.028 plug gap??

[AZ_IceMan]

good stuff[?] Also, the O2 housing you bought was for a PT or SRT? let me know how it fits [^]

[rszappa1]

As a turbo lite owner...I have never seen an engine with so many different spark plug setting...from 28 to 52....

[AZ_IceMan]

Well yeah, originally the factory wanted like a .050 gap with the stock champion coppers and now there is a TSB that supercedes this with NGK coppers with a gap of .045. If you start modding your engine then you will need a better spark and so your gap needs to go down a bit. I personally run mine at .033 with all my mods i have. Gives me great low end and high end with no predetonation or misfires. Gotta remember, i am far from stock though.[8)]

quote:Originally posted by rszappa1

As a turbo lite owner...I have never seen an engine with so many different spark plug setting...from 28 to 52....

[Topless in Cali]

quote:Originally posted by AZ_IceMan

good stuff[?] Also, the O2 housing you bought was for a PT or SRT? let me know how it fits [^]

I emailed E.D. about the o2 housing before I bid on it. They said it fits perfedt on the PT. I don't think there is any difference in the stock exhaust manifold/turbo set up between the PT and srt4. It's the downpipe that is a little different. I just hope their cat is cali complaiant! I didn't ask about that one.

[Mojito]

quote:Originally posted by AZ_IceMan

I personally run mine at .033 with all my mods i have. Gives me great low end and high end with no predetonation or misfires. Gotta remember, i am far from stock though.[8)]

How can a narrower gap prevent predetonation? If the electrodes are closer to each other that means the spark is more likely to appear sooner. Also with too narrow a gap the spark is smaller and thinner which decreases its ignition properties. Sorry, I don't know much about plugs and engineering, but it just seems illogical.

[Cal Cruzer]

quote:How can a narrower gap prevent predetonation? If the electrodes are closer to each other that means the spark is more likely to appear sooner.

Predetonation is not a function of the sparkplug's spark, it is more a result of a lean condition or hot spots or high compression.

quote:Also with too narrow a gap the spark is smaller and thinner which decreases its ignition properties. Sorry, I don't know much about plugs and engineering, but it just seems illogical.

We close down the gap because in a boosted environment plugs spark can suffer from "blowout". Closing up the gap helps this symptom somewhat. This is a pretty well know trick. While an NA engine would not really benefit from this, it works well on boosted cars, especially with greater than stock boost, but it also helped my with no boost enhancers before I got Stage 1.

[Topless in Cali]

I regapped my Denso's ITV16's to .033 and that does seem perfect, AZ! Thanks for doing all gap testing. It really starts quicker now, even when cold. I thought for $10 I'd try the Mopar S1 recommended plugs at the .035 recommended gap, FOR ****! I'm now throughly convinced that the Iridium plugs are way better than copper or that it could be that they just don't sit into the head as far blocking flow. Whatever is the reason, even my wife could tell the difference, especially over 15psi. I think I'm going to go with the Denso ITV20 or 22's. 1 and 2 steps colder than stock respectively. I'm just sold on the shorter, iridium plugs. If anyone in So Cal wants the new NGK plugs, $5, you pick up.

[AZ_IceMan]

I'm glad they worked out for you. I have the copper ones, not really sure about upgrading to iridiums. They will work fine, just gonna spend a little more cash when not needed. But anyhow, if you all have anymore questions, feel free to ask. Until then, happy cruising.