Cooling Ideas

Just be careful which coolant you mix them with. Google "Water Wetter Brown Slime".

 

It seems to me at first that such solutions have only two applications, in situations where hot spots in an engine are a problem (racing) and as patchwork for masking other problems / postponing solutions. The problem is, the cooling system was designed to work with normal coolant. If it doesn't, something is wrong and you're not going to solve it using different coolant. Yes plain water etc can reduce temps and conduct more heat away from the engine - but something is still not right. If a cooling system has become so critical you have to revert to these kind of things, imho you need to solve the problem which is most likely a clogged radiator (in- or externally!), and collapsed steam hoses.

Running plain water with an anti corrosion package for better heat transfer is what this discussion is mostly about. That does seem to have benefits in heat challenged engines - I'd be very wary about anti corrosion properties and freeze risk as drawbacks though.

That said there was someone on this forum who had a piston liner that corroded to the point of being holed(!) due to cavitation, likely because of hotspotting but possibly the use of bad fuel (detonation can cause this too, it is a problem far more commonly seen in diesels). Perhaps it would have been avoided with this. Never say never.

 

I would stay away.

The car needs Glysantin. Harder to come by these days but worth the search.

If this would be me I would start by flushing the system once with plain water. Filling up with 50/50 antifreeze. Keep it in for about 500 km and flush again, then finally fill with Glysantin.

In the end you should have a funky yellow coolant. If it still runs hot, time to get the radiator out.