engine is running too rich,Help! - Team Camaro Tech
Troubleshooting Diagnosing problems done here.

LinkBack Thread Tools Display Modes
post #1 of 4 (permalink) Old Apr 26th, 02, 03:27 PM Thread Starter
Join Date: Jul 2001
Location: tucson,az
Posts: 18
well, here's my problem my holley 750 cfm carb it's allway making my engine run really rich,my exhaust i vary smokey and when i punch the gas quilkly the carb pops. my engine is newly rebuilt it has a comp cam magnum 270H series cam with a 224 dagee duration and a .470 lift,edelbrock rpm intake manifold,G.M. hp heads with 2.20 intake valves and 1.60 exhaust valves,holley 750cfm carb, my compression is 9.73:1,

at first i thought i had a blown power valve so i replaced it,no improvement so i put a power valve plug in my carb still no improvement, i played with the mixture screws no changes. i put some new spark pluges in and readjusted my roller rocker arms, because i looked at my vacuum gauge is read around 15 hg but was vary bouncy wich indacates sticking valves or ignition miss,i reset my ignition timing to 12 drgrees. could my carb jetting be too big?

any suggestions would would be greatly appreciated.
72'camaroguy is offline  
Sponsored Links
post #2 of 4 (permalink) Old Apr 26th, 02, 03:39 PM
Senior Tech
Join Date: Aug 2000
Location: DULUTH, GA.
Posts: 917
If you are running anything less than 360 cubes and/or less than 6000RPMs....yes, it's too big.

If you do not have alot of experience with carbs, my recommendation is to go for a simpler and easier to tune carb. Go for a Carter or Edelbrock AFB. And yes, I would go for a 600, but the 750 will go on with jet/rod changes.

ConceptOne Pulleys and Brackets
Techical forum/links at www.inccn.net/techforum.htm
HOTRODSRJ is offline  
post #3 of 4 (permalink) Old Apr 26th, 02, 04:02 PM
Join Date: Sep 1998
Posts: 470
I think what HOTROD was trying to say is that not only is the jetting too big, but the carb is too big for that motor. You really need to switch to a 600 or 650 carb.

If you keep running that carb, you will probably need to drop about 10 jet sizes to get any where near the right settings.

A bouncy vacuum reading usually indicates a vacuum leak or a miss. Most often, it is a vacuum leak, but in this case I'd say the motor is probably loading up on fuel real quick and causing the miss. Have you checked your new plugs?

Also, is this a vacuum secondary carb?

Best of luck,
Bill C.

Bill C.
Colorado Springs, CO

68 Camaro... someday!
71 Chevelle SS
70 Nova
BC is offline  
post #4 of 4 (permalink) Old May 1st, 02, 03:34 AM
Senior Tech
Join Date: Mar 2000
Location: Dtown PA
Posts: 820
i dont think its too large,

I have a 750 Vacuume secondary on my 67's 327 with a Comp280xe cam , th350 9.5:1 and a 3K stall, it works great. i'm running 68 jets with a 36 squirter, it runs great. but I gues it depends on the engine setup. the 650 I had on it was starving the car.

Chris's 67 RS/SS,can be seen at http://www.67rs.com
check out another site once in a while! http://www.fbodyconnection.com
Chris Edwards is offline  
Sponsored Links

Quick Reply

Register Now

In order to be able to post messages on the Team Camaro Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address.
NOTE we receive a lot of registrations with bad email addresses. IF you do not receive your confirmation email you will not be able to post. contact support and we will try and help.
Be sure you enter a valid email address and check your spam folder as well.

Email Address:


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome