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Ok so I've had my beast for about 4 months now(bought back at the end of jan) and I've gotten ALOT of great info from these forums so I figured I'd contribute. I came across the "0 pressure" coolant in another forum and thought about the high pressures my 540 ran. Thought it would be great upgrade to the cooling system. Again did more research, found out it was waterless coolant yada yada. Anyway there was a lot of negative feedback but it was all from people that had never even tried it. Backyard engineers making there own assumptions. I did see that a lot of supercharged/turbocharged engines benefited from it. So I weighed out the pros and cons and being the stubborn person I am bought it and are now posting my results. Figured if it went bad the worst I was out of was the cost of the coolant. Now I don't have a decent start point seeing as how it was the middle of winter, temps were stuck at about 174 (bad t-stat I guess), and a worn clutch fan. But here are the new figures after a month. Using a snap-on solus ultra, a 80c stant t-stat, outside temp was 90f, ac on max, in direct sunlight, I had a max coolant temp of 208f, oil temp of 212f, and intake temp (which is prob inaccurate anyway) of 150f. 65 Highway speed in 6th with ac those numbers were 195 coolant, 200 oil, and about 123-127 intake. Those same conditions with the ac off resulted in 184-5 coolant, 189-90 oil, and no real change in intake air. In colder climates like 75f at night those temps are pretty consistent. About a degree less and intake dropped to about 113. I even tried with ac on the highway in 5th and still the same 195 coolant and 200 oil. I've so far had no leaks, overheating issues, or modifications other than the thermostat and new clutch. I will post new mpg figures when possible. The old figures in the winter as it started warming up I was able to get about 290 miles to a tank average. Cracked 300 like twice lol. Anywho that was with a bad t-stat but now I'm using ac so my new numbers won't be accurate untill we get a nice 70 degree week. Well there it is in a very large nutshell. Also these were all using 93 octane gas and 15w50 Mobil one oil. Tire pressures at 32/35 front/rear. Hope this helps anybody with questions regarding the evans coolant
 

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Interesting to read this as I'm mighty close to using Evans when I replace my valley pan gasket at the weekend.

I know mine's an M62 but it's regular temp is 109 degrees and very keen to try and do what I can to make the cooling system as maintenance free as possible. I've replaced most of the major components and thinking with the reduced pressure this should make things run nicely.

My only concern is that Evans seems to make an engine run slightly hotter and as the M62 seems to run at quite a high temp already I don't really want it running any hotter. I know that a hotter engine can run a bit more efficiently but looking at your temps the S62 seems to run cooler which is a good thing in my book.

I'm posting as I think it's useful to discuss the Evans coolant's pros & cons so hopefully I'm not causing any problem by talking about an M62 in the M5 forum.
 

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Discussion Starter #3
I wish I had numbers before hand but I had too many components not working properly and it was winter. But givin that without the ac my temps were only about 10 degrees warmer than the t-stat regulating temp. And I believe with thermostats there is a margin of error. A lot of members also state how they're t stats drop a couple of degrees over the course of a couple months. One reason why I went with the 80c instead of the 79c (I think that's stock). The other is I kinda wanted a warmer engine for things like the cats and secondary air issue. The fact that at it's max it was only 208 is pretty good with me. And if the temps ARE slightly higher than one would like or what's factory, just drop a lower rated t stat in. I believe that excessive pressure and corrosion are more of a concern especially when there is no way to modify those like you can temps. I plan to take it to a few track sessions this season and will comment on those temps as well. I'd like to see how evans works on a system that doesn't already have both a high flow pump and t stat. And again I have no issues at all with leaking
 

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As a side note on Evans, I used it on my road race motorcycle for years, a Ducati 998 with the fan removed. We werent allowed to run regular radiator coolant on the track.

I never had a single leak or issue, even on the hottest days. The only thing I did was drained the Evans in winter time because it was in an unheated garage and the Evans for motorcycles was susceptible to freezing.

Im not sure if that helps anyone but thought I would mention my experiences with it.

Rick
 

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As a side note on Evans, I used it on my road race motorcycle for years, a Ducati 998 with the fan removed. We werent allowed to run regular radiator coolant on the track.

I never had a single leak or issue, even on the hottest days. The only thing I did was drained the Evans in winter time because it was in an unheated garage and the Evans for motorcycles was susceptible to freezing.

Im not sure if that helps anyone but thought I would mention my experiences with it.

Rick
A decent amount of water would have to be in it then otherwise it shouldn't freeze. Even a 50/50 mix of BMW coolant won't freeze in -40. Water is also more effective at removing heat so it likely has more water than coolant.

OP, thanks for the info and your Stant T-Stat is likely 82C/180F.
 

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I don't want to be a skeptic here (waterless coolants are quite cool :) ), but I don't think we'd see much benefit in the M5 since the setpoint temperature is unusually low, as is the radiator pressure.

I've seen the needle in the red (around 115 deg C, stuck thermostat) and don't recall having significant coolant boil off.

It may work for other cars, but for the M5 I think money's better spent elsewhere.
 

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Discussion Starter #9
Ok with that being said I went and measured pressure as well. Using my snap on pressure tester @ 195f I got 7lbs of pressure. I'd be interested now to see what the pressure would be using 50/50


Sent from AutoGuide.com Free App
 

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A decent amount of water would have to be in it then otherwise it shouldn't freeze. Even a 50/50 mix of BMW coolant won't freeze in -40. Water is also more effective at removing heat so it likely has more water than coolant.
You are correct, but since the Evans motorcycle mixture was made to cool, not to keep from freezing that is why I removed it during the winter.

I didnt worry about freezing tempatures during the race season.
 
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