What is the correct pressure thermostat for a 1966 skylark 300cu in with a/c. The car had a 6# cap and was always "marking it's spot" whenever it was parked. Autozone said trhe correct cap was a 14# cap which I just put on. No more overflow, but I'm worried what 14#'s of pressure will do to a 42 year old, stock radiator and heater core. Any input will be appreciated. This car was converted to R134 and cools down great, better than my 07 F150. Thanks
GM book shows 64-66 all except 400 engine use a 180 deg. t'stat & 64-69 all use an RC-15, 15lb. radiator pressure cap.
Just because you have a 14# cap doesn't mean the system will reach 14#. But to be perfectly blunt, if your radiator/hoses/gaskets can't handle 14# then it's time for a recore or replacement. -Bob C.
