Tuning for Fuel Economy

Do you think the additional 10F would also slightly increase your probabilities of knocking?

Factory is 172F, so it's extra 20F. Probably though especially on hot days, but you can pull timing via ECT correction table. Also any efficiency gains will be negated if you don't adjust the radiator fan tables to be higher (factory fan is on at 203-205F...).

The reason I went with 190F, is because the Ascent uses 190F temp range too, while 2010-12 LGT uses 182F (10F warmer then ours, fitment unknown). Also my NA 2012 Outback uses a 190F stat, that DOES fit, but since it's NA it has less heat to worry about.

Just to confirm what i think you're saying, that the 2010-12 LGT and Ascent thermostats are all a direct replacement from a mechanical size perspective? the difference being the T-stat opening temp. I like the idea of at least moving to a 10-12 LGT T-stat, since i don't track and rarely really boost mine. and moving to 182 or 192 could offset the warmup "issue" that kept me from getting the fancy koyorad, which would also be a great addition to the change. The T-stat would set your lower temp and the much more efficient all Al koyorad would keep you from going much higher.

honestly, you need to set up a paypal or patreon account.

Just to confirm what i think you're saying, that the 2010-12 LGT and Ascent thermostats are all a direct replacement from a mechanical size perspective? the difference being the T-stat opening temp. I like the idea of at least moving to a 10-12 LGT T-stat, since i don't track and rarely really boost mine. and moving to 182 or 192 could offset the warmup "issue" that kept me from getting the fancy koyorad, which would also be a great addition to the change. The T-stat would set your lower temp and the much more efficient all Al koyorad would keep you from going much higher.

 

honestly, you need to set up a paypal or patreon account.

Sorry for the confusion, I meant they use the same temps, that's not to say they will or will not fit.

I installed 21200AA200, which is for EJ253 Legacy and Outbacks and is 88C:

https://parts.subaru.com/p/Subaru__/THERMO-ASSEMBLY/49231072/21200AA200.html

Here's part numbers for the various years:

2005 GT: 78c(172f): 21200AA072 (Stock)

2010-12 GT 84c(183f): 21200AA230 (Should fit because EJ255)

2012 2.5i 88c(190f): 21200AA200 (Confirmed Fits)

2020 Ascent 88c (190F): 21210AA190 (will not fit, but same temp range): https://parts.subaru.com/p/Subaru__/THERMO-AND-GASKET-ASSEMBLY/49231121/21210AA190.html

I do have a Paypal account and will admit my testing has slowed down due to tighter budget, harder to justify almost $20 in gas, just to test a part. If you want to be generous and would like to contribute to the testing gas money fund, send me a PM .