Radiator Overflow

[Rev]

Could be a weak cap. I always put in about a 15 psi cap. I think it's always a good idea to install an overflow tank. You can get one at PepBoys for $15-20 and they are easy to install. The engine acts as a heat sink after turning it off. My temp guage always goes to H after shutting off while running at 180 F while driving. That's almost guaranteed to over pressure even a good cap. The overflow tank will of course capture the overflow and then let it get sucked back in as the engine cools down. The drag strips do require an overflow tank so as to try to keep fluids off the track.

Rev