freezeg35

iTrader: (3)

Im going to install 1 step colder plugs and gap at .30? when my vortech goes in. Im not too sure if i should use irridium or copper plugs. Also if anyone has a denso or ngk part number it would sure be appreciated. TIA

Z1 Performance

iTrader: (564)

Denso is only offered in 2 steps colder than stock for the Iridiums.

part number is IKH20

http://z1auto.com/prodmore.asp?model...ine&prodid=494

booger

iTrader: (6)

NKG iridium...L F R 6 R A L X -11 one step colder

CaneZMD

iTrader: (1)

That's what I'm running. (the NGK's above)

freezeg35

iTrader: (3)

is .30 a good gap?

joenismo

When I spoke to the Denso tech line they said that the IKH20 is one step colder and the IKH22 is two steps colder. I am running the IKH22(they are Irridium). NGK does not offer any two step colder plugs, only Greddy. The Greddy plugs are two steps colder and they are NGK, but NGK is a sister company to Trust, so NGK makes two steps colder plugs that are sold exclusively to Trust(which is Greddy). This is why I went with the Denso's because they were $13 a piece compared to Greddy at $22. If you try and purchase the Denso IKH22 at Autozone you need to give them the stock# which is 5345. Hope this helps.

etx

No need for iridium plugs, coppers are fine. .3 gap is fine, I would stick to something from .3-.35 for anything under 9 psi.

LOU

iTrader: (2)

Is there a difference in quality between the NGK and the Denso spark plugs?

Houston G35

I had 1 step colder copper plugs installed last week with my Vortech. I was told to change them every 12K to 15K or my performance would suffer greatly.

Questions:

1. Will I know when to change them by a performance drop?
2. Will waiting more than 15K run any risks to damaging the engine
3. Are there any plugs that I can use that will give me a longer time between changes. Its about 3 bills per change.

zcar03

iTrader: (7)

If I plan on running 9psi on my procharger, what should my gap be? NGK 1 step colder Iridium plugs

gersteinp

iTrader: (1)

There's another post regarding this in the FI section. Gap should be between 0.030 and 0.040 to prevent spark from blowing out under boost. Watch out for the extremely brittle central electrode in the Iridiums. My next set of plugs are going to be copper--way cheaper and probably just as good if you change them every 12K. If you don't change your plugs regularly, they can get fouled creating hot spots leading to detonation and the potential for a ruined engine.

zcar03

iTrader: (7)

So anywhere between .03 and .04 ??? I was looking for a more precise number. I have test pipes, will run NX nitrous 75HP, and 9psi pulley.

gersteinp

iTrader: (1)

I went with 0.035.

zcar03

iTrader: (7)

Thanks

mcduck

1. You won't notice a performance drop as such. They will simply degrade over time. What you will feel is an instant noticeable gain (well, reclamation really) of power you lost over the life of the old plugs

2. Not sure on that one, but I can say from experience my plugs lasted about 13K miles and were well in need of replacement when I changed them.

3. You can try Iridiums... they probably will last longer. Most recent discussion is that they are really no better or worse than copper plugs, though. Just be sure to go one step colder with either. Also, save yourself some cash and swap the plugs yourself. The hardest part with the Vortech is pulling the pipe with the MAF attached out of the way. With it removed, it's very easy to get to all 6 coil packs and plugs. Including the Vortech pipe removal/replacement, I was able to swap plugs in about 90 minutes total.

webcarconnection

What is the part # for the coppers, they are NGK?

Thanks!

captj3

iTrader: (1)

NGK PLFR6A-11 Gap .035 These are 1step colder.I'll be running them with my TT.
Good Luck

phunk

iTrader: (21)

i think that .030 is way too low for most people...

this car has coil on plug and I have yet to have any spark issues... oh yea that nice dyno graph i made last september (in my siganture link) ... that was on 35,000 mile old original spark plugs with stock gap... matter of fact at that point I had not yet even removed the plugs from my engine.

I recommend 1 heat range cooler and well I dunno I have been running .040 in a customers engine we recently built with no problems up to 9psi and 455rwhp so far.