Eastwood High Temp Internal Exhaust Coating

Being that there is no "Stupid Newbie Question" topic I'll just post here in Misc. Currently rebuilding a 1985 Mercruiser 2.5L that was garage stored for years. There was a good bit of internal rust through out, including the cylinders which I had bored out +.030. Soaked everything I could in Evapo-Rust which worked much better than I anticipated. Right now the soaking the head intake and exhaust chambers and already done the manifold.

Now for the newbie question, would coating these internally (not the valves and seats of course) with Eastwood High Temp Internal Exhaust Coating help prevent further rusting? It also seems it will help the engine run a bit cooler.

Use the exhaust coating where it's designed to be used. Temperatures inside the combustion chamber is higher than in the exhaust. Any coating on the cylinder will wear away quickly. Coating that flakes off or burns away could create debris that gets caught between the valve and seat causing the valve or seat to burn thru. The best way to keep rust out of an engine is frequent use. If the engine is going to be stored for a long time seal it up. The biggest problem with storing a gas engine is the fuel going bad and forming a solid coating on fuel system parts. Use a fuel stabilizer or remove all fuel before storing.

I agree on old gas being the biggest problem storing engines which is why I use only non-ethanol in all engines except daily driver cars. sorry, I was not exactly clear. I was not considering using it on in the combustion chamber itself but the manifold which is, kinda sorta, like a exhaust header. I would expect the temp in a Mercruiser manifold to be quite a bit lees than of a actual exhaust header that this stuff was designed for as the manifold is water cooled. A lot of my rust was probably due to mice nesting in the manifold, chewed thru exhaust flap.
Right now, I probably need to "side tracked" and focus on getting this boat put back together and in the water. The coating did look pretty cool though.

I don't think it will 'improve' anything...like Lepke stated, the best way to minimize any rust formation is to use the engine frequently...

I'm certain it has some ceramic base so it will have insulating properties...so the engine may run a bit colder than it was designed for...and may take longer to warm up...

The rust formed by not being used, not by using it

Evapo-Rust, great stuff...