What Plugs for T-1

[LtMash1A]

What spark plugs are you T-1 guys using?
Thanks/David

[Cobra4B]

I know NKG TR-55's are good for lsx motors, but I don't know what T-1 guys run.

[DJWorm]

I like the Beru Silverstones from Nology and I run Magnecor KV85 race Wires.

I initially considered the Nology Hot Wires but did not opt for them as at the time I could not see any advantage. However Nology has produced some dyno results that may change my mind.

[Subdriver]

I use plain old ACDelco Professional Platinum plugs, 8#41-974.
GM part number 12563707.
I buy mine straight from gmpartsdirect.com.
I do change them more often than the typical daily driver.
I honestly don't know what the rule is on spark plugs for SCCA T1. I just got my new 2004 GCRs tonight. I'll have to read through it and see if there are any specific rules regarding spark plugs.

[David Pintaric]

I don't think the GCR addresses it. So you can go two ways with this:

The conservative way is to take the stance that if the GCR does not specifically say you can change something: you cannot. In this case you must you stock plugs.

The "aggressive" approach is to put whatever you want in, and I doubt anyone would protest (even if they knew about the change), nor do I think you would be bounced from tech if it was questioned.

I personally don't think the switch will make much of a difference.

[DJWorm]

17.1.8 Touring category
D. Modifications
1. Engine
g. Ignition/Starter/Electrical System
1. Spark Plugs may be substituted
2. The use of resistor or non-resistor-type plugs
are permitted

This is from my old GCR not a current '04 ones.

[Subdriver]

From the 2004 GCR:
17.1.8.D.1.g.1: Spark plugs may be substituted.

I have several boxes of the stock plugs. Oh, well.
For those that dyno your car regularly, do spark plugs really make a difference?