I'm new to the forums, done lots of searching trying to locate a cooler t-stat for my 2004 E55.

I Pm'd PTE last week but no reply.

Anyone have any suggestions?

-David

If you can find one, let us know how long it takes for your check engine light to come on.

The computer is going to expect to see a certain temperature range, after a couple cycles of irregular or under desired temperature operation, you are going to trigger that CEL. Unless you have STAR with developer mode or know someone who does, I'm not sure you will be able to get around the light.

Also, with split cooling and other upgrades to the cooling system to battle heat soak, is there even a purpose to doing this on modern FI cars?

Not trying to shoot your idea down, I'm just curious.

Ha! just saw this is your first post. Welcome!

Talk to me about that. I read a number of threads and my understanding was that unless you go super cold, CEL issues aren't a problem.

Did I get it wrong?

-David

I see you are in Texas, I am in West Central Florida we probably have some of the same high temp battles.

I'm not looking for a 160F, but frankly, if I could snag a 170-180F it would suit me just fine.

I'm an "old" guy with tons of modding experience both inside and outside of the "euro-zone". I realize it won't do much if anything for IATs but I'm hoping that it will keep things a little more reigned in on seriously hot days.

-David

Where abouts in west central florida? I have family in Citrus county and I'm in that area/tampa bay area often.

I don't know for sure, but i'm sure the stock thermostat is somewhere in the 180 range. The engine software i'm sure is written to work most optimally for performance and emissions wise with the stock thermostat. Weather or not the car makes any changes to the overall performance when it sees an issue with lower than desired coolant temp? I'm not sure. hopefully one of our more seasoned vets can chime in here.

The big battle with our cars is heat soak of the superchargers charge air cooling system. If you read around or do some simple searches, you will find a seemingly infinite amount of good information on how to combat this best.

What do you plan on doing with the car?

Check out this website http://www.modernhorsepower.com

For a track rat, sure.

For a daily driven vehicle, I see no point. Your typical H/E, pump, -10C mod etc. or just the killer chiller setup is more than sufficient.

Also make sure you read about that vendor works ethics, some people are happy, a lot of people are not.

You can use the t stat from the clk 55 which is a 160 but I can't remember the part number

I'm in Sarasota, about 50 miles south of Tampa. Drop me a note when you're headed down next!

The stock t-stat is actually 190F and the car will run right around 200 or so in normal driving. The software is, in fact, designed to run at these temps however, it is quite dynamic in terms of its response to minor adjustments such as I'm pursuing.

I have been lurking for several months and have read extensively on the subject. I am not necessarily trying to combat heat soak or high IATs (though both WILL be impacted by a slightly cooler coolant temp) I am simply trying to bring the cylinder head temps down 20F or so.

I will be pursuing the heat exchanger and I/C pump upgrades to address the charge air temps directly.

-David

Ultimately, I plan on building a fairly mean street car. My last project was a New Generation SAAB turbo convertible that started life making 185HP at the crank and ended up making 342 at the wheels on a stock framed turbo. My build sheet was most unorthodox but the car made 360+ wtq and ran 60-90 in 3rd gear in about 3.5s. Considering the uber-cheapness of the platform and the very limited mods, it was a decent showing.

I must admit, I've been building all types of cars for over 25 years, I'm a former shop owner / technician and I love a good contrarian path.

One thing I LOVE about the AMG forum community is that I have been able to find GREAT information upon which to formulate my build path. You guys have tested just about everything and God love you for it.

-David

Lots of good stuff there. Thanks!

-David

Well, as I mentioned above, it really depends on what you are trying to accomplish. For this particular mod, I want to accomplish a 20F drop in coolant temp which will result in cooler cylinder head temps. For charge air cooling, the H/E, Pump and KC options are all potential pieces of the puzzle.

As a side note, the -10C mod, done on a stock car with a stock t-stat, will simply have the fans working against the t-stat. I currently use the menu to run the fans at a higher speed to maintain temps around 88C or so but if the t-stat were a little cooler, the fan would not need to run at a higher speed like that. Meanwhile, I've actually clocked the car through measured runs and there IS a performance benefit to keeping the coolant temps between 85C and 90C. If left completely unfettered by the fans, the cars will run about 95C.

-David

THANK YOU for mentioning that. A little due diligence is a good thing when it comes to choosing vendors.

-David

Thanks HD. I have followed your car on Dragtimes. You sound like my kind of builder. Nice times, great work.

My understanding is that the t-stat is part of the housing. Is it a big deal to swap them out?

-David

From what I remember on my build the neck of the housing is for the clk55 is shorter so we took the thermostat out of the clk housing and put it inside of my stock housing. It doesn't quite fit as the stock thermostat but it fits in the housing well enough to satisfy my tech. I think I got it from discountparts.com

On drag times I will update with my 10sec runs soon but I'm not sure if I'm done racing the car. I achieved 10's on my fourth run after modding the car then I went out a different day and made only one run and beat my previous time by a tenth & increased my mph in full street trim other than drag radials so I believe that she's got more in her the way she sits now before going to a lighter battery, front runners, seat removal etc.....oh and a lighter driver.