600 holley stumble off idle - Ford Muscle Forums : Ford Muscle Cars Tech Forum
FordMuscleForums.com is the premier Ford Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools
Old 08-28-2011, 04:06 PM   #1 (permalink)
Registered User
 
Join Date: Apr 2004
Location: Fort Myers, Fl
Posts: 286
Talking 600 holley stumble off idle

I have a 69 Torino with a stock 302 and a holley 600 that stumbles hard off idle. I just ordered on line a .035 squirter up from a .031 that it now has.

I need to also consider changing the orignial acc cam timing adjuster but I do not know which color to buy to help correct off idle stumble.

Any ideas ?

Thanks
Rodney Robbins
__________________
Rod and Alica
63.5 Galaxie 3 pedals
69 Torino Convertible
rod123 is offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 08-28-2011, 06:26 PM   #2 (permalink)
Registered User
 
Join Date: Jan 2008
Location: Seattle, WA area
Posts: 8,230
Re: 600 holley stumble off idle

First things first - did it do this before? Is it a new carb? If you push down on the accelerator pump arm, does fuel squirt hard on both primaries - and for the full travel of the arm? Have you set the arm preload properly first? Was the carb adjusted for proper idle mix first? Usually a 'hard' stumble on anything reasonably stock to moderately modded is a malfunction rather than gross mis-adjustment.

David
__________________
-=≡ If it was easy everyone would do it ≡=-
PSIG is offline   Reply With Quote Quick reply to this message
Old 08-29-2011, 08:26 AM   #3 (permalink)
Registered User
 
Join Date: Sep 2010
Location: Sedalia, Mo.
Posts: 163
Re: 600 holley stumble off idle

I'm experiencing this same problem on my 351C. I have a 600 DP (4776-4) on it with a single plane Intake. I'm thinking I need to increase the squirter size as well. The rear squirter is larger than the front so I swapped them and it improved some. The primary was a .028 and the rear is a .032.

I got disgusted...so I borrowed an Edelbrock carb from a buddy just to make sure I had a carb problem.. Thing runs awesome with the Edelbrock, but I have to give it back at some point, and I'd really like to use my Holley if I can.

I watched a YouTube video, and they suggested to increase the Squirter 3 sizes at a time. And I do have it adjusted correctly as far as I can tell (according to what I've read/watched).
__________________
66 Fairlane 500 XL (351C/Toploader)
49 Ford Club Coupe (8BA Flathead V-8)
DeeCees66 is offline   Reply With Quote Quick reply to this message
Old 08-29-2011, 09:53 AM   #4 (permalink)
Registered User
 
Join Date: Jan 2008
Location: Seattle, WA area
Posts: 8,230
Re: 600 holley stumble off idle

I know this seems redundant and a pain, but absolutely needs to be done right before making changes. First, be sure your ignition timing is correctly set (the primary word there is correctly). Anything done half-assed here will affect everything else as you go. Don't short-cut.

Then, follow a good basic setup guide, like this one. Be sure to read the link about vacuum gauges. When you've done that, read some other tips on basic adjustments here. Just gloss the whole thing a couple times to get the high-points and apply them.

Now - how does it run? Pretty dang good I'll bet. Where does it need more tuning? By this point the answers should be pretty obvious and fairly minor. Also, don't assume you need more when you need less or the same for a different period of time. For example, a stumble with a large-port and open manifold may not need more accelerator pump fuel flow, but rather the same flow over a longer period of time to let the engine 'catch-up' before the extra fuel is gone.

Enjoy the process, and post how it changes after following the basic tuning setup, and what you think it needs after that.

David
__________________
-=≡ If it was easy everyone would do it ≡=-
PSIG is offline   Reply With Quote Quick reply to this message
Old 08-29-2011, 03:29 PM   #5 (permalink)
Registered User
 
Join Date: Apr 2004
Location: Fort Myers, Fl
Posts: 286
Re: 600 holley stumble off idle

WOW so very good tips.
My carb is about one year old and when it was a new carb it did not have this stumble. I let it set a little too long so I had to take the bowls off and clean them. I installed a new pump diaphram and cleaned the sqirter nozzles. The flow from the squirters seem fine but I am not a carb guy.

So i ordered the .035 squirter and will look at the setup directions you guys pointed to.

Thanks for the help, I am sure I will learn a little about Holley by asking questions and getting my hands deep into it.......
__________________
Rod and Alica
63.5 Galaxie 3 pedals
69 Torino Convertible
rod123 is offline   Reply With Quote Quick reply to this message
Old 09-01-2011, 08:39 PM   #6 (permalink)
Subscriber
 
Join Date: Mar 2010
Posts: 578
Re: 600 holley stumble off idle

Quote:
Originally Posted by rod123 View Post
WOW so very good tips.
My carb is about one year old and when it was a new carb it did not have this stumble. I let it set a little too long so I had to take the bowls off and clean them. I installed a new pump diaphram and cleaned the sqirter nozzles. The flow from the squirters seem fine but I am not a carb guy.

So i ordered the .035 squirter and will look at the setup directions you guys pointed to.

Thanks for the help, I am sure I will learn a little about Holley by asking questions and getting my hands deep into it.......
Holley has a good book on it's carbs and it sounds like ACC pump timing off the ACC Cam. Make sure everything else is right first. and only change one thing at a time.
dacofaII is offline   Reply With Quote Quick reply to this message
Old 09-02-2011, 04:54 AM   #7 (permalink)
Subscriber
 
Join Date: Jan 2004
Location: Omaha, NE
Posts: 2,917
Re: 600 holley stumble off idle

Make sure the umbrella seal above the accelerator pump is good, if you didn't replace it, take it back apart and replace it now, then adjust the arm per Holley specs. It should move the second your linkage moves

Also, make sure the check ball, actually bullet shaped, is in place under your squirter.

If the car didnt stumble before the accel pump change, it should not require any change in design, it has to be something you did or you missed.
__________________

70 Sportsroof, 427 FE/489 cid, TKO-600, 31 spline 4.10, A/C. modified Mass-flo EFI/reprogrammed A9L/CnC ported Victor.
My427stang is offline   Reply With Quote Quick reply to this message
Old 09-08-2011, 12:37 AM   #8 (permalink)
Subscriber
 
Join Date: Jan 2001
Location: Texas
Posts: 2,216
Re: 600 holley stumble off idle

Try the pink cams and 31 squirters front and back. Run the primary pump cam in the #2 hole and the linkage a little loose. Secondary pump cam in the #1 hole and linkage according to the book.
__________________
1965 289 mustang fastback
Hottarod is offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Ford Muscle Forums : Ford Muscle Cars Tech Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Off Idle stumble Velocity111 Galaxie Pages 12 07-14-2011 05:39 PM
Holley Off Idle Stumble Fixed: F15Falcon All Ford Techboard 32 03-29-2010 09:12 AM
5.0 stumble at idle machwone All Ford Techboard 2 09-17-2009 10:35 PM
Intermittent stumble & die at idle rnourse All Ford Techboard 3 10-01-2004 04:46 PM
Off idle stumble / 95 Cougar 4.6 BUDMANRACING Late Model EFI Techboard 0 09-25-2002 08:21 PM


All times are GMT -7. The time now is 12:30 PM.



Powered by vBulletin® Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Friendly URLs by vBSEO 3.6.0
 

Garage Plus vBulletin Plugins by Drive Thru Online, Inc.