car overheating

[stang13]

  I finally got my 70 challenger back on the road . I have installed an rebuilt 440 6 pk that has a stroker kit in it so I am putting out a lot of heat. the engine was rebuilt by a professional engine builder . it

runs strong and idles at about 900 rpms. Today it was about 80 degrees and I was on my was to a cruise . I stopped at a few traffic lights that were red and as I sat I watched the temp gauge rise into the hot zone . when I pilled into the lot I noticed a good not of antifreeze coming out of my overflow canister . I have a brand new aluminum radiator installed in it . I say I lost a few cups of antifreeze
 I let it cool and went home a different way with fewer lights with no overheating . any suggestions what I can do to prevent this I. The future. ?

[taxspeaker]

I think I would start with a couple of obvious, easy and cheap solutions:

1. Make sure it really is overheating-a lot of the aftermarket sending unit replacements I have found read high

2. With a fresh rebuild I wouldn't be surprised if you had some air pockets in the engine and hoses-very common and often a simple fix that fixes itself after a few refills.

3. Are you running a factory fan? I have seen lots of problems when not re-isntalling the factory shroud, or replacing the factory fan with an aftermarket fiberglass one or both.

Well thats a start-hope you get it, I'm sure by Sunday there will be a lot of suggestions

3.

[stang13]

I have about 100 miles on the car without no overheating issues. I reused the shroud but I n running a fiberglass blade

[Chryco Psycho]

Engines will run hotter for the first miles after a rebuild but as you say it stayed cool before , my first recommendation is a 18" Flex-A-Lite fan 6 blade & a clutch , this will pull a lot more air , the problem you are having is air flow when sitting still if it cools Ok when moving so making sure the shroud I sealed to the rad with a good fan should keep the temps down , I would recommend a 180* T stat not 195* as well