Chevy Fanatic

I am looking for plug recommendations for the mods I have done to my engine listed in my signature. I am making approx. 9 lbs boost. Would the NGK TR7IX be my best option?

BullF-16

BR7EFS is what i was running and was highly recommended by my tuner PatG.

Iam Broke

You don't want an extended tip under boost so I'm with Bull. BR7EFS in mine also.

PIDBLSED

Same in mine which were recommended by Frost.

BullF-16

I believe the projected tips are ok for boost just not nitrous friendly. Not 100% sure. Just go BR7EFs

Detoxx03

iTrader: (14)

Non-projected tip like a br7ef. The IX's are good also but leave the TR's and ZR1's alone.

SICK WS 6

iTrader: (7)

So do I read that as meaning TR7ix's are good at 625rw and 13psi?

Chevy Fanatic

Thanks all for the feedback. Can you please help me understand why the plugs GM uses in the ZR1/ZL1 are not the best choice? Is it because of the additional HP I am making? Is the BR7EF a little colder than the ZR1/ZL1 plug? I understand a projected tip plug is a no-no on nitrous assisted cars but what is the issue with the GM plug on a blown car?

BullF-16

IN a nutshell....detonation. The hotter plug under boost... the fuel goes boom before you want it to.....then boom goes your cylinder. Run a colder plug in conjunction with octane in your tank or pull timing as appropriate.

Pick a great tuner and he will take care of you. All tuners have their favorite plugs

Bo White

iTrader: (59)

they ZR1 engine has 9.1:1 compression and the LS3 engine has 10.7:1 so the plug won't be the same with the same amount of boost. I admit I have the ZR1 plugs in my SS and it runs fine but I'm not running the amount of timing a lot of other boosted LS3s run.

Iam Broke

Better to err on the cold side. Less chance of detonation.