2011 | 05:28 PM
Share
  #10  
Cobfree's Avatar
Cobfree
Thread Starter
Racer
15 Year Member
 
Joined: Feb 2010
Posts: 261
Likes: 0
From: St. Louis Missouri
Default
Your were correct, the timing was off! Thanks
Reply
0
Old Jul 27, 2011 | 11:23 PM
Share
  #11  
scottyp99's Avatar
scottyp99
Le Mans Master
15 Year Member
 
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
Default
Originally Posted by Cobfree
Your were correct, the timing was off! Thanks
C'mon, don't leave us hangin', how far off was it?


Scott
Reply
0
Old Jul 28, 2011 | 08:24 AM
Share
  #12  
Cobfree's Avatar
Cobfree
Thread Starter
Racer
15 Year Member
 
Joined: Feb 2010
Posts: 261
Likes: 0
From: St. Louis Missouri
Default
Don't know as I gave up and took it to the shop. Then leaving the shop the brakes went out. Joy of a 43 year old car. I will post the answer tonight when I pick it up.
Reply
0
Old Jul 28, 2011 | 01:01 PM
Share
  #13  
Easy Mike's Avatar
Easy Mike
Team Owner
Supporting Lifetime
20 Year Member
 
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
Default
Originally Posted by 73, Dark Blue 454
...Backfire through the carb is usually a timing issue...
And extremely impressive if you happen to be standing there and see the flash.

Reply
0
Old Jul 28, 2011 | 01:46 PM
Share
  #14  
Cobfree's Avatar
Cobfree
Thread Starter
Racer
15 Year Member
 
Joined: Feb 2010
Posts: 261
Likes: 0
From: St. Louis Missouri
Default
More like scared the %^&* out me as I had the air cleaner off.
Reply
0
Old Jul 28, 2011 | 02:11 PM
Share
  #15  
Easy Mike's Avatar
Easy Mike
Team Owner
Supporting Lifetime
20 Year Member
 
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
Default
Originally Posted by Cobfree
More like scared the %^&* out me as I had the air cleaner off.
Exactly. Been there, done that.

Reply
0

Get notified of new replies

To Back Fire

Back to Subforum
C3 Tech/Performance
View Next Unread
What is the best oil and weight for a 454?




Click for Advanced Search
Reply Closed Thread Share
Forum Jump
Trending Topics

All times are GMT -4. The time now is 07:51 AM.

story-0
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-1
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-2
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-3
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
story-4
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

Slideshow: Ranking the top 10 Corvette engines by torque output.

By Joe Kucinski | 2026-05-05 11:58:09


VIEW MORE
story-5
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

Slideshow: A Corvette pace car nearly matching IndyCar speeds sounds exaggerated, until you look at the numbers.

By Verdad Gallardo | 2026-05-04 20:03:36


VIEW MORE
story-6
Top 10 Corvettes Coming to Mecum Indy 2026!

Among a rather large group of them.

By Brett Foote | 2026-05-04 13:56:44


VIEW MORE
story-7
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

Slideshow: the top 10 things Corvette owners want in the C9 Corvette

By Michael S. Palmer | 2026-04-30 12:41:15


VIEW MORE
story-8
10 Revolutionary 'Corvette Firsts' Most People Don't Know

Slideshow: 10 Important Corvette 'firsts' that every fan should know.

By Joe Kucinski | 2026-04-29 17:02:16


VIEW MORE
story-9
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