Lawnboy

iTrader: (54)

NGK Iridium IX Spark Plugs
i was thinking on a set of TR6-IX or TR7-IX Iridium plugs,

will be making 15 PSI on a forged 347 with a D1-sc, hopping for 700 RWHP.

why me

i thought Iridium was bad?

ls 2 goat

I'm running the TR7-IX but will be going with the denso's when I throw the F1 on here.

Firebirdfan

As did I. Don't you want to run copper plugs with boosted cars? Copper readily absorbs and disappates heat whereas iridium absorbs it and holds it. The hotter the plug, the more likely detonation is to occur. So I've always known that running a copper plug that gets hot during combustion, then cools relatively quickly is better than an iridium plug that gets hot, and stays hot through all cycles of the motor.

MY99TAWS6

iTrader: (3)

You are talking platinum plugs are bad for nitrous and boosted applications. Iridium is fine and is used in many many boosted cars. Copper plugs are annoying requiring frequent changing. And every time you change plugs especially in aluminum heads you risk damage to the heads.Antisieze of course is a good idea on plugs that go into aluminum heads.

So rest easy you can run iridium. What heat range will depend but would think at lower levels like say 8psi the 6ix would be fine. At higher say past 8 to 15 likey 7 ix would be fine and maybe past 15 8ix. Guess person will have to monitor things and check plugs to see how they are doing. I am running 6 ix currently and so far keeping boost around the 8psi range.

MY99TAWS6

iTrader: (3)

Here is shop running boost and nitrous with iridium plugs..no problems.

"Our shop truck routinely sees 15lbs of boost and two stages of nitrous. The plugs that reside in this motor are Denso Iridiums (which happen to have the finest thickness electrode of the bunch) and cylinder temperatures become outrageously high very quickly with the complex nature and behavior of forced induction and nitrous. The addition of this plug allowed me to run a larger gap without blow out, have a great idle quality and while our plug changes are just as frequent as copper, the plugs appear to be in better fashion. So just to initiate some friendly conversation I ask prove to me why Iridium is a poor choice in a nitrous application?

On a side note, I would not consider longevity to be the best quality of Iridium…I would have to say the improved spark control and energy consumption are the two leading benefits."

MY99TAWS6

iTrader: (3)

In my aps instructions it gives tr55 for boost below 8psi ambient temps below 60f stock exhaust
it shows tr6 general street with cat back exhaust boost 8 to 9 ambient temp 60 to 100f
it then shows two iridiums tr7ix drag racing 60 to 100f and tr8ix road racing over 100ft
So they obviously feel iridium is fine for boost. No boost levels mentioned in the last two recommendations but would assume since racing it would be 8 to 20.

why me

what about those pulse star things? any good word on them?

Lawnboy

iTrader: (54)

the word on them is $25 each!

HUNTER02SS

iTrader: (24)

When you change the plugs as often as you would a copper core plug, then it becomes a pricing issue. I run AR3934 in my motor. Good enough for nascar, good enough for me!

Shawn @ VA Speed

iTrader: (3)

i run plain old autolite copper in all of our boosted stuff,ar 103 for std ls stuff

98Camarod

iTrader: (43)

Thats a 6, whats the 7 and 8 equivalent do you know?

mondi2002

iTrader: (11)

I have been running BKR7EIX-11 (6988) Plug for over a year. (Same as TR7-IX but gasketed, because I have Dart heads) They have been working great and even eliminated a low speed stumble I had. I am running 10-12psi boost w/9.5 CR.
Have never seen any knock with various tunes and temps. No meth either.