In the March Eurotuner magazine they said their MCS suffered a significant power loss as it got hot - as much as 22hp at the wheels. They said they installed a 180 degree thermostat and the power remained consistent, even after repeated dyno runs. They feel it's the most important upgrade Cooper S owners can make.

What do you guys think? It's on page 70 of the magazine.

A 180 degree thermostat, what is the temp of the stock thermostat? 180 is pretty normal.

Steve

They didn't say? I have no idea what the stock is either......

Brad

We used to take a thermostat and put it in a pot of water on the stove with a kitchen thermometer, turn the heat up and wait for it to open while watching the thermometer.


Does that still work?

email the guys at m7 tuning...they sell a 180 thermostat and would be able to tell you what the stock one is :smile:

Believe stock stat is 225F

Even though there is a power loss from the heat, and better emissions, there is another reason for this temp. It is effective for boiling out any moisture in the oil system.

2001?

http://www.eurotuner.com/toc/

225F (approx, IIRC it is slightly below that) is the temp that the radiator fan kicks in. The thermostat operates around 195F, at least in my car. Data is from using a CarChip.

Scott
90SM

Another CarChip here... I too can confirm 195. While doing some spirited driving, captured at 5 second intervals:

94
194
194
192.2
192.2
192.2
194
194
194
194
194
195.8
195.8
195.8
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
194
195.8
194
194
194
194
194
194
194
194
194
194
194
195.8
195.8
197.6
195.8
195.8
194
194

If you live in "cold" area though, M7 might advise you not to get his 180 tstat...

Interesting first-hand data...thanks for sharing

Out of interest, would you consider the rainy, sodden climate of the UK as a 'cold' area??

Cheers,

Henry

Hi there Henry. That is why I put the word "cold" in quotes as I'm not totally certain... I did hear that if the lowest temps one would see are in the low 30's F (0 C), then this mod shouldn't pose any issues...

While I live in sunny CA, I reside in a canyon that often sees the 20's in the Winter, and an occasional high teen. Peter of M7 advised that I might not want to order this from him...

Thanks Tony for your insightful reply.:smile:
I have a thermostat, as well as a technology pulley on the way from M7 as soon as the pulley is made available. I just wanted to be sure that the thermostat would be ok for the UK's regional climate. From the sounds of things, it should be fine since Peter has sold me that the thermostat without question, plus we don't see such harsh temps over here...only rain, lol
Cheers,

Henry

You are quite welcome! Yeah, he just got his pulley done yesterday, and I think today it goes-in for the special coating. Take care.

05 DS/W MCS "Simon"
I've been running OBD Gauge http://qcontinuum.org/obdgauge/index.htm
for the last couple of weeks. The water temp has been indicating between 189 - 191. This is with OAT between 41 - 73 F. I'm guessing it's has a 191 F. setting.

Well, here's more confirmation that there is variation in all manufacturing (not that I needed to learn that lesson again).


I got a new OEM MINI thermostat, and the coolant temp is now regulating around 189F and is steadier than the previous thermostat that cycled around 195F. I was getting the occasional fault code with the original t-stat. It was replaced (by Miniguru of Way Moterworks) at about 61,000 miles.

As any fyi, I've seen the official tolerances for some other thermostats so I know that they are not all exactly the same. The example I'm giving is a nominal 180F t-stat, but they meet print as long as all examples are fully closed by 175F and fully open by 203F.

Scott
90SM

Glad I wasn't the only one that caught that one:smile:

It was Turner Motor Sports that recommended the 180 thermostat. I have a new MCS with JCW kit. I e-mailed the chief engineer at JCW and he said you should not have any problems with 180 degree thermostat and it should not throw any fault codes. I bought one from Turner ($45) and installed it. No problems. I live in sunny Southern California and the car works great. Even in Palm Springs (112 degress) it ran cool (water - 190 degress max).

Why would a lower thermostat setting not be suitable to colder climates?

MCS came out in 2002. And classics weren't made in 01.

didnt the new mini come out in 01 in europe?

yeah, it did, but not in S form.

Ahhh oky doky sounds god to me.

While high heat is bad, cold is as well. The oil cooler on the MCS is cooled by the coolant. Oil needs to be close to 212 degrees F to burn off the water that condenses in it. When the outside temp is very cold, the coolant will be flowing by the oil at temps much colder. This will keep the oil too cold and not allow it to burn off the contaminants in it. On hot days, the water is going to be in the upper 100's so it's fine.