Re: ford 390 big block over haeting at idle
Well 200 isn't too hot for safety, but I understand your frustration.
Assuming head gaskets aren't on backwards, which would always overheat, the only things are
1 - airflow / fan design
2 - water pump and and shaft speed
3 - bad radiator
4 - ignition timing set wrong (even if it looks right)
So, if you would take some pictures or give part numbers, here is some info
1 - Which fan did you use? Part number best, but if you have a good description that's good too. Flex fans aren't great
2 - What is the diameter of your water pump and crank pulley on the groove that holds the fan belt. The crank has to be bigger or at least equal to the fan
3 - Doesn't sound like a radiator, but, how are you bleeding the system, not wanting to offend, just some guys do odd things. I let them idle cap off / heater valve open until thermostat opens
4 - Have you ever checked if your balancer is correct? If it slipped or a bad pointer / balancer combo, it could be 6-8 degrees off, if timing then set to specs, it can drive a TON of heat
I will try to tell you what I think after you report back, but there isn't much inside that can make it idle slightly hot (not horrible but annoying I'll add) like that
One last comment, how are you measuring temperature?
70 Sportsroof, 427 FE/489 cid, TKO-600, 31 spline 4.10, A/C. modified Mass-flo EFI/reprogrammed A9L/CnC ported Victor.