bog/stumble - Team Camaro Tech
Engine General Engine Discussion.

LinkBack Thread Tools Display Modes
post #1 of 4 (permalink) Old Nov 22nd, 05, 10:37 PM Thread Starter
Senior Tech
Join Date: Mar 2001
Location: Niceville Fl
Posts: 1,070

I have noticed over the last few day that my engine has devloped a slight hesitation if you stab it into WOT but if you ease into it it takes off like crazy. Also if i just floor it it will bog and sometimes give a little backfire throught the exhaust but then takes off like crazy. I was thinking that it might be a timing issue because sometims when I shut it off it desials alittle bit.. IT just started doing this on its own but this is a new motor with about 1000 miles on it now and it is just starting to get broke in.. Any Ideas?

69 Camaro RS, 383ci,10.5-1 AFR 195's ported, Comp 286HR, 4340 forged Crank & Rods, JE Pistons, RPM Airgap, Holley 750 HP carb, 350 turbo w/ shift kit, 3000 Coan, Be cool, caltracs,12bolt 355 eaton posi..Best E.T. 12.22 @ 112

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
69CamaroRacer is offline  
Sponsored Links
post #2 of 4 (permalink) Old Nov 23rd, 05, 05:46 AM
Senior Tech
Join Date: Oct 2005
Location: Rhode Island
Posts: 1,356
Re: bog/stumble

Your sig says you got a Holley 750, so my main suspect would be the accelerator pump circuit. Holley carbs are easy to tweak the pump shot. Look down carb and work the throttle. You should IMMEDIATELY see two strong shots of gas, one into each venturi.

There are typically two check valves, one is a silver ball under the pump diaphragm (held in place by peened-over tabs) and the other looks like a small upside-down rocket located under the pump squirter (removed with a philips driver). Make sure both of those are good. A piece of dirt anywhere in the accelerator pump circuit will cause your symptoms. Also check the pump diaphragm and linkage.

Of course, make sure your tune is good too.

Dave F. in Rhode Island
'68 Camaro SS Accel DFI 454 (SOLD - I'm a boring Corvette owner now)
Bought my first big-block Chevy in 1970
Chevy-SS is offline  
post #3 of 4 (permalink) Old Nov 23rd, 05, 06:19 AM
Super Moderator
Bess-68's rule
Everett#2390's Avatar
Join Date: Sep 2000
Location: Va Beach VA
Posts: 31,750
Re: bog/stumble

When you remove the squirter to check the ball, replace the screw with Holley's hollow screw, both pri & sec. squirters. Allows less fuel flow restriction.

I would advance initial timing and turn down curb idle.

Give a man a rescued dog for the health of both their souls. May 2017 ROTM Winner - Thank you!
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
CUBS - 2016 World Series Champions - Thank you, Joe Madden Ö enjoy your next chapter.
Everett#2390 is offline  
post #4 of 4 (permalink) Old Nov 23rd, 05, 02:28 PM
Join Date: Jul 2005
Posts: 43
Re: bog/stumble

I had the same issues with my brand new 383 a few weeks back. I know that my carb needs to be tuned so i was waiting until the motor had 1000 miles on it or so to have some shop put it on the dyno and tune it. Anyway a couple weeks back i changed the timing slightly about 6 degrees initial and now it's like night and day. You may want to check the timing and try tweaking it but definetely have the carb tuned if it hasnt already been tuned.
bfunky 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