Gents,

I need new plugs. I've run NGK Iridiums on my track car for years. I've used the 6-11 and 7-11 since going FI. I've got a Rotrex equipped NB1 putting out about 225 rwhp with ~10psi boost. What's the current thinking on heat range and gap?

Thanks,

 

BKR7EIX, .032” gap. At 10psi, if you have a strong ignition I would try the -11 with the .043” (1.1mm) gap. If your not doing extended high speed driving, the 6 heat range would be fine.