ok ive read in a bunch of different places where a 160 thermostat is the best for a dohc engine. and other places say 180. but every parts store ive been to has sold me a 195. now i live in a place where its not even summer yet and the temp is 95. so do i even need a thermostat? jw

 

Yes you need a thermostat , or washer to limit flow because if it flows to fast it will over heat ..

 

Wouldn't the engine overheat if the coolant flow was restricted? At least that's what I thought.. If the coolant is flowing through the radiator when the engine is cold, then the engine will take a really long time to warm up. If it's cold outside, it may never warm up to proper temps. Also, check with the manual. I believe there's a section in owner's manuals for t-stat replacement. If not, I would go by what the dealer says. They have the specs. for your car, and can tell you exactly what degree thermostat you need. You don't have to buy it there, but you should be able to get a GM or ACDelco part no. out of them. Once you have that, then you should be able to get its equivalent from an auto parts store.

 

Thermostats are mainly there to prevent block cracking from my understanding. If water is too cool and is introduced to a hot engine then it will shock the block and make it weak. But on the flip side I think if the coolant was free circulating then the cooling effect wouldn't be as great since it would travel through the radiator faster thus not receiving the cooling effect as much.

Oh and I'd go with a 180* unless you have a ton of mods. With that being said if you see any temps below 25* I'd suggest a 180* also. It has a tendency to not heat up enough in those conditions and will throw codes.

 

i just have an intake and custom exhaust. and i dont have a manual for my car. the first owner neglected to include it when he sold it to my grandmother.

 

and it isnt gonna get below 75 where i live for a long time. the highs are usually in the high 90's. its a grat time to have black leather seats and no ac huh? lol