Help, I have a A1 itb chassis with a problem that is stumping us. The car is equiped with msd, fixed distributer with and advance control, cockpit mounted, rev limiter, 10 gallon cell, two low pressure pumps filling sump to high pressure pump. The vehicle runs fine until everything gets hot, 30 minutes into the race then its like an on and off switch, high rpms 5-7 engine shuts off for a second or two then comes right back on. This goes on for the duration of the race, in the pits it can not be duplicated without a load on the motor or electrics I think. Replaced both low pressure pumps, coil, moved exhaust to prevent vapor locking the fuel system, no low fuel pressure, MSD said that our unit either works or will not, no itermittent problems. Where do I look next, oh replaced alternator and wires to it. Help.