A good question by Greg, and some good dialogue on pros/cons - and civil too; much different than what I'd expect to evolve to on the C8 forum due to a somewhat different skew of personality types there. It's great to have and share opinions, but some there provide some pretty childish entertainment.

Greg, never used Evans but I've been tempted a few times. For me, I spent the $ on upgrading the stock cooling system on our L71 - all refurbed stock parts with the exception of a direct fit Dewitt's radiator and a 180 degree thermostat (and I know some on this forum would say I wasted $ on the Dewitt's - that they're too expensive, etc., and that's okay. But I only winced once - great fit, extremely well built, and it works as advertised). All I can say about my experience is - wow! 100+ degree days and the thing runs 180 in traffic, on the highway, on canyon roads, etc. I'm not concerned about corrosion - I'll change the 50/50 mix of the good old green stuff periodically and it will likely outlast me.

Best, Paul

 

I agree about the specialized apps.
How much heat ? Enough to boil the coolant.
You would need to know the temp rise of coolant, the flow rate of the coolant and the specific gravity of the coolant. there is a formula (Q=500 X GPM X Temp difference). Q is the heat tranfer in BTU's/hr. There is also a correction factor for the fluid's density.
But, I digress, I like to use water wetter in my cooling systems. It reduces the surface tension of the coolant thereby allowing the bubbles to break free, thereby increasing heat transfer (no bubbles on the water jacker surfaces to impede heat transfer. No need for Evans for my applications.

 

I would think that Evans has this same lower surface tension property and that is one of the benefits. I just do as you do, Dewitt's radiator, 50/50 green stuff, and a bottle of water wetter.

 

yadkin's right, Water has a higher heat capacity. What this means is water can absorb more heat before rising in temperature. Think of flowing coolant as a conveyor belt to remove heat. Because water has more heat capacity, think of it as a wider conveyor belt. For either system, as long as the conveyor belt is running fast enough (water pump turning fast enough), no problem, all the heat can be removed. Sit in traffic sit the engine idling, however, and all of a sudden the narrower slowly moving conveyor belt gets overwhelmed. That's why Evans makes excuses for a higher coolant temp - their coolant can't handle as much heat as water can.

They try to deflect from this by spouting BS about pressure cycles causing fatigue - but last time I checked, OEM cooling systems were designed to be pressurized.

You guys talking about bubbles - I assume you're talking about localized hot spots, since most cooling systems run cooler than the boiling point of water. Those hot spots are still going to be there whether you use water or evans; except the combustion chamber side of those hot spots is going to be hotter using that evans coolant, since the evans coolant runs hotter than water.

I used to be neutral on this subject, until a couple of us in the Impala SS club tried it out. What we found was that the car runs significantly hotter when idling in traffic, like 220-240 even with a 160 deg thermostat, which caused the car's ECM to pull timing. For you carb guys, that means the ECM was trying to reduce the chance of detonation; running hotter means you're that much closer to detonation, especially considering today's crappy gas.

At the drag strip, we found two things.
1) The evans cars tended to run a couple of tenths slower, with a lower mph through the traps, than they had previously under the same weather conditions, again due to the ECM pulling timing as the coolant heated up over the course of the drag run.
2) They evans cars were not as consistent as before. This is important in bracket racing, which is what we were mainly doing. We think this was a combination of the lower heat capacity of the evans causing wider swings in coolant temp as we were lining up at the starting line, and the aforementioned timing issue.

The cars ran faster and more consistently with water. Period. In the end, we considered it lesson learned and went back to straight water (with a corrosion inhibitor) in the summer and 50/50 in the winter.

 

I'm curious, are you able to provide any similar feedback from non-computer controlled cars under the same conditions?
Cheers, Greg

 

Sorry, I don't have any personal experience with non-computer controlled cars. However, I don't see why the coolant temps in traffic would be any different. On the drag racing performance, I know for a fact that hotter air going into the engine produces less power. So just the fact that the intake manifold and heads are going to run hotter with the evans coolant than water, is going to cost you power. How much it actually does, you'd have to experiment to find out.

Evans was originally developed for off-road racing, where radiators can get clogged with mud and dirt. If your cooling system becomes compromised, the evans will sometimes enable you to limp along and make it to the finish line or at least to a pit stop, because of its high boiling point, where water would increase pressure until you blew a coolant hose and went out of the race. But it doesn't make you faster or work better than water for street driving or road racing.

Evans is just trying to find a new market, selling to street vehicles.

 

Thanks for the feedback.
I'm not at the critical edge where every tenth of a second matters for me. I'm just living in a very hot climate looking for every advantage I can find.
I think your info (and the outrageous cost involved) has helped to decide this product probably will not change things in my circumstances.

 

What, you never go mudding in your vette?

 

If it never freezes at your place, the optimum coolant is straight water with a corrosion package poured in, like water wetter, or prestone also makes a bottle of corrosion inhibitor. Something else that works well would be a zinc sacrificial anode, like ships use to keep steel hulls from corroding in salt water. If you can find some Stop Leak that uses zinc powder, that would probably be the best corrosion inhibitor of all. I'm not sure offhand if copper leak stop would work as a corrosion inhibitor, I don't know off the top of my head whether aluminum or copper is higher on the reactivity scale of metals. Assuming you have an aluminum radiator. But the point is, if your cooling system is in good working order, straight water with a corrosion inhibitor is the absolute best option.

Anyway, glad I could help.

 

Check this website out. Particularly, Tech Tip #4. http://www.stewartwaterpumps.com/
These guys make the water pumps used by nearly every NASCAR team.

 

Hmm... I was okay until I came to this:

"Clutch-style fans are inconsistent and we do not recommend their use for any application, if possible."

Not for ANY application? Seriously?

Live well,

SJW

 

Stewart pump tech tips are for racers and not street cars, for the most part. Maybe that wasn't noticed in their tech tips.

 

When are we going to discuss entropy and enthalpy? The laws of thermodynamics? The thermostat doesn't give a *** about, specific density, specific heat, specific brake horse power, specific fuel consumption or anything else specific nor heat transfer rate, density of coolant, type of coolant, etc. But it does respond to temperature and changes in temperature. The wax pellet inside will modulate the varying opening and closing of the valve over a temperature range of up to 35*F through expansion and contraction of the pellet relative to the temperature of the coolant only. The coolant gets hotter under load, the wax expands more exerting force on the spring to open further allowing more cooler coolant to flow into the block thereby displacing or forcing out the hotter coolant in the block which thereby cools the engine and then the wax pellet cools causing it to contract resulting in the valve closing to slow the coolant flow in order to maintain normal engine operating temperature, PERIOD!!! Not rocket science. A simple device in a control system to correct offset.

 

OK, what current applications use a clutch style fan? If there's an application where a clutch style fan works better, then there should be modern vehicles using it.

 

Because its pretty hard to mount a radiator on an inner fender when the engine is installed transversely. Also, auto makers must comply with fuel efficiency legislation. So aluminium rad/electric fan arrangements are more efficient thereby saving on gas. It won't be much but every little bit saved here and there helps out overall for a more fuel efficient car. They don't use this arrangement for performance but do modify the arrangement for more specialty high performance cars like later model vettes. Again, their tech tips are for racers.

 

This. Tough to beat straight water for cooling an engine. I doubt you'll ever need antifreeze in Palm Springs. I used to alternate straight water in the summer and make it 50/50 antifreeze in the winter on my old truck with a flathead here in MN. "Coolant" is just a marketing gimmick by the antifreeze manufacturers to make people think it's necessary for cooling when it actually hinders cooling.

 

How does it hinder cooling?

 

I personally use only the finest (cheapest) plain old green coolant in my Vette

 

Because ethylene glycol has a lower specific heat capacity which means it takes less energy to heat up an antifreeze solution a given number of degrees than than it does water. The only downside to water is a lower boiling point than antifreeze but we can compensate for that with slightly more pressure on the cooling system.

If I lived in a warm climate and had a vehicle with cooling issues the first thing I would do is get rid of the "coolant" and put in straight water. Just add some corrosion inhibitor and you're done. It's almost free and it WILL help.

 

Transverse engine is why they use electric fans? What about rear wheel drive cars?