MHP

MHP is now offering modified stock/MB (180F open temperature) Thermostats.

The primary benefits of a lower open temperature thermostat are the consistant performance and increased engine engine life. The relatively high open temp stock thermostat assures reduced emissions and therefore isn't optimal for performance applications as the ECU pulls timing when seeing higher ECTs (Engine Coolant Temps).

Lower coolant temps equate to increased engine longevity/durability and allow us to use more aggressive timing tables when custom ECU or ECU/TCU tuning, though even when stock the OEM ECU calibration won't have to pull as much (if any) timing due to heat soak--equating to more consistant performance. Next to detonation/preignition and excessive rpm, heat is the next largest killer of engines.

Real world testing with our own C63 has shown significant reductions in ECTs, 15-25F less depending on application, environment, and driving situation. With the OEM/stock Thermostat we averaged 194-204F ECTs while cruising at 75-80mph. Post MHP T-stat install, we see a consistant 174-180F at the same speed. We also have not witnessed the coolant temp rise above 194F, even after hard WOT beatings, and in stop and go traffic.

When paired with our ECU or ECU/TCU tuning, which turns the cooling fans on earlier, the heatsoak issue with 63s is completely resolved.

Price is $279.99 shipped in the Continental U.S. via UPS/FedEx Ground.

Glock Guru

Good job. BTW, I know it not really the same thing , but did you see a lower oil temp from the lower water temp?

MHP

Troy,
Coolant temp only. It was 65-70F here for the past 2 days and cruising at 80-90 I stayed below 180F coolant temp. You can tell the motor definitely likes the lack of heat.
We also manipulate on/off temps for the fans so between the two (T-stat,Tuning) we should have the heatsoak issue covered even in stop and go traffic in the middle of summer.

Glock Guru

Great news.

gsrjc

Is this beneficial even if I don't plan to upgrade anything on the car? Also, how difficult is it to install?

MHP

Yes, it will benefit even a stock car. The OEM ECU cal pulls timing when ECU temps rise to help prevent detonation. Allowing the motor to run cooler keeps ECT temps down and timing in the tune.
Install is kind of a PITA. ~2hrs on a C63. Even a dealer won't be able to tell the difference between it and a stock T-stat (since it's an internally modified stock T-stat) so you could have them do it NP.

Thanks

gsrjc

Thanks for the quick response. Wow, 2 hours just to install that must be a PITA.

MHP

NP. Definitely not like on a domestic application. It's not hard, just tedious.


Thanks

wan888

Can you please advice where to order this part?

thx

MHP

PM otw.

Thanks
Andy

Stangar

I don't want to get into trouble regarding this issue, and I applaud your efforts to keep the car cool, but I find it amazing that a T-stat would cost $280.00. What would the stock one cost? I'm beginning to think I wouldn't be able to afford this car.

MHP

A new 63 T-stat from MB is ~$180 then factor in $10-13 for insured priority shipping with delivery confirmation via USPS.

bluert

IMHO, to take full advantage of a cooler/lower temp. thermostat, you need to recalibrate your fans to turn on sooner at a lower temperature. It is fine when your car is in motion but once it sits idling/in traffic for any length of time, your temp will still rises until when the fans comes on.

MHP

Glock Guru

So you can change the fan turn on temp with your ECM mods?


-Troy

MHP

Yes.

bluert

IMO, everyone should do both at the same time. There's no point of just getting only the thermostat without the ecu/tcu tuning.

MHP

We agree.

You will see benefits of just our T-stat on the highway or while at constant speed cruising, just not in stop and go traffic.

hcy

any pictures

MHP

They look 100% identical to a stock 63 Thermostat.

qship5

Andy,

Other than being a time consuming install, is this a DIY for those of us that have done a reasonable amount of work on cars? Does it require any specialized tools?

Thanks,

Mike

MHP

Mike,
Nothing special at all, just a bit cumbersome due to the location. Any seasoned wrench turner can put it in.

Thanks
Andy

c32used

mthis

andy works great. i got it installed 2 weeks ago i think and its great the cooling temp dont pass 200 yet. i been tring to pass 200 but cant doit (maybe to cold out)

BerBer63

My coolant temp has never gone over 199 in aggressive or traffic driving, even with my oil at its max temp that I've seen around 233-234F.