Hey guys just getting some parts rounded up for my new engine. I was wondering what spark plugs I should run. Here is what I have.
515cid
9.3to1 comp
dart pro 1 (310cc) heads
hyd roller camshaft
dart intake
900cfm AED carb
Going to the dyno next wed I hope, but would like to get an idea of where to start with plugs. Old comb made 616hp 645tq with a 509, iron 320cc merlin heads,same hyd roller cam, same intake and a BG 850 carb.
Anyway Dart recommends a autolite # 3933 Std tip, race
or a autolite # 3911 projected tip

Thanks for the help.
Erik

The Autolite racing AR3933 would be my first choice.

NGK racing R5671A-7
Eddie

Eddie, any interference with the stereo when running a non-resistor plug?

Not at all. Those are the only plugs I have ever run and I've yet to have any interference with any electronics. I guess most are far enough away to not affect it, since most of the head units are all the way in the cabin.
Eddie

Thanks for the reply. I'll take a look at them NGK's
Erik