I need help from you Cobra gurus
Here is the problem: After running about an hour of so, the car starts to run like sh**.
It spits and coughs, and doesn't want to rev. The fuel filter looks empty. After I turn it off for about 15 minutes everything is fine.
Pertinant details: 351 W, mechanical fuel pump, in-line filter upstream of the pump. All this in a Johnspeed Cobra.
Looking at the system, I am not surprised. The filler cap seals tight. There is a breather hose from the top of the tank back into the filler neck, for burping during filling I suppose, but that still leaves it a closed system.
It seems to be worse (happen sooner) with a full tank. However, when it is acting bad, and I open the filler cap, it does not fix the problem. Even if I ride around and slosh the tak with the filler cap open.
Also, the burp line does not seem to be working. I have to fill real slow.
Here is my plan: I will pull off the burp line and make sure it is free of obstructions. I will splice into it near the filler neck, and run into a check valve and out into open air. I am suspecting that once it is pulling a vacuum, it starves the pump, and it will not re-prime until the car is off for a while. I don't know.
So, my question is, do you think this will work? Where can I get a check valve that will handle gasoline vapors? Could it be something else? Heat related or something? Should I add an electric fuel pump at the tank with a switch? I am open to suggestions, but there is nothing worse than being stopped at a red light when the fan beside you says "lets hear it!" and you rev it and it sounds like sh**. And oh yeah, getting stranded on the side of the road ain't too cool either.