I second all that ragragtimetime said - the hotter thermostat makes these run better and not too hot - the earlier trucks used to have 180 degree stats for us and 195 for canada - I swapped Geronimo's stat for a 195 and never had a problem with him running. I also run an equivalent platinum version of the NGK and a MSD blaster coil and Nology wires, with the timing at 10 btdc