00 N20 T/A

I finally got my turbo kit installed this weekend. Runs great except for one thing. It misfires when it starts to see boost. Im thinking the plug gap is wrong I gapped the plugs at .055 is that too much? BTW the plugs are NGK TR6's

Spade

iTrader: (26)

Most boosted people run a .035 gap for there applications. I would think a .055 is to much. I am boosted and run a TR6 at .035 so it has to be right. The TR6's come gapped at .035 as well.

edit: ment .035 not .35

EPP

iTrader: (22)

Yes indeed, go with .035, as you will blow out the flame with a wider gap. Bob

00 N20 T/A

thanks for the replys guys. I am gonna regap them today and see what it does

tamanjd

iTrader: (1)

.035 is what I am running on mine with 5psi and I am running the tr6 plugs as well.

white2001s10

iTrader: (4)

You want to find out what's causing your problem instead of regapping plugs to cover it up. Yes .035" gap is better, but still find out what the problem is.
Pretty much you're either too lean or way too rich.
Check it with a wideband and reproduce the problem.
Fix the problem, then regap your plugs.
If you don't, you're asking for trouble.

Dragframe

iTrader: (14)

the problem could be that with that big of a gap he is blowing out the flame

which you may then ay get stronger coils and blah blah.... but why do people gap their plugs to .035 when they boost or spray (or more compression..)?? because it will miss because the extra pressure puts the sprak out.


Someone correct me if wrong.

BlackHawk

iTrader: (2)

Yes that gap is way to wide.
I run my TR6's a little tighter than the .35 that they come, I like to close them up to about .33-.34 my car just seems to like them better that way :shrug: . I'm running a little over 10psi right now.
Of course that bad plug set up would be a likely culprit to your misfire and you could be blowing out the flame... But what have you done about the tune? Also make sure that you have enough fuel pressure. Your car will start to stumble when you get into boost if you don't have the ability to feed it enought fuel. Make sure that your secondary fuel pump is working. You can cause major damage if you run it too hard and too lean.

Schantin

iTrader: (6)

The car will also stumble if getting TOO MUCH fuel. My initial tune was way too rich, and had the same problem. I was richer than a 10 to 1 ratio. My friend leaned the injectors out for an 11.4 to 1 A/F ratio at WOT and now things are happy.

BTW, my TR6's are also gapped at .35. I'd change that 1st and go from there. Just my $0.02

white2001s10

iTrader: (4)

I'm repeating in hopes it will be read again.

If you were too lean, then you will misfire sooner and more often with wider gaps.

Tightening the gaps will reduce the misfires, but not fix the problem. In fact the misfires may be saving you from engine damage.
It's always best to find out what is causing the misfire first.

When the A/F is right, then you may get misfires from a weak spark, but usually not enough to notice a significant change. A too lean or too rich condition causing the misfire does show a very noticable change in power.

When the A/F problem is resolved, then you tighten the gaps to reduce the few misfires left and gain a slight bit of power in the process.

Wide gaps are extremely handy for getting your A/F where the engine wants it. Tighter gaps reduce misfires, make more power, and keep the ground electrode cooler.

I'd bet there are very few people on the planet who's engine actually "blows out" the spark. In most cases you'll find a lean misfire, or overheated electrode, or fuel washing the insulator.

00 N20 T/A

I did change the gap and it fixed the problem. But I notice when the car is at idle that I can smell raw gas coming out of the exhaust. The guy I bought the kit from had a re-flashed comp from Nelson Performance. I have never heard of them. Honestly I am prety dissapointed in the performance of my STS kit. I am only running 5psi of boost and it doesnt feel that much faster than before I put the kit on..

JAvenger007

iTrader: (9)

i would check into that tune. keep it safe and figure out your a/f to make some more power. If you already had those pacesetters and full exhaust along with that stall then your probably only seeing a 40-50 hp difference with that sts kit on that current tune. So thats likely why the turbo addition doesnt feel like such a seam of the pants difference

white2001s10

iTrader: (4)

Your number one priority is getting a wideband on it to see what is happening. Smelling fuel in the exhaust can be a sign of lean misfire, or way too rich, and either condition causes misfires and can lead to engine damage.
No one with a turbo should be without a very good wideband and a way to log the data.

00 N20 T/A

What would you recommend for a wide band? I can get a brand new innovative LM-1 for $275 are they any good?

Schantin

iTrader: (6)

Sounds too rich. That's how mine was initially. Any engine codes? I had a crank position relearn on my "new" PCM that screwed things up too. After that my car smelled like gas (aka running too rich, not lean) and would stumble when going to WOT. Felt sluggish and unimpressive too. My AEM widebans said the A/F was 10. to 1 at WOT. It was really like 9 to 1. I had a friend program the PCM to decrease fuel at WOT... and gained at least 50HP in the process. Now the car feels pretty good.

So, you need to take the car to a reputable shop or have a friend with HP tuners/ EFI Live / Ls1Edit or similiar that knows what he's doing make the adjustments for you. This is part of the process of setting up the turbo. Don't be disappointed. Get the tuning straight and you'll have nothing but grins from the boost.

white2001s10

iTrader: (4)

That's exactly what I use. I've never had a problem with it.