I have a 1973 Chevelle Wagon. It has a 350 with a small voodo cam. Up untill last week all was well ran 190 t0 200 deg with the a/c on. It has a brand new alu radiator new water pump and new high flow thermostat. Dual electric fans with a thermostatic switch that turns them on at 195. The timing is 15deg at idle and total of 30 deg at 1500 to 2000. It started to run hot about 220 at idle and climbs up at 45 to 55 mph. It will cool down a little if you rev it at idle. but only down to 220. A/c on it just keeps climbing. I have taken the electric fans off and put the stock clutch fan back on, no change. Took the after market rad out and put stock one in no change. Please some one help. There is no bubbling in the radiator so I dont think it is a head gasket. And Ive also tried two gauges just to eliminate that.

I would not be afraid to run more advance unless it pings. Bring the car up to temp with the rad cap off and see if there is circulation when the t-stat opens. the aluminum rad is the better one. The t-stat could be sticking or there is the out side chance that the impeller has sheared off of the shaft and is not pushing coolant (this happened to me). Water wetter or other addatives also help. My electric fans have an over ride switch that keep the fans on all the time when the temps run high also, my 454 runs cool in stop and go traffic but the ac does up the temps.

Hello,x2 check thermostat and water pump. are you running a fan shroud and are your fans mounted correctly in the shroud. also is your trans cooler in the radiator or do you run a seperate one. not having the hot trans fluid going thru the radiator makes it run cooler. when in traffic there is no where for the hot air that accumulates under the hood to go. having a SS type hood or cowl type will help that air escape out from under the hood when in traffic. i have a 16 inch puller and a smaller pusher fan mounted in front to help in traffic,seems to help alot. my puller fan is switched always on and the pusher fan is used when needed. make sure you have a alternator that is of higher amperage,hope you get things cooled off.

Ive run across this before. The culprit from my experience was the water pump. With all the upgrades on the engine ant timing you'll need a water pump that can cycle the water quicker for ease of cooling.

Thanks for all the help. Finally found it was the t-stat, it was a brand new mr.gasket high flow unit. I have had a string of bad luck with mr.gasket stuff. Replaced it with a stock 160 and she ran 180 all last evening and it was 87deg hear with the a/c on. Now I just have to switch rads back and put the electric fans back in. Thanks again, you guys are great no matter what other people say about ya.

We've heard the same about you:D

you by chance running "power pulley's" (smaller diameter crank pulley)

from my experience with them, I put the stock crank pulley back on and my overheating issues went away (so did my charging issues)

No im running regular stock pulleys.