[Daniel_1stEditionF90]

Trying to get feedback from anyone is using a racing thermostat for the F90 was told by Troy and George that its helping our cars stay alot cooler any feedback would be great.

[BMWDriverX]

Damn haven't touched a thermostat since my Camaro/Mustang days, I wonder where the thermostat even is on the F90

[Daniel_1stEditionF90]

lmao I said the same but from what i'm hearing it REALLY helps due to the heat these F90's put out even with me running Meth.

[cailas]

I saw somethere that it's not "sport" thermostat, it's thermostat from m550xi

[gtenedio]

has this been answered? curious in which thermostat to improve cooling

[FloridaM5]

Originally Posted by gtenedio

has this been answered? curious in which thermostat to improve cooling

This is the one recommended via a gentleman on instagram. I bought it, but have yet to have it installed.
https://www.ecstuning.com/b-hamburg-...37586885-90c~/

[marcvtec]

SO it opens earlier, nice. - when your engine is hot what does it do exactly ?
Seems like not much.

[BMWDriverX]

Originally Posted by FloridaM5

This is the one recommended via a gentleman on instagram. I bought it, but have yet to have it installed.
https://www.ecstuning.com/b-hamburg-...37586885-90c~/

Seen this?

You guys are aware that the car has an electronic thermostat as well as an electronic water pump flow controller.

What i'm trying to say is that this "thermostat" snake oil some people sell is pointless.

https://f90.bimmerpost.com/forums/sh...45&postcount=7

[FloridaM5]

Originally Posted by BMWDriverX

Seen this?

You guys are aware that the car has an electronic thermostat as well as an electronic water pump flow controller.

What i'm trying to say is that this "thermostat" snake oil some people sell is pointless.

https://f90.bimmerpost.com/forums/sh...38;postcount=7

Sure did. I'm not expecting huge changes with this, but coupled with the wmi, water wetter, etc, the sum of the pieces should help out. It's a 100 bucks. Worth a shot.

May just install the wmi system and see how that does with different nozzle sizes and meth mixtures before therm install.

[BMWDriverX]

Originally Posted by FloridaM5

Sure did. I'm not expecting huge changes with this, but coupled with the wmi, water wetter, etc, the sum of the pieces should help out. It's a 100 bucks. Worth a shot.

May just install the wmi system and see how that does with different nozzle sizes and meth mixtures before therm install.

Just wanted to make sure you saw it before you opened up the thermostat housing. From what i gather he is saying that the thermostat is electronically controlled so it wont open no matter what temp thermostat it is as the DME tells the thermostat when to open based on coolant temps.

[FloridaM5]

Originally Posted by BMWDriverX

Just wanted to make sure you saw it before you opened up the thermostat housing. From what i gather he is saying that the thermostat is electronically controlled so it wont open no matter what temp thermostat it is as the DME tells the thermostat when to open based on coolant temps.

Thank you for that; appreciate it. Some conflicting points of view and/or assumptions being made. Not atypical.

[BMWDriverX]

Originally Posted by FloridaM5

Thank you for that; appreciate it. Some conflicting points of view and/or assumptions being made. Not atypical.

Well holy shit! I'm gonna go check my coolant level right now and I'll be ordering that thermostat if it works out for you

[BMWDriverX]

Yeah it seems that BMW probably tops off the coolant every oil change to hide that the car is boiling the coolant off, I was under the min line by a good 6-8oz. My engine has been off for 4 hours and was still pretty hot but not boiling, when i opened the cap some steam coolant still came out. You don't pay attention to something like this and a few hard pulls and bye bye motor.

[Used2be]

Originally Posted by BMWDriverX

Well holy shit! I'm gonna go check my coolant level right now and I'll be ordering that thermostat if it works out for you

I was very surprised when I just checked the coolant level to find it below the minimum mark. Added about 12 oz to bring it up to maximum. I owned an F10 M5 for six years and never added coolant to the engine side of the system. BMW seems to have cured the oil usage problem from the F10, but perhaps we now have some sort of coolant usage to keep an eye on.

It's hard to believe a car as technically advanced as the M5 has no driver warning when the engine coolant level drops below the minimum level. We have an oil temp gauge, but only, I assume, a warning light when the engine coolant becomes too hot? Is there a warning light for engine water temp?

[Daniel_1stEditionF90]

Mo from DME spoke to George and told us to insatll the 90C because it is helping keep these cars 15C cooler so I will be installing mine today will let you guys know how its goes.

[gtenedio]

what does install look like?

i assume this is a clean 6-7 hours to get to and install

[BMWDriverX]

Originally Posted by gtenedio

what does install look like?

i assume this is a clean 6-7 hours to get to and install

Just depends where the thermostat housing is, could be 45 mins if it's two bolts and in an accessible location

[Used2be]

Originally Posted by BMWDriverX

Just depends where the thermostat housing is, could be 45 mins if it's two bolts and in an accessible location

Looks to be a pain in the butt to replace the thermostat. Check out the instructions for hose replacement at www.newtis.info for the F90M5, 17 12 623 Coolant hose for coolant radiator thermostat. BMW loves to vent their systems also, more of a headache.

[Sophisticated Redneck]

Originally Posted by FloridaM5

This is the one recommended via a gentleman on instagram. I bought it, but have yet to have it installed.
https://www.ecstuning.com/b-hamburg-...37586885-90c~/

Originally Posted by FloridaM5

This is the one recommended via a gentleman on instagram. I bought it, but have yet to have it installed.
https://www.ecstuning.com/b-hamburg-...37586885-90c~/

Interesting how this same thermostat works on the F90. I have this on my N63 powered E70, here is what I noticed:

Normal operating temps with stock thermostat were 221-225F, hitting peaks of 230ish in stop and go traffic in AZ summer when 116+ out. I use the torque pro app and have dedicated Android phone mounted just monitoring coolant temps, I still have PTSD from when I was a kid and trying to keep my E21 from overheating in AZ summers.

Switched out to the 90c thermostat, temps immediately dropped to constant 208-210, in sport mode and when a certain throttle threshold is met, the computer takes over drops temps to constant 195-199F. Doesn't matter if it is 70 or 110F out.

So changing the thermostat will drop the temps but not to claimed 90c unless the computer has activated the heating element in the thermostat and this is only done when certain criteria is met. Would be interesting if this is something tuners can tweak in the DME.

Even in F90, the computer does not have complete control over thermostat, only partial control as it is still based off a wax motor. The electrical connection to it is for the heating element, when the computer wants it can activate this heating element to open it thermostat more during period of higher throttle/rpm/boost or sport/M modes.

I did notice a slight performance difference with the thermostat, I would think this would be even more pronounced on the much higher output of the S63TU3 and add extra protection again pre-detention at the higher boost pressures.

I checked out the newtis on this for the F90, looks to be easier to do then on E70 thanks to different water pump design making it much easier to access thermostat bolts, guessing around 6 to 8 hours for average DIY'er taking their time, I would not rush anything on a 120k+ ride.

Filling procedure is the same as it was for the E70, you HAVE to have the vacuum filling unit and must activate the vent procedure after or looking at a sweet 30-50K repair bill for new engine. I used FCPeuros vacuum kit, worked excellent and was amazed how easy it was, pulled in exactly the amount of coolant needed and after vent procedure only had to add less then a 1/4 cup of coolant. Vent procedure can take 15-20min, you have to have low beams and hazards on during, have a proper 15+ amp charger hooked up during procedure.

[gtenedio]

Originally Posted by BMWDriverX

Just depends where the thermostat housing is, could be 45 mins if it's two bolts and in an accessible location

as mentioned, this is a 6-7 hr job

[BMWDriverX]

Originally Posted by Sophisticated Redneck

Interesting how this same thermostat works on the F90. I have this on my N63 powered E70, here is what I noticed:

Normal operating temps with stock thermostat were 221-225F, hitting peaks of 230ish in stop and go traffic in AZ summer when 116+ out. I use the torque pro app and have dedicated Android phone mounted just monitoring coolant temps, I still have PTSD from when I was a kid and trying to keep my E21 from overheating in AZ summers.

Switched out to the 90c thermostat, temps immediately dropped to constant 208-210, in sport mode and when a certain throttle threshold is met, the computer takes over drops temps to constant 195-199F. Doesn't matter if it is 70 or 110F out.

So changing the thermostat will drop the temps but not to claimed 90c unless the computer has activated the heating element in the thermostat and this is only done when certain criteria is met. Would be interesting if this is something tuners can tweak in the DME.

Even in F90, the computer does not have complete control over thermostat, only partial control as it is still based off a wax motor. The electrical connection to it is for the heating element, when the computer wants it can activate this heating element to open it thermostat more during period of higher throttle/rpm/boost or sport/M modes.

I did notice a slight performance difference with the thermostat, I would think this would be even more pronounced on the much higher output of the S63TU3 and add extra protection again pre-detention at the higher boost pressures.

I checked out the newtis on this for the F90, looks to be easier to do then on E70 thanks to different water pump design making it much easier to access thermostat bolts, guessing around 6 to 8 hours for average DIY'er taking their time, I would not rush anything on a 120k+ ride.

Filling procedure is the same as it was for the E70, you HAVE to have the vacuum filling unit and must activate the vent procedure after or looking at a sweet 30-50K repair bill for new engine. I used FCPeuros vacuum kit, worked excellent and was amazed how easy it was, pulled in exactly the amount of coolant needed and after vent procedure only had to add less then a 1/4 cup of coolant. Vent procedure can take 15-20min, you have to have low beams and hazards on during, have a proper 15+ amp charger hooked up during procedure.

What about when you open the reservoir cap to add coolant, i heard gas/steam coming out but filled it to the max line and everything seems to be fine and did not need to be vacuumed. I'm assuming you need to vacuum the system only when you disconnect the thermostat or hoses?

[Sophisticated Redneck]

Originally Posted by BMWDriverX

What about when you open the reservoir cap to add coolant, i heard gas/steam coming out but filled it to the max line and everything seems to be fine and did not need to be vacuumed. I'm assuming you need to vacuum the system only when you disconnect the thermostat or hoses?

Correct, only have to use it when you do something major like thermostat, water pump, or radiator, etc. Or if you had a hose failure that lost alot of coolant, basically anything that dropped the water level low enough that air could get trapped in all the twists and turns in the endless coolant hoses these engines have.

A good indicator of air trapped in the system on the original S63 & N63 was the horrible racket the turbo coolant pump would make. The S63TU3 has an updated pump design so it may not do this anymore but something to be on the lookout for of just in case you ever hear strange screeching/rattling noises after turning off the engine as the pump runs for quite awhile when the engine is off.