allena

Hi

I have a 75 corvette with auto, air, stock engine.

I am putting in a Dewitts radiator in it.

What's the best antifreeze to use in it?

Thanx

A

Roughrider

Any good ethylene glycol coolant in a 50-50 mix with water is fine. Brand name, private label...they're made by the same few manufacturers. You can also buy coolant already mixed 50-50 with water.

I would avoid Dex-Cool unless you completely flush the entire system of glycol based coolants and replace every hose. Dex-Cool and ethylene glycol don't mix and will create clogs in the system.

4SPDL81

Check the anti freeze charts...I think a 70/30 mix gives the lowest freezing/highest boiling point protection...you might also want to use distilled water instead of tap water...Good Luck!

Easy Mike

Ask DeWitt's if they have a preference for their radiators.

Street Rat

That is correct they do.

I got a recommendation sheet with my DeWitt's radiator detailing the suggested brands.

rcread

Dewitts recommend Xerex G-05, Peak and Prestone Extended Life. The Peak and Prestone have warnings about mixing with other types of antifreeze.

DUB

For what it is worth:

Regardless of the manufacturer of antifreeze a person chooses....the two main things that should be considered are...

1.) Remove the block drains (one on each side) and completely flush and clean out the coolant system BEFORE the new radiator is installed.......and blowing out the heater core. Do this until the water that comes out of the block is CLEAN.

2.) Using distilled water is a must if you are of the mind set that water is needed in the coolant system...especially if dissimilar metals are involved....meaning...if you have a cast iron block and heads...use distilled water....because you are installing an aluminum radiator.

DUB

mortgageguy

It's not just about the radiator. It's the water pump, the block, and heater core. I converted all my cars to the Preston all makes all models many years ago. Lost two water pumps and a heater core in no time. May be coincidence, but I got away from the all in one antifreeze. I went back to the old green stuff in my vette. All has been well after six or seven years since.

rcread

Are there people of the mindset that water isn't needed in the system? Unless you are buying pre-mixed, it is needed.

DUB

I beg to differ with you....and there are some who have their own views on it also.....as previously commented on in this post.

https://www.corvetteforum.com/forums...-opinions.html

DUB

1974CorvetteJimCr

Not only am I of the mindset that water is not needed, I am using a 100% Waterless Coolant. It is a lifetime product and once installed properly it never has to be changed.

Benefits Over Water-Based Coolants

Eliminates Overheating
Evans Waterless Coolants have a boiling point above 375°F and will not vaporize, thus eliminating overheating, boil-over and after-boil.

Reduces Pressure
Evans Waterless Coolants generate very low vapor pressures reducing stress on engine cooling system components.

Prevents Corrosion
Evans Waterless Coolants contain no water effectively eliminating corrosion and pump cavitation.

Freeze Protection
Evans Waterless Coolants protects below -40ºF

The13Bats

Nice advert...

I looked into this when we talked about it in the last radiator thread,
With the prep involved and the extra costs I can do the same thing with my mix of distilled water anti freeze and no rosion.
http://www.no-rosion.com/norosioncoolant.htm
My main thing against Evans is to only do they not say it will run cooler they admit your engine might run a little hotter, that I don't want and I don't want to pay more to get/risk that.
No coolant can promise no leaks ever.
But just like with the way I do it in my cars and you use evans we each use what works for us and in most cases a nice mix of distilled and green will work just fine so the "best" antifreeze will vary....

1974CorvetteJimCr

rcread

I didn't know that was a thing. I've always mixed mine 50/50 with distilled water.

1974CorvetteJimCr

Conventional ethylene glycol needs to be mixed 50/50. The Evans Waterless Coolant is a mix of ethylene and propylene glycol and can not have no more than 3% of a remnant of water in the cooling system.

C3_ERROR

Not only that it's reusable. So if you every change your motor you can drain the fluid and put it back into the new motor. Amazing stuff.

LeMans Pete

More antifreeze means less efficiency in cooling. I would recommend a 50/50 mixture and based on your locale, more towards 70/30 if freezing point depression is really a concern for you.

Likewise for Evans, you'll see that they state the system runs warmer. Why? Because you have removed water, which has a much larger heat capacity than ethylene glycol.

The13Bats

IS Evans coolant ethylene glycol?
I believe from rooting around it is Propylene Glycol.

Their ( Evans ) website is almost like a covered wagon medicine show with the smell of snake oil in the air.

For example,
That told us a lot "7 herbs and spices"

What you said is right on that Evans runs hotter because water still is best at heat transfer...

Evans with some fun wording wants to convince me that even though my temp gauge is higher my engine is actually running cooler,
I can't help but see images of some spin doc mountebank in a pinch-back suit.

what I would come closer to believing is because their product doesn't boil it allows my engine to run hotter without boil over.
But wait, the right mix of distilled water and antifreeze will raise the boiling point and the engine will be cooler than with Evans.

Don't get me wrong this was like the Qjet carb or nitrogen in tires to me I wanted it to be my magic answer for lower temps not that my Dewitts will give me cooling issues.

I know for some Evans is what they desire but the costs and hassles teamed with possible higher temps will keep me from being an Evans user ( unless the Evans rep reads this and wants to sponser my car with free product heck I will even run a big old Evens decal on my fender )

I would believe that people who do use it love it because in most all cases those people have top end cooling systems anyway....they will not have cooling issues ( or shouldn't ) no matter what coolant they used.

LeMans Pete

I do believe Evans is propylene glycol, which is hardly any better than ethylene glycol. Both have nearly half the heat capacity of water.

If your system is operating properly, boil over shouldn't be a concern. If it isn't, I wouldn't use Evans as a fix because you still have a cooling problem - solve the cooling issue, don't band-aid it with a different type of coolant.

lurch59

Let's talk about what Evans will, and will not do. Radiators that have a large temperature difference between the ambient air and the radiator will be more efficient at shedding heat. So, what is the ideal operating temp of a gasoline engine? Evans claim to fame is eliminating hot spots in the cylinder head because it doesn't boil. As has been stated, a mix of standard antifreeze and water transfers heat more readily than pure propylene glycol: however, we are talking apples and oranges because you must factor in steam, which is likely present around the exhaust seats, and propylene glycol is far more efficient at transferring heat than steam.

Come on everybody, when was the last time you checked your radiator cap to see if it holds proper pressure? Even if it is holding pressure, some steam forms hence the anti foams in antifreeze.

Your radiator has to be appropriately sized, Evans will not overcome that. But, it's nice not to have to rely on pressure to prevent boiling.

Waterless coolant stops corrosion, eliminates electrolysis, and prevents cavitation. It's not snake oil, it's physics. I run Evans in everything I own, but I keep my stuff for a long time and I tired of flushes and radiator maintenance, and replacing heater cores. The anti corrosion additives are a poor compromise at best, due to the water in the system.