Have a 540 BBC 700hp in my custom truck. Alum. high perf. radiator, 24 lb. rad. cap, 160 deg. thermostat (two 1/4" & two 1/8" holes), no water pump bypass line, Fast fuel injection. running straight water with Prestone Super Anti Rust and a little antifreeze (checks to +20 degrees). Can't cool it even long enough to get it out on the highway to see if it will cool at high speed. Need all the help I can get, so please don't hesitate to give any suggestion no matter how trivial you may think it is. Thanks

This is the first time I have posted any thing her so excuse me if I make a mistake. I'm not sure I even know how to find any answers you may suggest.