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Quote:

Originally Posted by DaleClark (Post 12512819)

Evans is a great product but it's not for me. If I'm in the back woods of North Carolina and have a coolant hose fail, I can simply repair it and fill the coolant with regular Prestone and I'm back on the road. Not so with using an exotic coolant.

I only recommend Evans in specific use cases. For the majority of people, Prestone and distilled water is all you need. It's cheap, it's easily available, and with doing a drain and fill every year or two you will have a spotless cooling system. I've gone through engines with a LOT of miles (like 150-160,000) and were treated with Prestone as stated, they had spotless bright clean cooling passages.

IMHO there's no good reason to try something else. This car is exotic enough as it is.

Dale

I've been doing an annual "drain the radiator only" procedure (drains ~1/2 of the coolant) and refill with 50/50 NAPA green/distilled water for ~25 years now. Very easy and quick to do. That keeps the anti-corrosion chemicals replenished. Drained coolant always looks good, and no issues so far.

So I decided to just go with the "classic" Prestone - although I did go with the pre-mix version. Saves a step as I'm just going to mix it to 50/50 anyway.

Reviewing the Product Safety Data Sheet for each of the varieties (Classic and Asian (Green)) the only difference I could see was in the reported pH.

Classic pH: 8.4 - 9.0
Asian pH: 8.0 - 8.6

No idea what that indicates about their respective formulations, but it was the only thing I could see. As I mentioned above - I've just gone with the Classic.

FYI,
Original Evans NPG is about 99% undiluted Propylene Glycol with their proprietary protection package.

Evans NPG+ is undiluted 70% Ethylene Glycol and 30% PG. You can request Evans for their SDS.

It's not much different that running high quality straight undiluted EG or PG coolant which I decided to do in all cars in my house that I maintain.
Not a single overheating issue even with the FD on track days or back roads / mountain driving with AC on and 95F ambient temp.
All running low or zero pressure by removing the bottom seal at the cap and never worrying about boiling or rust as happens with water.