Project Deimos: An LS '65 Coupe Build: Engine no longer overheating!

[Papa]

My BPE 347 was the same way. When they dyno the engines, I think they just run plain water, not antifreeze in the engines. Mine sat a few months before installing it and filling with coolant. I had to drain it and flush multiple times to get all the crud out of the engine that I think was just rust from the block being wet with no coolant for so long.