Waterless coolant

[Diesel_Dave]

It makes sense to me that, according to the report, the coolant itself didn't affect FE at all, whereas increasing the coolant temp did have a 3% improvement. So the coolant enabled a benefit, but didn't give a benefit directly. It would have been interesting to see what would have happened if they had run the conventional coolant at the higher temperature.

[Vekke]

Modified Thermostat for higher MPG's... - TDIClub Forums

There is a long post on TDIclub on the topic. Gains come from no need for fan and frictions are lower with higher engine temperatures etc. You do need to make some modifications to get the gains from that stuff. I might test that evanscooling stuff this summer on my lupo...

[G2TDI]

Originally Posted by Vekke

I might test that evanscooling stuff this summer on my lupo...

Did you?

[Phantom]

I have thought of making my own evans from what I have found it is propalene glycol ~70% with 30% being ethaline glycol. they added the EG to thin it out so it is easier to pump when cold. The only reason that it "out performs water" is because water can boil on hot spots and the boiling prevents the coolant from touching the metal to remove more heat.

[G2TDI]

Originally Posted by Phantom

I have thought of making my own evans from what I have found it is propalene glycol ~70% with 30% being ethaline glycol. they added the EG to thin it out so it is easier to pump when cold. The only reason that it "out performs water" is because water can boil on hot spots and the boiling prevents the coolant from touching the metal to remove more heat.

Yeah I had considered that too to make it myself but didn't want to find out the hard way that I didn't do the appropriate mix

[Big Dave]

It is not easy finding thermostats that will allow exploiting the high boiling point of the glycol mixture.

You'd also have to temper down your heater/defroster temps. I have a 203 degree stat and the heater will burn your fingers and the defroster will crack the wiondshield in extreme conditions.

[G2TDI]

Originally Posted by Big Dave

It is not easy finding thermostats that will allow exploiting the high boiling point of the glycol mixture.

You'd also have to temper down your heater/defroster temps. I have a 203 degree stat and the heater will burn your fingers and the defroster will crack the wiondshield in extreme conditions.

Here's an interesting thread about 205F thermostats

Modified Thermostat for higher MPG's... - TDIClub Forums

As for the heater I just have as manual as it comes so I can adjust it whatever way I want.

[ConnClark]

I thought I would chime in on this. The biggest gain from running a higher temp thermostat is that the combustion gasses loose less energy to the cylinder walls and head, thus providing energy for the piston to extract to make the wheels go around. Having the cooling fan come on less is miniscule by comparison.

[Blue Angel]

Originally Posted by Old Tele man

...the SAE paper projected a 2-4% FE increase with change from 190ºF to 215ºF thermostat, but didn't get it:

http://www.evanscooling.com/assets/p...vans-final.pdf

Actually, they got a nice 3% gain when raising the coolant temperature. Adding the coolant alone did nothing to improve economy, but when taking advantage of the coolant's higher boiling point and raising the operating temp to 215 the predicted efficiency gain was realized.

Also note that the cooling fans were locked "on" full time in both trucks to eliminate them as a variable. This probably had minimal effect on the outcome while traveling at high speeds/airflows, but in a city environment at lower speeds with stop and go thrown in, the potential for reduced fan on time could offer another advantage in efficiency.

Most people I see arguing against the Evans product hang their hat on the cooling capacity of pure water being much higher, but in reality most people run a 50/50 mix which has a much lower heat capacity than straight water, though still higher than Evans.

I'm very interested in this coolant. The only two things that hold me back from trying it are questions relating to performance with thermosyphoning tank style block heaters, and heater core performance in extreme cold. There's just not much information out there.

[Cobb]

Good question, depends on where the mpg improvements comes from. Is it less effort for the water pump, power not needed for the electric or mechanical fan, is it allowing more aero mods or is a poorly cooled engine able to maintain and run advance vs retarded timing?

I use water wetter in my insight and I think it helps to run the grill block I do and maintain. For the hell of it I ran with a full block last summer and I got better mpg having the cooling fan run vs having enough air flow for it to maintain on its own.