I don't know much about spark plugs but I do have common sense. Some people put colder plugs in with stage II. GM says it is not needed so I never changed plugs. I only have 8k miles on my car so I don't need to do a tune up yet. However with the following mods and changing to a 2.9 pulley from Nate do I need to worry about changing spark plugs? Should I wait until I go get tuned and see what they tell me? I'm not worried about heat cuz I'll have dual pass and CA H/E which should be plenty enough for a 2.9. Thanks guys. Please tell me why if you do give me info. I would like to know the reason behind the one or two step colder plugs. Also why copper or some other material.

Mods:

GM Stage II tune
2.9 pulley
Injen CAI
GMP manifold/header
ZZP downpipe with Highflow cat
GMP Touring Exhaust
TTR Engine Mount
TTR Tranny Bushings
Exedy Clutch/flywheel
Stage II Drive Shop Axles
CA H/E
GMP Dual Pass
+ mods in my sig

Future Plans: polished (not ported) supercharger, polished throttle body, dyno tune

 

I would also like to know about the step colder plugs....i put them in my car cuz alot of people on here said that i should run them with the stage 2

 

Colder plugs help reduce knock by reducing cylinder temps.

http://www.ngk.com/charglossary.asp?kw=Heat+range

this will help you

 

Yea exactly, I mean just because other do it does not mean its a good thing. I have yet to see or read exactly why you would need a step colder. Sometimes common things people do to their cars is not always a "good thing" Thats why I want to know why or if I should run differant spark plugs with my mods and a 2.9 pulley.

Thanks! +rep

 

when you run a smaller pulley the car tends to knock or denonate.. going a step or two colder helps just a lil when running the smaller pulleys

 

I have been running the ngk plugs and a 2.9" for a while and it runs excellent. I do not have anything to measure knock but it runs good as far as I can tell. I just put new ngks in it last weekend and the old ones were nice and choc. brown. Mine were gapped to about .037-.038ish because it didn't like the .040 gap.

 

IMO You should use a 1 step colder heat range. Also I think they use copper because of its ability to transfer heat. And they use IR for its ability to withstand a beating due to its hardness.

 

I will have to check into those plugs once I install my 2.9. Some guys talk about copper plugs.

 

USE YOUR STOCK PLUGS WITH YOUR SETUP!

Listen to people that actually know what they're talking about not people that read crap on the internet and swear they're an oracle. Ask anyone thats has actual first hand knowledge with this car and you'll find that stockers work the best with what you have.

 

I used the NGK BK7RE 1 step colder. Just get the copper plugs. They were $10 for the set. I gapped them at .40. Car ran great. Much smoother at idle than with stockers.
I had been running Stage 2 and 2.9 as well.

 

The ngks I have are copper. They are like 2 bucks a piece, can't beat that.

 

The colder plugs reduce the chances of detonation (read: knock) in high-boost applications. The engine will run better and smoother... especially when hot. On Stage 2 or 2.9" the car will run with the stock plugs in it. But it will run better with the colder ones.

They cost like $2 a piece... it's really the cheapest thing you can do to make the car run better.

 

Do yourself a favor and get a set of ZEX plugs, you will have 0 issues! I have had stock plugs, 2 sets of NGk BKR7E's gapped at different gaps, and the ZEX plugs.

The ZEX are the best by far and you dont need to gap them, made a big difference!

And yes when you add boost or go down pully sizes you must regap the plugs, you can get away with using stock plugs with stage 2 but it doesnt work as well

 

this is why i suggest just reading hehe.
lots of people have some very curious opinions.

mine is that every car is different, give your car what it wants.
do not listen to people on which plug or which gap will work in YOUR car.

and NEVER trust factory gapping.
try the plug you believe will help you....then try at LEAST 3 different gaps, to see how your car likes it.
Id suggest trying 0.40, 0.37 and 0.35 just to see what the car prefers.

theres 1 rule of thumb. you want the biggest gap your car can safely handle, without any misfiring or blowout.
ONLY go smaller if the car demands it.