plug gap for SC applications

[Stranger in the Black Sedan]

I searched but couldn't in a resaonable amount of time, find what plug gap to run for a 4.6 supercharged application. My brother and dad are ready to put the plugs in his Kenne Bell 4.6 DOHC and called me to see if the stock .052-.056 plug gap still applies to boosted. They are using the new plugs kenne bell recommended for the boosted application but they did not suggest any plug gap in particular

Thanks

Steve

[justbob]

I believe its .32. Let me check my book real quick.

[justbob]

Yep .032

I have AGSF 22C listed in my Trilogy book, but I went with the copper motorcraft crossed from that number.

[DOOM]

.32 is what i use. :up:

[ImpalaSlayer]

never changed the gap in my ngks.

[RR|Suki]

.32 is what I use too

[RR|Suki]

never changed the gap in my ngks.

I've had a package where 2 plugs were way off, maybe they got roughed up in shipping I dunno but makes me check every plug, every time.

[ImpalaSlayer]

I've had a package where 2 plugs were way off, maybe they got roughed up in shipping I dunno but makes me check every plug, every time.


i ment i never changed the gap in mine when i put the sc on. i checked them when i first installed them and gaped them to N/A specs.

[DOOM]

i ment i never changed the gap in mine when i put the sc on. i checked them when i first installed them and gaped them to N/A specs.

Change em to .32 and you'll be running 11's. :D

[ImpalaSlayer]

Change em to .32 and you'll be running 11's. :D


let me borrow your drags and ill runs 11s too :P

[RoyLPita]

I recall using .25-.26 on a Vortech application.

[RR|Suki]

let me borrow your drags and ill runs 11s too :P

Not with 113 mph :P

Car will run better if you go down from .52 or whatever stock is to .32 or so :beer:

[ImpalaSlayer]

Not with 113 mph :P

Car will run better if you go down from .52 or whatever stock is to .32 or so :beer:


define run better please. i wasnt being serious, after all i have LTS not shorties :lol:

[ctrlraven]

Dave if you are running the same NGK plugs as me then their pre-gapped to .035 already. Iridium plugs can not be re-gapped anyways.

[RR|Suki]

define run better please. i wasnt being serious, after all i have LTS not shorties :lol:

lol I thought as much, couldn't resist though

what I mean by run better is with less gap you'll make more power, less likely to have spark blow out/miss fires, less likely to have bad idle etc.

[ImpalaSlayer]

Dave if you are running the same NGK plugs as me then their pre-gapped to .035 already. Iridium plugs can not be re-gapped anyways.

yup same ones, look like im good to go then

[tjl006]

iridium can be gapped, my tuner did it when I got my car dynotuned, I had spark blow out problems. The gap had to be decreased.

[RR|Suki]

Dave if you are running the same NGK plugs as me then their pre-gapped to .035 already. Iridium plugs can not be re-gapped anyways.

That's good news for him, I was a little shocked that his car was running strong with .50+ gap.

PS you can gap iridiums

[FordNut]

You should gap the plugs as wide as possible, meaning as wide as you can without missing. You get a better burn with a wider gap.

That being said, with a boosted application you will commonly run into problems with missing due to spark blowout. This is caused in part by the higher cylinder pressures. The more boost the more the problem is seen.

So, for NA the gap is usually .050
For mild boost it can be from .030-.035
For higher boost .025
For really problematic setups .020

And yes, iridium plugs can be gapped. You just have to be very careful.

[Glenn]

I had several instances of blow-out running the SC MM. Had to go from 0.32 to 0.28 to cure it.

Glenn Ford :burnout:

[Stranger in the Black Sedan]

Oh yeah i forgot to mention this is for a twin screw, 9 psi intercooled setup. I'm not sure what is considered mild boost on these all aluminum dohc engines

Thanks

Steve

[babbage]

You should gap the plugs as wide as possible, meaning as wide as you can without missing. You get a better burn with a wider gap.


I've found that the GMS solid cop connectors let you run more gap than normal. I'm running .060 with no blowout N/A

[MM_BKK]

I'm running .028" on NGK TR7ix and KB Boost A Spark. Any wider gap and I get major spark blow outs. (They're NOT fun!)