My 1974 Roadster was running hot in the 230*+- range. Not over heating however. Highway driving did not cool her down but increased temp. at high speeds. This is a stock LS4 454 with Rochester four barrel and 9:1 compression.
To the point, after checking the little things and flushing the radiator, the problem was fixed this way.
1) Rebuilt Carb. done by expert.
2)Retime engine that was retarded due to bad carburetor.
The timing can be the key! Make sure your engine is running at GM specs. Good luck!
Joel Adams
C3VR Lifetime Member #56
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"