i got a b16 in my si and my temp be gettin superhot durin hot days. i got a autometer water temp and normally, my gauge be sittin around little under 210 degrees. when the weather gets hotter and im just daily drivin around, my shiet be risin up around 250-270 and up and my stock temp goes half way. my fan and thermostat all works fine.

is it because i still have the puny civic radiator? should i step up to the del sol one? i know my headgasket is fine, i dun see my any leaks and such. im usin prestone coolant, is there a coolant better then prestone?

any ideas?