I just put in a 160 stat...however stock gauge still shows just under 210 when the car is hot like the stock one did. Is this because I had the car tunned before I installed it? I cant see why a new stat would be bad. Any ideas...did this happen to any one else that put these in?

 

Thermostat only has authority over the -minimum- coolant
temp. Maximum is set by coolant flow, fans (electric), air
flow to the radiator and engine waste heat output all
together (hopefully, cooling flows and radiator effectiveness,
exceed waste heat output and then the thermostat ends up
in charge). But LS1 F-bodies have dinky radiators, fans that
are set not to run intil stupid high temps (factory) and temp
gauges (except for '98) that are just a hoax, to make the
buyer think they were getting a real one.

If the tune didn't set your fans to be on low by 175F and
high by 180F you won't see anything worthwhile from a lower
temp 'stat. Leaving aside the question of whether lower temp
is actually worthwhile on a low-mods aluminum head motor.

 

I have an 11 sec car that has been tunned and running ls6 ported heads....So are you saying I need my fans tunned to get any effect from the 160?

 

Another thing to consider is that the tstat temp is where it just starts to open, it isn't fully open until maybe 15 deg. higher. (I verified this once for my stock 180 stat.) So even without changing fan settings you'll see a lower average temp with the 160 because the radiator cooling alone can take it below 190 depending on outside temp. I think ideal would be a 170 tstat (but haven't seen one) along with bigger radiator and lower fan settings. Too low is bad also.

 

another thing to consider is the 99+ has a dummy gauge & pretty much anything in the 170+ range will sit at the 210 marker. Not to say that it isn't running at 210 because that would depending on the driving condition( ie steady cruise you might get down to 165-170 with that thermo but if your sitting idle & the fans arent turning on you'll see the ect temp go up dramatically) and fan settings themselves.

 

I wondered about this! My '99 Z28 seems to always point just below 210 when its warmed up even when I see variations of coolant temp.

 

the needle/gauge on the car is OFF....u won't notice a difference. mine is a 160therm and i didn't notice a change in the gauge in the car when i swapped from stock to 160...

i mean wait...yes you all are seeing things mine works fine