http://www.summitracing.com/parts/NGK-5632/

BCPR6E-11

I currently run these in my mostly street driven 10.75:1 comp Stealth headed 446. It has 20 initial and 36 total and does not ping with 93 octane. The motor has a quench style dome piston and I can run a projected tip plug.

I am planning on racing it in a couple of weeks and am concerned I may not have the the correct plug in it for that. This NGKR5671A-7 non-projected tip seems to be the suggested plug. Am I leaving something on the table with the hotter plugs?

Anyone else have a similar combo that they street/strip?

I like and use the projected tip spark plugs in everythnig I own, as long as they fit The number 6 NGK heat range is probally marginal for your combination, I woudl use the # 7 projected tip NGK or a Champion RC9YC

I`m at 12.11 comp and have street driven and raced w/the NGK 7` and 8`s and they were about the same et wise but the 7`s live longer ESPECIALLY on the street.