I am struggling to find a suitable non-resistor spark plug to suit iron heads (14mm x 1.25mm, 13/16" hex, 3/8" reach) that has a cold heat range.

I would love an NGK BP9S but they don't appear to make them.

Application is blown olds 455 drinking E85 with ICE 10amp ignition (hence non-resistor plugs required). Strictly a drag/bracket race car.

Does anyone have any recommendations? Advice from engine builders (consulted several) is that a NGK heat range 9 is a good starting point.

Thanks,

Dan

 

Maybe talk to Brisk?
https://briskusa.com/

I run NGK 8Rs in my 12.5:1 468

 

Is this too cold ?
https://www.ngk.com/ngk-96461-b-6l-b...g-blister-pack

 

Been thru that looking for plugs for perf flatheads i build. Champion and ngk have discontinued most if not all of the non resistor automotive plugs
they apparently can have the top unscrewed and resistor removed

 

not cold enough lol

 

curious. Didnt really want to muck with the internals.

Have a lot of 30 new B9S coming that I found online, but they wont last forever.