View Full Version : Circle track dirt car problem

07-12-2010, 05:13 PM
I have a 355 with a holley 4412. When I get in the throttle coming off the turns, the engine bogs slightly and then comes back. This is all the way down the straights. Fine in the corners because of feathering. I have changed everything electrical in the car including complete wiring of the entire car. There is not an electrical component that I haven't changed. So now i am leaning on fuel delivery. I tried a Rochester carb and had the same problem. I have a racing fuel pump (can't tell ya the name right now). Any ideas where to go from here???

07-12-2010, 11:59 PM
Is your fuel pump good or is 100 years old? Also the fact that it does it with both carbs makes ya think it isn't geting enough fuel to the carb for some reason. Restricted fuel line faulty pump etc. I assume the float level is correct.

If you are allowed maybe put a fuel pressure gauge with an isolator , so you can watch the fuel pressure while you are running it.That would tell you if it was the carb or the fuel system.

07-13-2010, 12:08 AM
I've always heard that 9/10ths of fuel problems, are in the ignition.

07-13-2010, 05:53 AM
How old is the fuel cell foam ? Could be chunks of deteriorated cell foam blocking the inlet .

07-13-2010, 04:50 PM
Well, you guys are all on the same thought pattern I am in regards to fuel pressure. Fuel pump is quite old. I didn't quite understand the post that said "most fuel problems is the ignition!!!!". The foam is as old as the fuel cell itself which is as old as the car and that is at least 10-12 years or more. I am going to start unhooking lines tomorrow and watch for flow. I also wonder about the fuel cap and the bleed valve. I will let ya know if I find it. Bad thing is, I never know until I get to the track and I loose money every time because of it.

07-13-2010, 05:08 PM
Fuel cell foam should be replaced every couple years according to the website below.


07-14-2010, 05:21 AM
It was a joke, and a lousy joke at that, and I apologize.

07-14-2010, 07:00 AM
That old of foam will require replacement !! You'll need to purge the COMPLETE fuel system. Remove the cell foam, the cell and clean, and blow out all your lines, filter/s, pickup screen, etc.
Even IF that does not fix the original issue, IT NEEDS TO BE DONE.