180 Thermostat for an 8.1L?

[bcfitzsimons]

Does anyone know where I can buy a 180 degree thermostat for a 2002 8.1L?  I'm in Cleveland, Ohio.  Anywhere online?

 

The reason I need it is my 8.1L pings really badly on regular gas after the dealer uploaded a new computer flash to it.  Running 89 octane takes the ping away completely.  GM service reps and the zone manager have looked at the truck, and kept it for about 4 weeks at the dealership, all to tell me that everything on the truck is working as it should-except for the ping/knock under throttle.  So they offered me a 6 yr, 100000 mile warranty.

 

Anyway, colder copper plugs, plus 89 gas, and the knock is gone.  I'm wondering if a 180 thermostat would help prevent any preignition that I'm NOT hearing.  If it would, should I even try a 160?  Or will this totally screw with the ECM and foul my converter?  Emissions testing isn't a big deal to me because the truck is registered commercial, so it doesn't get emissions-tested-

 

Thanks-Fitz. :thumb: