How'* your gauge read after the 180 Tstat install?
I put the 180 Tstat in Saturday, and it runs cooler, but I can sure tell when it opens, because the gauge drops down to the hash mark for 150 degrees, then slowly goes back up to about where 180 would be, then down again. Ambient temp has been 30-40 degrees, and it'* been in-town driving. I'm pretty sure I bleed all the air out.
I was thinking it would hold a little more steady at the 180 mark. Maybe it will in hotter weather.
Do Tstats open fully all the way as soon as the coolant hits the rated temp or do they gradually open as it gets hotter until they are fully open? I always thought they kind of gradually opened at the rated temp, and kept gradually opening as the coolant exceeded the rated Tstat temp, but I don't know where I got that from.
1996 Olds LS, 198,900 miles: RIP...