Got the new motor fired up finally. Put the timing light on it and it will only run at "47" degrees and above. If I try to retard it, it will run like crap and wont start. It starts pretty easy and isn't getting hot at "47" degrees. Tried 2 different lights with same result. Any ideas would help a lot. Thanks. It's a sbc 418 with brodix aluminum heads and msd ignition