I have a H/C, headers, z06 manifold, intake, pulleys etc...

What are the best plugs out there and then the second best...Also the best tools to buy to change them out. My first tool will be bandaids I need to start with buying the plugs first though...I need brand and part number or what ever I need to pick them out too. Thanks guys!

 

NGK TR55's. I have virtually the same mods and they work great. My tuner swears by them.

 

What gaps should I use?

 

The iridium NGK TR55IX comes pre-gapped at the factory, and you're not supposed to change it.

You'll need a 3/8" ratchet, 4" extension and 5/8" plug socket.

Check out this thread.

http://forums.corvetteforum.com/show....php?t=1332052

 

NGK Tr55s are the best plugs to get for any C5!

 

 

There's 4 or 5 different NGK TR55's...some can be regapped and others not depending on the metal that was used. So are the more expensive TR55's worth it or just use the base model ones?

 

A universal joint makes it easier to get hard plug out.

 

The new GM spec calls for iridiums. I called the dealership and confirmed that point.

Spark Plug: Technical Service Bulletins Ignition System - New Spark Plug Type/Gapping
Bulletin No.: 03-06-04-060
Date: October 24, 2003
INFORMATION
Subject:
Information on New Spark Plugs and Gapping
Models:
2004 Buick Ranier
2002-2004 Cadillac Escalade, Escalade EXT
2003-2004 Cadillac Escalade ESV 2004 Cadillac CTS-V
1997-2004 Chevrolet Corvette
1998-2002 Chevrolet Camaro
1999-2004 Chevrolet Silverado
2000-2004 Chevrolet Suburban, Tahoe
2002-2004 Chevrolet Avalanche
2003-2004 Chevrolet Express, TrailBlazer
1999-2004 CMC Sierra
2000-2004 CMC Yukon, Yukon XL
2001-2004 CMC Yukon Denali, Yukon XL Denali
2002-2004 CMC Sierra Denali
2003-2004 CMC Envoy XL
1998-2002 Pontiac Firebird
2004 Pontiac GTO
2003-2004 Hummer H2
with 4.8L, 5.3L, 5.7L or 6.0L V-8 Engine (VINs V, P, T, Z, G, S, N, U - RPOs LR4, LM4, LM7, L59, LSI, LS6, LQ9, LQ4)
A new spark plug has been released for use in the above vehicles. The new spark plug has an Iridium tip instead of the current Platinum tip. Due to the different tip design, the gap of the spark plug has also changed. The new spark plug, P/N 12571164 with AC Delco P/N 41-985, is gapped to 1.01 mm (0.040 inches) when the spark plug is made. The spark plug gap is set during manufacturing and should not be changed or damage to the spark plug may result. Any new spark plug found to not be properly gapped should not be used.

 

I find .050 works best on stock to mildly modded LS1s. The higher gaps don't seem to provide as good throttle response.

 

I did a search, and found the ACDelco Iridium Plugs mentioned above for $49.15 shipped (8ea.) from GM Parts Direct
Is this a good price, or has anybody seen them at a better price?
Thanks!
-Goose

 

As I recall when I bought mine, that is a very good price..........think I paid about $7 each.......... delco iridiums.

 

The website says GM List is $8.18 ea. GM Parts Direct has them for $4.90 ea.

 

The iridium NGK TR55IX are the best

 

The problem I see is that they come pre-gapped at .060 and are at least 7 bucks each.
Now, why the difference in gap from one brand to the other for the same engine? Wouldn't having a different gap affect performance?
Just curious if someone here can explain what gap would produce the best performance, if installed on a stock LS6 engine.
-Goose

 

I just put the TR55's in my '04 Z06 gapped at 0.60 and after a 1,000 mile trip I had no issues at all. The car ran fine. Alot cheaper than the IX's for sure. 21st Century Musclecar is running them in their new '06 Z06.
I'm going to try them at 0.42 and see what happens.