[GDRAFT]

New 289, a little more than stock, 30 over pistons, which thermostat do i get.....160, 180, 190 etc? THX

[butchd88]

i have a 66 289 with same pistons,i like the 160 because with the cyl. walls being a little thinner it might run a little hotter,especially at idle.i am in fl.and you in ca.and the weather tends to get a little warm,i like to keep the mustang cool.
hope this helps,butch

[Print Dad]

Hello,
For sure 160 is my opinion.

butchd88 summed it up nicely. Print Dad

[Jonk67]

I would go 180 at least, at 160* your engine never fully warms up, 185*-195* is operating temp., engine gets near or above this and the Tstat opens to circulate cooler fluid to level the engine temp out. Running a 160* IMO is too low and your Tstat will be opening too often not giving the fluid in the rad. time to cool and most threads I've read report that they overheat sooner with a 160* because the hot water just keeps circulating much like not having a Tstat at all.
Engines wear more at lower constant temps., according to the last paragraph on this site (which is inline with others I have read) your engine wears 2X as fast at 160 as it does at 185 Cobra Valley's Balanced Thermostats

I'm sure this'll be a thought provoking subject which is good.
Jon

[jcp123]

Originally Posted by Jonk67

I would go 180 at least, at 160* your engine never fully warms up, 185*-195* is operating temp., engine gets near or above this and the Tstat opens to circulate cooler fluid to level the engine temp out. Running a 160* IMO is too low and your Tstat will be opening too often not giving the fluid in the rad. time to cool and most threads I've read report that they overheat sooner with a 160* because the hot water just keeps circulating much like not having a Tstat at all.
Engines wear more at lower constant temps., according to the last paragraph on this site (which is inline with others I have read) your engine wears 2X as fast at 160 as it does at 185 Cobra Valley's Balanced Thermostats

I'm sure this'll be a thought provoking subject which is good.
Jon

This is more or less what I was going to say. I put a 180* in place of my 160* a few months ago and have never looked back.

A 160* thermostat won't really let it get warm enough when it's cool out, yet when it's warm enough for the engine to run, say, 200* on its own, well, it won't matter whether you have a 160* or 180*, because it's warm enough for the tstat be open anyway. It won't lower your peak temps. Might as well get the tstat the motor calls for.