Also the cooler thermostat will not allow the water vapor in your oil to
evaporate, and this will promote sludge and acid formation. The main
advantage to the 160º thermostats that I have seen, is that they have a
larger diameter water passage and therefore, I suppose, allow higher flow
for rock crawling with a big engine, which you do not have.

Knock and ping can be due to too low octane fuel, or the timing mark on your
harmonic balancer having slipped. Putting in a cooler thermostat isn't
going to fix that. Check TDC with a dial gauge or something before being so
sure that your timing is "dead on".

Earle

"Mike Romain" > wrote in message
...
> It needs to warm up above 190 to be sure the inaccurate sensors actually
> turn on and switch the computer into 'warmed up' mode. Otherwise the
> computer stays in basic 'cold' mode and you burn a lot of gas.
>
> You also will lose internal heat with a cold t-stat in the winter.
>
> Even with no computer still working in my 86 258, I get better mileage
> with a hot engine.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's
> Canadian Off Road Trips Photos: Non members can still view!
> Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> (More Off Road album links at bottom of the view page)
>
> Kevin wrote:
> >
> > Are there any advantages/disadvantages to using a 160 deg. thermostat
> > versus a 195 deg. thermostat? I have a lot of knock and ping that I
> > suspect is due to excessive temps in the combustion chamber since my
> > timing seems dead on. The temp gauge fluctuates between 190 and 210
> > deg. depending on how fast I'm traveling. Also the clerk said the smog
> > police would fail me if they saw I was running a cooler thermostat. Do
> > they care what temp my car runs at? If it matters I have a 1987
> > Wrangler YJ 258 ci Carter BBD, 5 speed manual. Any input is
> > appreciated.
> > Thanks,
> > Kevin