Can anyone tell me about how to keep a 401 running cool. Here's my issue:
I have a '74 Matador X Coupe 401. The engine is a correct 1974 engine. I have had it apart twice. Both times, it wanted to run on the warm side at highway speeds. My Javelin 401 does not have this problem, but it does not have A/C either (yet), and the car is much lighter.
At a constant cruise at 70, with the A/C on, the temp gage will slowly, but surely climb. I never let it overheat, but I can see that it could overheat if I did not pay attention to it.
I have the following:
.040" overbore with Sealed Power replacement pistons, RPM Air Gap intake, Phenolic carb spacer, 3-row brand new radiator, factory AMC heavy-duty 7-blade flex fan and NOS brand new shroud. Brand new valves, springs, etc, along with Comp cams XE262H cam kit (nice cam).
Before I had it torn down this spring, I tried two thermostats - a 160 and 180. The 180 did better. I have another 160 in it now and will probably go back to the 180. I want to tow on the highway with this car, but I think it's not going to stay cool. Oh, I have one bottle of Water Wetter in the system now also.
Last summer, going to Cordova, it was the same way - if I cruise slower it does better, but I still have to watch it. Ideally I want to tow my Jav on an open car trailer to Cordova. I've towed locally with no problems, but the highway speeds get it heated up. Long idling in hot weather is similar also, but not real bad.
Any tips would be appreciated.
Bill Dettman
'74 Matador X 401, '70 Javelin BBG 401
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