this may be a no brainer. If idle is low, then water pump is moving too slowly.
Also, is it a quality water pump. Also, at low idle, fan moves slowly. So up the idle
some and see what happens. I have my car idling at 1400. I slip it into neutral
at stop lights. Also, bottom rad hose is to be bigger than upper hose.
« Last Edit: June 20, 2017 - 11:15:04 pm by cudabob496 »
72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.
1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"