I run mine at 190* as it's more efficient there. Keeps the plugs cleaner and better fuel mileage (its' a 408 so I need all the fuel mileage I can get). I'd check with an infrared temp gun as SIX225 recommended. I installed an expensive Autometer temp gauge and right off the bat it was off 15 degrees. I never trust gauges until I verify them with my temp gun
I know this isn't related to your question but something isn't right cause that cam should idle decent at 700-750 in neutral. Did you recurve the distributor to give it more initial timing? If not you need to
