i have an 86 z28. i have a problem with the cooling. with my fan always on the car sits around 230F and when im running down the highway it somtimes get to 260F and when i slow down goes to around 230 to 240. radiator is only 7 or 8 months old water pump about a year. all hoses are new 160F. high flow stat.

well since it gets hotter when you are driving I bet your air dam is missing or pretty destroyed. look under the car and the base of the rad core support. is there a black plastic wall sticking down about 6 inches? if not get one. Hawks Third gen sells them for 25 bucks or you could order one through your local dealership.

thats a start. just remember GM designed these to run HOT as in the factory fan switch is around 225-230. and the air dam is needed for staying cool while driving.

theres no air dam there. and the my fan is rigged to stay on. couse i cant find the switch on the block that turns the fan on

Do you have a dual fan?

Anyhow, if the fan is always running, that wouldn't hurt and should help keep your car at a lower temp.

Get that lower air dam put back in. Check to make sure you're running with full oil, and your coolant levels are topped off.

Also, you can use a "water wetter" additive product in your coolant which will help drop the temp too. But it's not a long term solution.