How do these plugs look and am I getting spark blowout?

[Hiitman]

These are pics of my BPR8ES that were gapped at .026 and saw about 100 miles. I went back to BR7ES because I thought that the 8s were causing knock. But now I think I'm getting spark blowout. My wideband reads a steady 10.6 all the way up to 6200 and then both my front o2 and wideband start going nuts. The wideband jumps to 11.6 four times between 6200 and 6900. Lemme know what you guys think.

 

[turboglenn]

if it's blow out you'd know it, the car would shut down hard intermittently as soon as the boost is up and steady is when mine would do it. I turned out to be bad wires. I went through 3 sets of ACCELLs in one week, then bought Magnecore's and haven't had the problem since. Your plugs look like they are burning nice and clean. I think it's great how closed loop operation can keep a plug looking so nice and new compared to what carbs use to give us

 

[Hiitman]

So why do you think it's chopping up at the top end?

 

[eclipsegsx1736]

How much boost are you running?

Plugs look fine... .026" gap only carried me to maybe 25-26 psi. Anything above that needed a smaller gap. I'm currently running .024" gap, 30 psi with no blowout whatsoever. Haven't noticed any downside to running this gap, and have found many people that run the same gap as me or lower so it should be just fine. At high boost, the fuel won't have much trouble igniting due to the extreme heat and pressure in the combustion chamber, so it doesn't take much spark to ignite it at such high pressures.

I've turned my boost down to 15 psi or so for a couple weeks and I never changed the plug gap and didn't notice anything unusual.

 

[Hiitman]

So should I stick with the 7s or put the 8s back in? I'm running 23psi on the wg spring.

 

[turboglenn]

EclipseGSX also has a good point. Start with these 2 things...change the gap to what eclipsegsx recommended, then if you're still getting blow out try a set of good plug wires Those are the 2 most common and easiest things to fix that could be causing the spark to blow-out. Turn the boost down and make a pull and see if it still happens. If the car runs fine then you have isolated it down to either not enough spark energy in general or the wires not transferring all to the plugs or bad or incorrectly gapped plugs.

My car was shutting down from blow out at a measly 19 PSI on my big 16g because of the ACCEL wires not getting enough f the juice from the coils to the plugs.

Oh yea, and put the 8's back in, in NGK, the higher the # the cooler the plug,, so teh 7 is hotter and would contribute to knock easier than the 8's.

 

[eclipsegsx1736]

By the way, I have the MSD wires and mine are 3 years old and still work like a champ. I measured the resistance on them recently and it was around 50-80 ohms depending on the length. Damn good for any wire, especially for 3 years old. I'm using the BR7ES plugs (non projected tip, as opposed to the BPR7ES). I didn't notice any difference from these compared to the BPR7ES though. I've also had the BPR8ES and those worked but these 7's are working great so I've kept them in.

 

[Hiitman]

Ok. What's the downside to running too cold of a plug?

 

[Hiitman]

I talked to Mike at RRE and he said that running too cold of a plug could build up carbon and possibly ground the spark. That would only apply if you were running 9s or 10s on a dd. Full race or weekend beater would probably be ok for 9s. The coldness of the plugs has nothing to do with spark blowout. But he said that I'll have no problems with 8s with my setup. He also said that if I'm still getting blowout with like a .024 gap that I should probably get an ignition amplifier. Anyway. I hope that helped anybody that had the same question I did.

 

[Killa_dsm]

Thats some good info, I was having problems with my spark blowing out too. I think I'm going to decrease my spark gap and see if that helps. And Hiitman keep us updated on how it goes, and your results.

 

[Hiitman]

I'll have some results after tonight. If you have DSMLink you can look at my log and see spark blowout in full force. Really shuts down the car.

 

[Mikael SS]

I'm sure you're aware that the lower the number, the hotter the plug, right?

 

[Killa_dsm]

I'm sure you're aware that the lower the number, the hotter the plug, right?

WTF I don't get what or who your referring to in this post??? We are talking about spark plug gap, and no one said anything about running a lower number plug make it colder... ????

I'm pretty sure we all know a higher number means a colder plug...

 

[Hiitman]

No way!!! I never new that!! Thanks man I was totally confused about which was which...........


Anyway.
She's flying now. Minus the small ammounts of knock from my pos godspeed intercooler. Spearco here I come!

 

[Mikael SS]

WTF I don't get what or who your referring to in this post??? We are talking about spark plug gap, and no one said anything about running a lower number plug make it colder... ????

I'm pretty sure we all know a higher number means a colder plug...

I went back to BR7ES because I thought that the 8s were causing knock



Oh, so if i'm getting knock i should run a hotter plug? Good to know, i'll write that down.

 

[Killa_dsm]

I went back to BR7ES because I thought that the 8s were causing knock



Oh, so if i'm getting knock i should run a hotter plug? Good to know, i'll write that down.

Could you take your misinformation somewhere else. It doesn't look like you contributed much to this thread.

But anyways, maybe he meant he went from 8's to 7's because he thought they were too cold of a plug and fowling up??? And its always to try different things to see if it solves the problem.

 

[blcknspo0ln]

I'm just as confused as you guys are. Hiitman, can you post some 'pre' and 'post' spark blowout logs? I'd love to see that

 

[Mikael SS]

Could you take your misinformation somewhere else. It doesn't look like you contributed much to this thread.

But anyways, maybe he meant he went from 8's to 7's because he thought they were too cold of a plug and fowling up??? And its always to try different things to see if it solves the problem.

please point out what i've said that is not correct.

50% of the replies to any question are "search"

So if someone came through here on a search and read the first post, they would think that if they had a knock problems on 8's they should switch to 7's. Pretty terrible idea right there.

 

[Killa_dsm]

please point out what i've said that is not correct.

50% of the replies to any question are "search"

So if someone came through here on a search and read the first post, they would think that if they had a knock problems on 8's they should switch to 7's. Pretty terrible idea right there.

Oh, so if i'm getting knock i should run a hotter plug? Good to know, i'll write that down.

Well it doesn't look like your helping the problem either by what you posted. Since someone searching can take it the wrong way. Anyways back on topic, and sorry for cluttering the thread.

 

[Hiitman]

That log in the original post is my only good spark blow out log. You can see at about 6k where my o2 and wideband get choppy. Also where my timing curve starts to drop. I'll post some more recent logs that show no spark blowout later.

 

[Killa_dsm]

That log in the original post is my only good spark blow out log. You can see at about 6k where my o2 and wideband get choppy. Also where my timing curve starts to drop. I'll post some more recent logs that show no spark blowout later.

So you did end up fixing your spark blowout? Did you just gap your plugs down? What number plugs are you using now?

 

[Hiitman]

My old BR7ES were gapped at .028 and they were about 3-4k miles old. Now I'm using BPR8ES gapped at .026. But like Mike said, it's not necessarily the coldness as it is the gap. If your gapped at .020 and still get spark blowout then you need an ignition amplifier.

 

[Hiitman]

Here's a non spark blowout log from the next day. I'll post another next weekend when my spearco ic arrives