>From your description I am not sure what you are doing but if you are having pressure problems with the fuel system reconnect the vacuum hoses and try running the motor with the fuel cap loose (put it on 1/2 way) If for some reason the tank is running at a negative pressure then the fuel pump will have a hard time trying to get the fuel out of the tank against the vacuum. On the other hand if the tank is "swelling up" then you have a positive pressure problem. Again loosening the fuel cap should temporaraly "fix" this. If loosening the cap helps then you have to go over the vapor recovery system to see what is causing the problem. The fuel system for the engine doesn't work if there is any vapor in it, it is a totaly positive pressure, liquid system. The only place the vapors go is the vapor recovery system. If the fuel tank is at a negative pressure that would aggravate any tendency to cavitation before the fuel pump i.e. in the suction pick-up hose. Unless you are in extremly hot conditions if everything is functioning correctly you don't need any modifacations or insulation to the fuel tank. David Teitelbaum vin 10757 --- In dmcnews@xxxx, "therealdmcvegas" <DMCVegas@xxxx> wrote: > Took my car back out again today, and recreated the same > problem. This time, I had filled up the tank, and got the same > problem. So filling the tank with cool fuel fresh from the pump > doesn't solve the issue. Now, I've had this same problem since > before I installed the spring inside of the fuel pump pick-up > hose. The only difference is that since installing the spring, I'm > able to maintain accelleration. Although, I am al for excluding > both the spring, and the pick up hose all together to avoid these 6585 "X"