im running a 89 k5 blazer 5.7l 350 v8 with a 700r4 trans 4x4 auto i broke my radiator in a recent rebuild of the top end and now i cant remeber what size went in it i kno it was bigger than the 19in the auto stores around here says it is and the cap has to hold more than 16lbs of pressure i am wondering what the ex specs are can anyone help me? i also have a trans cooler on it

 

Even larger capacity radiators usually only hold 16psi. Check on a 3/4 or 1 ton unit with trans and engine cooler. Higher GVW units also tend to be larger. If you have the old radiator still just use the measurements to match up