I'm assuming since my APS TT kit didn't come with spark plugs that the stockers are just fine. Only problem is my stockers already have almost 40K miles on them and I'd like to replace them.

Should I just get a set of stock replacement platinums or go with something else? Maybe a cooler heat range? What spark plus are the rest of you guy running with FI?

 

NGK Iridium: LFR6AIX-11 (one step colder) at: www.vividracing.com Good price and service!

 

I've run both copper and iridium since going FI (both 1-step colder). Absolutely no difference in performance or longevity. Buy what you want, but IMO no point in spending extra on iridium. Definitely go 1-step colder, tho.

 

We've always run the NGK Iridum one step colder than stock. No complaints at all. Iridium tends to hold up to heat better than coopers as well.

We always carry about 10 sets in stock: http://www.forgedinternals.com/store...cat=264&page=1

 

It was my experiance that the iridums are less prone to spark blow out at the same gap versus the coppers.

 

My installer recommended I use stock for my APS ST. I don't know what to do? Why 1 step colder, does it help performance?

 

One step colder is for additional safety.

The APS manual states to use one step colder plugs for my environment. I will do what they say since they engineered the thing. I got my Iridiums from Sharif.

 

I also use the NGK Iridium 1 step colder spark plugs.

 

I use IKH 20 for 100shot nitrous

 

So for hotter climates it's recommended? Can't get much hotter than Vegas. For safety: that means less likely to damage the engine?

 

Stick with the one stage cooler you will be very happy with them NGK LFR6A1X11 let me know if you need any.

 

Yup, Im using the NGK Iridium 1-step's as well.

 

+1

 

does anyone have the copper plug part number? 1 and 2 steps colder than stock?

 

I do not believe these plugs can be found in copper or even platinum. I've looked and looked.

Tuan

 

Also so am I, um to the starter of the thread... Kinda "Boosting" 101 (using colder plugs)

 

Thanks for all the replies guys! I guess I'll be going with 1 step colder iridium plugs.

 

Sure they can. I'm running copper now with my Vortech. I ran Copper 1-step colder when we first installed it. Switched to Iridium 1-step colder at 10K miles with Vortech. At 20K miles with Vortech, I switched **back** to copper 1-step colder because under FI application there was no discernable difference in performance or wear between the copper plugs I pulled out 10K miles and the Iridium I pulled out at 20K miles.

A search on this forum should yield the correct NGK Copper plug part #. I'll try to remember to post it after I get home tonight.

 

LFR6A-11 is the part number for the copper plugs. I was thinking in the 7 heat range . They don't make copper in the 7 . I didn't think about the heat range numbers when I made the original post. Now if someone can find me double platinums for the Z in the 7 heat range that would be great!

Tuan

 

Thanks for the order Brian...they shipped today. Tracking info has already been emailed to you.