I'm toying with the idea of getting an aftermarket thermostat. Based on opinion the stock radiator has significant thermal capacity left to sink more heat, but most don't advocate changing the thermostat given reliability concerns. However all things considered, I wanted to address two particular potential benefits with the lower coolant temp on my setup:
1. Oil cooling. I'm on the Forester water to oil exchanger and having a larger coolant to oil temperature delta will further reduce oil temperatures.
2. Knock resistance - lower coolant and oil temps would influence cylinder head and bore temps, reducing the tendency to knock. This opens up further tuning potential.
There's several choices of thermostats available for our cars:
1. SARD 68C/82C
2. Mishimoto 76C
3. Billion 65C/72C/82C
4. NTCL 82C
Common sense will tell that the 82C and 76C ones are who want a drop in... it is very unlikely the stock radiator has enough cooling capacity for the 65C/68C, so those can be easily singled out. From owners' feedback in Minkara in regards to the SARD 82C thermostat the coolant typically settles around 84-86C, and as reference mine on OEM goes about 89-90C on a normal day and 92C on track, this is at night though.
The car is stock NA and I'm aware of the potential pitfalls - I'm familiar enough to address tuning related issues, but I wanted to find out from others' experience if it has opened further headway for more spark advance and knock relief. @
tomm.brz @
steve99 you are my usual go to guys... any thoughts on this? Based on the stock tune (A01G), having a thermostat with an idle warmed up coolant temp at 81C is enough to clear any warmup corrections/compensations, apart from the radiator fan temps. Based on this the Mishimoto seems to hit the spot; I'm aware of the quality issues though.
@
JIM THEO seen in a previous post that you have the SARD thermostat installed - any feedback is appreciated.
For reference the stock thermostat opens at 88C and is fully open at 95C.