Conflicting T-Stat Info
 

It won't hurt anything. It may help you a bit since L36s are pretty knock-prone stock, and N/A engines are alot less likely to detonate when they're running cooler.

You won't run richer or damage your O2 sensor. Your PCM will command the same AFR at 180* that it will at 200*.

Go for it- you probably won't notice huge gains but it may help a bit and certainly won't hurt anything.

thanks a lot for th advice!! and just sayn, ive got the same front liscence plate bowtie on my monte :D

I have a 180 Drilled t stat and I love it! Runs about 10 degrees cooler and takes a lot longer to heat up which is nice, but not in the winter! lol

prolly gonna be the best $17 ill ever spend. haha ill just have to bring some hand warmers for the winter then. :D lol

My 180 tstat hasn't ever been bad in the winter. Now a 160...

I run a drilled 160 now in mine. It's really not bad at all. I programmed my fans to accomodate the 160 and it really helps with heat soak in the summer. I also think it prolongs transmission life, as my trans fluid stays about 20* cooler too.

I definitely felt the difference with my 180 in the winter. Was it enough to care? No.

The only thing that is going to suck about the 180 without a tune, is that your fans won't come on earlier, so in city driving / traffic and such, your car still won't be running much cooler.

Could the fans be controlled sooner by the switch setup that zzp makes?

Yes, but that would become a pain in the butt quickly. You're better just having someone change the fan settings with a tuner.