Aftermarket thermostats

[tomm.brz]

Originally Posted by JIM THEO

I do have the fans adjusted to lower temps but this just gives an extra margin before temp rises, how your fans cool the engine while thermostat is closed?

An example: https://datazap.me/u/jim-theo/log-16...=0-29-30-31-45

you don't have them set properly and they don't start then, to reach 95 at idle (i was expecting a log of the 102C while stationary??)

my fans start @ 89C and at that temperature the thermostat is already a bit opened and coolant flows and actually it will cool itself to 87C (temp of actual start of opening of OEM thermostat) and then fan stops and start creeping again to 89-90 and start the loop again
there is NO WAY to reach over 100 while stationary if you use the fans earlier

[Compelica]

Originally Posted by nikitopo

I have a Cosworth thermostat 76C (not the one from Mishimoto). The coolant temperature sits at around 80C-82C depending how hard I drive. Oil temperature is also a few degrees lower even without an oil cooler. These are non-idle temperatures where the heat exchanger can work.

Nice, stock radiator as well?

[JIM THEO]

Originally Posted by tomm.brz

you don't have them set properly and they don't start then, to reach 95 at idle (i was expecting a log of the 102C while stationary??)

my fans start @ 89C and at that temperature the thermostat is already a bit opened and coolant flows and actually it will cool itself to 87C (temp of actual start of opening of OEM thermostat) and then fan stops and start creeping again to 89-90 and start the loop again
there is NO WAY to reach over 100 while stationary if you use the fans earlier

When I reached the 102C it was stock radiator w/ ft86club fan maps that work fine with the NTCL 82C thermostat.
If I remember right, I have only a Techstream video recorded with my mobile phone not uploaded datazap logs.
Now I have CSG maps with adjusted earlier the fan maps and works as in the log you see.

By the way the same period Steve99 logged his car for me and this is what he answered:

"I tested my car again today when temps 35C on way home

While driving coolant max 93

when i stopped and reved car while stationary got to 100 max then fans cut in and back to 97 max within 30 seconds"

[tomm.brz]

Temps while driving depends also on the load, it's normal and ok to reach 93C, and anyway fans are off while driving

again i just think your tune, and steve's tune, have higher kick-in temp than me... from the log i would say your fans kick in around 95C, steve's around 100

Can't really prove it for you as it s too cold now but in my 4 years of constantly retuning my car and flashing it over 810 times, I tested also this
and coolant will flow to the radiator starting from 87-88C and if you start the fans (even just one of them actually) at 88 or 89C, your coolant temp at idle even in the summer won't pass 90C

And will keep lower temp also if you rev while stationary, you won't even reach 95C while revving if the fans are moving
You could always ask the tuner what temp he set

That to say: if you changed thermostat just to adress that particular behaviour, the fans starting earlier would just "fix" it

[nikitopo]

Originally Posted by Compelica

Nice, stock radiator as well?

Yes. Stock radiator.

[Compelica]

@JIM THEO do you know at which temperature the SARD 82C is fully open?

[JIM THEO]

Originally Posted by Compelica

@JIM THEO do you know at which temperature the SARD 82C is fully open?

It is the exact same technology thermostat with the factory one, it starts to open at 82C degrees and 6-7C degrees higher it is fully open.

NTCL 82C vs SARD 82C

https://shopee.com.my/82%C2%B0C-NTCL...50.12416930827
https://www.nengun.com/sard/cooling-thermostat

[Compelica]

Originally Posted by JIM THEO

It is the exact same technology thermostat with the factory one, it starts to open at 82C degrees and 6-7C degrees higher it is fully open.

NTCL 82C vs SARD 82C

https://shopee.com.my/82%C2%B0C-NTCL...50.12416930827
https://www.nengun.com/sard/cooling-thermostat

Thanks. Didn't see it officially mentioned in stores or on the website itself so was wondering if that detail was on the product manual

[Compelica]

Anyone looking to explore this option summarizes the gains and drawbacks here in this post.

https://www.ericthecarguy.com/forums...p-thermostats/

[nikitopo]

Yes it is true. The low temp thermostat will lower engine temps so it buys you head room in hot climates, it does not increase the cooling capacity but will buy you time. Personally, I removed the A/C radiator which sits in front of the cooling radiator. So, the cooling capacity is also better. If you don't upgrade somehow your radiator, then an aftermarket thermostat might not worth it as much.

[NoHaveMSG]

Originally Posted by nikitopo

Yes it is true. The low temp thermostat will lower engine temps so it buys you head room in hot climates, it does not increase the cooling capacity but will buy you time. Personally, I removed the A/C radiator which sits in front of the cooling radiator. So, the cooling capacity is also better. If you don't upgrade somehow your radiator, then an aftermarket thermostat might not worth it as much.

I have done the same and it is little to no improvement. You are not really moving any more air since there is no where for it to go. Getting air out via hood ducting helps quite a bit though I understand that is not practical for a street car.

My car is running no AC condenser, Koyo radiator, stock thermostat and a hood duct. Car also has a splitter on the front.

My water temps stabilize at average 197f(92.8C) during trackdays under 90f(32C) ambient over the course of a 20-30 minute session. Peaks are about 199f. Stock radiator is really not much worse as far as peak temps, just takes less time to get there.

Pic of typical session. This was around 85f ambient I think. I don't remember exactly.

[nikitopo]

Originally Posted by NoHaveMSG

My car is running no AC condenser, Koyo radiator, stock thermostat and a hood duct. Car also has a splitter on the front.

It makes sense if you are using a stock thermostat. You need to use an aftermarket thermostat and adjust also the ECU to start the fans in a lower temperature.

[NoHaveMSG]

Originally Posted by nikitopo

It makes sense if you are using a stock thermostat. You need to use an aftermarket thermostat and adjust also the ECU to start the fans in a lower temperature.

I run mine on a manual switch to full on. The fans don’t really do much once the car is up to cruising speeds on the road or above. I just run them on pit out or if the car is idling when at temp.

[Compelica]

I have my preliminary results of the 82C thermostat I had recently fitted. I had the coolant swapped from a 60/40 to a 70/30 water to coolant ratio as well in the process. To give an idea - freeze temperatures now have changed from -35C to -15C.

With ambient temperatures at 36C and cruising at 100kmh in 6th, coolant was at 86-88C (previously 89-90C) and oil temperatures at 91C (previously 93C). On idle, coolant stays at 88C though I should be able to run it slightly cooler by changing the fan trigger points.

Will run another test at night, where ambient typically falls to 26C.