mine is a similar combo and i run 3924 autolites.
I agree have had the best luck with NGK's will never go back to anything else in my cars or planes.... And will stay as far away as possiable from champions (junk out the box)Nothing but NGK's
They work pretty good in my lawnmowerI wouldn't call Champions "JUNK", they work great in a "SLO-PAR"!
X2, I've had bad luck with the Champs also.I agree have had the best luck with NGK's will never go back to anything else in my cars or planes.... And will stay as far away as possiable from champions (junk out the box)