Results 1 to 8 of 8

Thread: 604 stumble

  1. #1

    Default 604 stumble

    I have a terrible stumble in the center of the corner when I pick up the fuel. It does it whether I roll on or hammer it. I took the carb to my guy and he ran it on the dyno and replaced gaskets and accelerator pumps. Still didn't fix it. Doesn't start happening till about 6 laps in the race. Doesn't do it in hot laps or qualifying. Any ideas would help.

  2. #2
    Join Date
    Jul 2014
    Posts
    455

    Default

    What battery are you running? Is your MSD box grounded? And have you put a new cap on distributer? Also could be a fuel starvation issue change fuel filter? It could be several things. That can cause that

  3. #3
    Join Date
    Jun 2007
    Posts
    3,123

    Default

    We once had the exact same problem and root cause was lack of fuel pressure. Got a quality pump and it fixed the problem.

  4. #4

    Default

    16v battery that always takes a good charge but I know that doesn't always mean anything. New fuel filter when I got carb "fixed"... I have raced this car with all the same parts last season and this season. Just started doing this the past 2 races... I am gonna check all my grounds and switch connections. Just seems like a fuel issue to me.

  5. #5
    Join Date
    May 2007
    Posts
    1,395

    Default

    Pump is what I'd guess as well

  6. #6
    Join Date
    Jul 2014
    Posts
    455

    Default

    We where having any issue about 10 consecutive laps in. The car would stumble coming off. Our fuel pressure was good from what I could tell on the gauge while racing. We went back and watched fuel pressure on the gauge and it was getting down to 2psi during the race. Changed filter and haven't had a issue yet. We did have a distributor cap cause this same issue too.

  7. #7
    Join Date
    Jul 2014
    Posts
    399

    Default

    So you have to think, what is different throughout the night that causes problem.... only after 6+ laps. Engine temperature? Fuel pressure? What is it early and when problem begins? Vapor lock if you are not running a return line system? When was the last time you replace the regulator, or at minimum the diaphragm inside? HTH

  8. #8
    Join Date
    Apr 2015
    Posts
    234

    Default

    I was getting ready to ask same ? Do u have a return line ive noticed that some people are not running one and this is not a thing i still to this day never understood why people would want to dead head all that fuel there some people dont realize how low the boiling point of fuel is i yhink its in between like 110 an 120 degrees which is very easy to get to under the hood with a return the fuel is constantly flowing which keeps it cooler

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

All times are GMT -5. The time now is 07:00 AM.


Powered by vBulletin® Version 4.2.0
Copyright © 2024 vBulletin Solutions, Inc. All rights reserved.