Car bogs in the corners, road race.

[Rokker]

I had my 65 Chevelle at the track yesterday. The road race cours is about 1 minute 10 seconds long with the best cars reaching 120mph and going around 75-80 in most of the turns.

Overall, being my first track day event, I totally enjoyed it. The sc&c suspension system held up great and I would have passed a few cars on 15" tires if it hadn't been for one Big issue.

When pushing the car in the turns it starts to bog and stutter when going in to the pedal, it keeps stuttering for a while down the straight and then looses all power. If I let go and drive slow it cures and works fine until the next turn and then it starts again. I've never noticed this when pushing it on the streets, but now that I now I notice the same thing happen there. Also when doubt donuts it will suddenly loose power.
I have my suspicions on what is wrong but would love to hear you comments! This will not happen that much in the first laps, but when starting to push the car it becomes a big problem.

Combo:
Stock fuel tank and Lines
Holley red pump in the engine bay
Prosystems double pumper, 1000 hp
ZZ502 with cam and 11,2:1 cr.

I tried:
Fuel bowls 95% full glass - same problem
Fuel bowls just under glass - same problem
Front fuel bowl at 40% and rear under the glass - same problem
Backing off the timing alot - same problem, ran like a dog.

What do you believe is happening ?
I know my fuel system is not the best, but has been working fine on the street so haven't messed with it.

[Rokker]

I forgot to add, I run a HEI with 90 degrees plug wires and 5-6 of them is touching the headers. I am wondering if I might be getting a bad spark at some of the plugs as the heat rises and the rubber get's softer and might be bringing the wires close enough to create a spark between wires and manifold ?

[wmhjr]

My guess? Non-sumped tank and losing fuel pressure when you add lateral force. What were your fuel levels when this happened? Stock pickup and sending unit?

The one constant you have every time this starts is that the car is in a relatively heavy G turn. So what changes in that situation? Fuel displaced to the outside on a flat tank with stock pickups. Pump starts getting air as the fuel moves away from the pickup. Initially there's enough in the bowls to run the motor, but under heavy throttle that will burn quick. Keep on the throttle and even after the pump stops cavitating, it can't catch up initially. Slow down in the straight, backing off the throttle allows the pump to get some fuel back in those bowls.

Somebody else could have a completely different opinion.

[Vegas69]

I agree, always race with as much fuel as possible. You dropped your floats so that shouldn't be the problem. I would reccomend a road race rear float and jet extensions, but I highly doubt that is your problem, especially the first time out.

[PSV]

I may be way off base but I think your pump needs to be in the rear of the car by the fuel tank as its designed to push fuel. You may be usng more fuel than the pump can replace with it it the engine compartment and only a short run to the carb.

[NOT A TA]

Originally Posted by PSV

I may be way off base but I think your pump needs to be in the rear of the car by the fuel tank as its designed to push fuel. You may be usng more fuel than the pump can replace with it it the engine compartment and only a short run to the carb.

^^^ this