RADEoN

iTrader: (12)

I built a 408 to replace my spun rod bearing LS6, and my tuner made me take my ngk tr55ix plugs out and put tr6 copper plugs in. The car has audible knocking at high rpm with until they pull some timing, then it goes away.

Would the wrong plugs cause this?

Bowtie70SS

iTrader: (10)

The wrong plugs can cause preignition and detonation. As NGK plugs go 2 is the hottest and 10 is the coldest. Backwards of normal thinking. A combination of aggressive timing and the wrong plugs can/will cause this issue as would a lean condition.

Bowtie70SS

iTrader: (10)

http://www.kaila.net/tl125/tl125ngkcode.html

soundengineer

iTrader: (16)

depends on compression...
same as stock compression 10:1 ish, then use an NGK tr55
if you are 11:1 ish, use an NGK TR6
if you are 12:1, use an NGK TR7

soundengineer

iTrader: (16)

that is not backwards of normal thinking... plugs have always been Higher number heat range is a Colder plug...

opposite of Rating how hot a girl is....
but its correct if you are rating how cool the Fonze is...

Sales3@Texas-Speed

iTrader: (2)

Thats is exactly what I was going to recommend.

1nasty86

iTrader: (63)

11.3 compression and I'm using a tr6.... no issues so far..

MillsMotorvation

Hate to break in but im runnig a boosted 5.3, boost at 14/15psi. Wanting to order NGKs from Summit, but what exactly is the part number for the TR6. I just dont want to get the wrong kind, or wrong thread design, or what ever. What do I need to get? Will the tip be projected?

Jontall

TR6 NGK Part # 4177 and Rockauto has the best prices.

ScottyBG

@ MillsMotorvation - Advance usually stocks them, if you don't want to wait to mail order them. For some reason Autozone and O'Reiley don't?, At least my local ones didn't. When you go into an autoparts store today, they can't seem to find it unless you can tell them what car it is for. If they look up anything with an LS7, like a 2009 Z06 vette, the TR6 is the stock plug for an LS7, and they will be able to set you on it. Jontall is correct on the NGK number 4177.

soundengineer

iTrader: (16)

on 15 psi.. you probably want to be on a #8 plug and a .025 gap

RezinTexas

Would the TR6IX iridium plugs be the same heat range as the TR6? Is the only difference longevity compared to the TR6 copper plugs?