Best coolant is water!
Originally posted by Drop Top
Anti-freeze is not just for freezing weather. It also helps cool the motor along with the lubrcating ability for your water pump. ALWAYS run the corect amout of anti-freeze year around. Its also a good idea to change and flush the radiator it once a year. This helps to keep the electolisous (spelling) down witch is what eats away at the aluminum. .............
Sorry to be so blunt, but this is NOT the best way to protect or provide max cooling for our engines/trans or most others. Having done this in the desert for over 30 years, I can assure you this is one area of expertise I have LOTS of experience and done LOTS of research.
First, water transfers heat from a metal surface much better than antifreeze. So this takes more heat from the engine and disipates it better in the radiator.
Strikeeagle is correct in using RMI and water in the summer for the best protection and to run cooler in the summer. Since we do not have freezing weather here in the winter, we can do without antifreeze ever.
If you are in an area that has winter freeze, add the RMI to it as well. Most a/f has a minimum additive package and it is quickly used up. The white junk you see around the tubes inside the radiator is silicate drop-out from the antifreeze. The RMI will prevent this.
When a cooling system is properly maintained, serviced and uses the proper products, reliability and performance is GREATLY enhanced. A simple flush twice a year will give long life to any cooling system.
As far a recommending RMI-25 as THE radiator additive, this is also as result of many years of experience. This product has been used extensively in the commercial and industrial fields for 30 years. It is the only product I have found that cleans, lubricates, inhibits and conditions the cooling sytem. This is why companies like Cummings, Cat and others use, and recommend it.
Unlike WaterWetter, it will not go corrosive/acidic and prevents electrolysis. For those with aluminum heads, this is the best protection you can give them. As the only additive than cleans while being used, it provides better heat transfer that way, as well as the surficant for breaking down surface tension.
Final note, especially for a race car, do NOT use any antifreeze unless the car is just being stored. It takes only a small amount to contaminate the oil if a head gasket blows. This small amount is enough to ruin bearings. Cars with RMI that were contaminated with a blown head gasket had the oiling system completely flushed are still running good.
For late model vehicles that MUST use "coolant" for warranty reasons,we find the periodic addition of RMI lowers operating temps and keeps the system clean. Antifreeze, which is ethlene-glycol, does not wear out. It does become contaminated and/or the additives go away.