I know most run water meth.
But for those who run water alone,
What effects will running 20 % denatured alcohol have on combustion?
I plan on running to 20 % alcohol for winter freeze protection.

Are there any benefits running it year round?

I read alcohol has a lower flash point than diesel. But I don't know how it will effect combustion / cylinder pressure / combustion temps.

 

I don't know about running denatured alcohol but if it's similar to methanol it will somewhat advance your timing which increases cylinder pressures. 20% should be safe. Read up some more because I am no expert. Many here would suggest water only. I picked up around 30hp with around 20%windshield washer fluid and 80% water filled in my tank. That probably equated to only 10% or so of alcohol. Hard to tell exactly what gain I had because I was running a slightly different tune from a previous dyno session. Water does keep temps down and that's what I needed it for primarily.