Thermostat Opening Late?

[PlayingWithTBI]

Higher the temps the higher the tendency toward detonation.

I'd be more worried about Intake Air Temp than the T-Stat. Some ECMs have the capability to add an IAT sensor so it can reduce timing based on those temps to help prevent KCs.

 

[El Tigre]

Suit yourselves. I see little advantage to running temps as high as possible though.

 

[Schurkey]

The ideal situation is that the block is kept as hot as practical--195+, while keeping the intake manifold and cylinder head inlet ports as cool as practical. You get all the benefits of the high coolant temperature described in my previous post, while not overheating the air/fuel mixture leading to detonation.

GM spent a giant heaping pile of money "reverse cooling" the older LT engines trying to achieve "cool" cylinder heads and retain the "hot" engine block. Pontiac did the same thing decades earlier--the '55--'59 or '60 Pontiac engines were also "reverse cooled" except that Pontiac called it "Gusher Cooling". The openings in the cylinder heads for the water pump outlet was carried in production to the end of the Pontiac V-8. After '59 or '60, though, those passages were sealed with a core plug instead of the water pump outlet castings.

It's why you see plastic intake manifolds now instead of aluminum or iron. Plastic doesn't conduct heat as well as metal, aluminum in particular. They got rid of the exhaust crossover passage in the cylinder heads and intake manifold (there's no fuel in a "dry" intake manifold that needs added heat to vaporize.) Decades ago, GM and the others quit using under-hood air for the carb intake; Mom's '77 Nova has plastic ducting to pull in "ambient" air instead of hot underhood air. But "hot rodders" know better, I still see plenty of stupid open-element air filters on modern vehicles.

What I don't see the Major Manufacturers doing is spending money on thermal barrier coatings on the intake ports, combustion chambers, or on the exhaust ports. Maybe that doesn't work as well as the aftermarket coating industry would have us believe.