I just put in a 180 tstat, without replacing the gasket. I dont think its leaking though(yet) . But its still running at about 200 degrees, maybe 197. why? does the thing have to be turned a certain way in the tstat housing?

Was the old paper gasket in one piece when you took it apart? That'* amazing. Mine was stuck on and I had to scrape it off.

But it'* normal for it to still get up to 200. It will happen if you're in the city, stopping at red lights, etc. You have to be driving pretty constantly so air will be rushing in the radiator, and then you will run cooler.

I'm sure someone else can explain more in detail on when the stat opens, etc...

Just by chance, what brand of stat did you purchase?

Stant

I had the same question. Check out this thread...

http://www.bonnevilleclub.com/forum/...pic.php?t=6588

According to Shawn (dbtk2) the temp guage on the 2K+ cars pretty much always read around 200. I havent tested this yet with the autotap to see what the actual coolant temp is but I'm guessing GM didnt want ppl freaking out when the temp went above 215 and the fans kicked in to cool it back down to 200. Something about a jumping guage I guess...