Hi guys, just picked up a 99 Z that's pretty much a stocker, and I'm still learning the LS1 world. Did a search but couldn't find anything concrete for my year, is the stock thermostat for a 99 a 195 or 180? Does it have the temp stamped into it like other tstats?

Just trying to see what I have and not duplicate any work that's already been done to it. (for example the lid's been gutted already)

thanks guys,
tim

 

All ls1's came with a 195 temp thermostat. I can't tell you if it is stamped on. If you put a cooler thermostat on you will have to reprogram your computer to deal with it.

 

ok thanks.

 

Look in the owners manual, mine says 180 stock. You could also pull it and look inside - if I remember correctly it was stamped 86*C on the copper part.

 

holding my stock one in my hand, curious where its stamped?

its gm part 12558852.

I searched and found the new part that superceed's that ... is 12567563

which people claim is a 180.

I see, its stamped in the end of the copper part. 86 *c = 186.8 *f. pretty much Right in the middle of 180 and 195. lol.

so who knows.