I run AC 41-104 ZR1 plugs at 9 and 12 psi.

 

the correct way to actually do it is put a cold enough plug to burn the cadnium off the strap, too cold and it wont burn off, too hot and it will look ashy, a 7 would take a ls motor to 800rwhp or so on gasoline, ive run tr6 heat range up to 1200-1300 flywheel hp on E85

 

I think at 15 psi, it's time to at least start looking at the 7.

 

i was originally planning on going with the BR7EF's so now i feel better about that, what are most of you gapping them at with your boost levels?

 

run between 10-16# and got them gapped at .028. .026-.030 should be alright.

 

Ive always run Tr-6 @ .035'' Never an issue.

Since its topic would the 7 be a better plug ? For Safety or Performance or both??

 

For you, maybe since you are not running meth. I have a new set of non projected 6's (BR6ef?)that I am going to put in mine once I am back. I would go with a non project tip Tim.

 

Bref7s.... Proven and safer imo

 

How about the 8's?

 

I had 9's in mine at 23 psi, I think 8's would have been better as the coating was still on the ground strap at 20* of timing.

My fuel was apparently off pretty bad too, so who knows.

I don't think 8's would become necessary till 20+psi