Pedro Valdez wrote:
> I spotted a listing on eBay what claimed: Available for all new style
> LS series engine that have a separate thermostat and water neck.
> These thermostats are available in 160, 180 and 195°F temperatures to
> suit any application. Mr. Gasket's 2005 Pontiac GTO test car gained 5
> hp with the 180° unit.
>
> Surely if you were testing maximum power on a dyno, the engine would
> warm up beyond the standard 195 degrees. How can it make a
> difference? More likely the extra HP came from somebody turning off
> the aircon.

The LS factory thermostat is 186 degrees, plus unlike other engines it
is in the return side of the system not the water outlet. Normally the
LS runs right around 190-195 with the stock thermostat.
I know of a few folks who have pulled the thermostat just to see what
the thermal ability of the system is and on a 75-80 degree day the
coolant temps ran in the 170s at speed with 50/50 dexcool.

With some programming and the right tweaks I could see a gain with the
180 as that would put the coolant around the 185 degree range. I doubt
it would be 5hp but ? Would likely get more of a gain if you were to
reroute the air intake out where they were in high pressure areas and
insulate them from the underhood temps.

--
Steve W.