How to fix terrible ign timing (without increasing octane)

[ZyroXZ2]

I think the Densos have some questionable quality. I bought a set from BMS, and while I'm sure these would have worked in my car "fine", I still didn't feel comfortable installing these four out of the 6. I wish I had inspected them before gapping them, but it wasn't UNTIL I was gapping them that I noticed some crooked electrode tips and some inconsistent welding around them. One even had a tiny little spur sticking off of it!






BMS denied any returns and said that they've sold plenty of these, so apparently that means my set isn't a problem. I ate the $60+shipping and just tossed all of them.

 

[Toddasaurus]

Dang... Interesting.

I got new OEM plugs and regapped to 0.026" and slightly trimmed the ground straps to further reduce shadowing before installing my JB4. Currently running an intake, midpipes, and cat-back exhaust, and map 6 (set very similar to map 2) and it runs very strong. Super smooth idle and haven't had any problems so far, and I often drive like a total jackass.

I think a lot of people mistakingly underrate the stock plugs.

 

[lun471k]

Dang... Interesting.

I got new OEM plugs and regapped to 0.026" and slightly trimmed the ground straps to further reduce shadowing before installing my JB4. Currently running an intake, midpipes, and cat-back exhaust, and map 6 (set very similar to map 2) and it runs very strong. Super smooth idle and haven't had any problems so far, and I often drive like a total jackass.

I think a lot of people mistakingly underrate the stock plugs.

I'm curious to know if people had trouble at all with regapped stock plugs. Never heard anything about it.

 

[Terry@BMS]

I've seen tips like that damaged during gapping, but for ungapped new plugs tips should all be straight.

 

[cncBilly]

I'm curious to know if people had trouble at all with regapped stock plugs. Never heard anything about it.

There has been a few non stock cars on here than have blown them.

 

[Toddasaurus]

There has been a few non stock cars on here than have blown them.

There's a chance they were probably defective to begin with, or even poorly gapped. I've also seen other people end up having problems with properly gapped Denso's (ie CEL's, horrible idle, and power loss during WOT). Even so, I can see the stock heat range being a problem when running map 3 or map 5 and constantly driving super hard. I'm thinking WMI would solve the potential heat problem in and of itself.

I planning on pulling mine pretty soon to see how they are holding up.

 

[ZyroXZ2]

I've seen tips like that damaged during gapping, but for ungapped new plugs tips should all be straight.

Nice try: I use the same gapping tool you sell. The electrode tip is never touched. Like most, I didn't actually look at or near the tip until I'm looking at the gap, and that's when I noticed four of the six I bought from you all looked like this. I took pictures, and sent them to you all, and you all just gave me the proverbial middle finger acting as if because there are thousands that are fine, these are fine to put in my car.

Sure, I only ate $60+shipping, but that kind of customer service terrifies me. I am more than sure I made the right call to toss these. Besides, you can tell from these pics that the tip was never touched. If it was, you'd see evidence of cracking or bending. These are just poor quality spark plugs that have their tips welded off center and crooked, and in once case, that tiny little spur coming off the weld (which can become a problematic spark point under heavy heat/loads). Only two of the six I bought had perfectly centered/straight tips.

 

[Terry@BMS]

Most of the ones I've seen are straight tips but if that is how you received them from us then that is how Denso sells them. Rarely do we have any issues reported with them but a spur would certainly be cause for concern and need to be removed. Our support guys aren't going to know much about plugs as we're just reselling them and once they've been gapped we generally can't take them back for obvious reasons. Sorry you felt you had to eat 4 plugs, we can always do a store credit for you next time you need something.

 

[Toddasaurus]

Pulled my plugs the other day to see how they're holding up...





The center and ground electrodes look very clean, not being fried by excessive heat so far. The color on the threads is from my copper based anti-seize. It gets that way after being heat cycled.

I installed brand new OEM plugs when I put in my JB4. I trimmed the ground straps (both narrower and shorter) to reduce shadowing. I also gapped them to 0.026". I chose to use the OEM plug because it features a projected tip, unlike the Denso's or the HKS plugs, which should aid in better combustion. The only downside, on my opinion, is the heat range. But so far they're holding up well, it seems. But it's only been about 3,000 miles. Even so, I'm confident they have a ton more life in them. NGK makes really good plugs.

Mods are: JB4 Map 2, 92 octane gas. AEM intake. ARK midpipes. Magnaflow exhaust. VT snorkels, and SXTHElement dual catch cans.

 

[Revvdmedia]

Those electrodes look consistently better quality than many of the Denso's I've touched with my hands this year....

Maybe if I feel the need to change plugs, Denso's are not the way.

 

[turboAWD]

What anti-seize do you recommend for plugs? Is it necessary? I did the plugs in my Subaru boxer 3-4 times, and a total PITA, and still never had any issues without anti-seize. I have Permatex anti-seize lubricant - usable, or not rated for high enough temps?

Can you explain trimming the ground straps more?

 

[Bigbikes]

I think the Densos have some questionable quality. I bought a set from BMS, and while I'm sure these would have worked in my car "fine", I still didn't feel comfortable installing these four out of the 6. I wish I had inspected them before gapping them, but it wasn't UNTIL I was gapping them that I noticed some crooked electrode tips and some inconsistent welding around them. One even had a tiny little spur sticking off of it!
Crappy






BMS denied any returns and said that they've sold plenty of these, so apparently that means my set isn't a problem. I ate the $60+shipping and just tossed all of them.

 

[Toddasaurus]

What anti-seize do you recommend for plugs? Is it necessary? I did the plugs in my Subaru boxer 3-4 times, and a total PITA, and still never had any issues without anti-seize. I have Permatex anti-seize lubricant - usable, or not rated for high enough temps?

Can you explain trimming the ground straps more?

Anti-seize isn't needed, but it's just one of those things that's nice to have as it makes removing stuff a little easier down the road. Supposedly copper based anti-seize also helps with heat transfer; but I'm sure whatever impact is negligible at best.

Trimming ground straps is an old school practice, similar to indexing your plugs. Though indexing won't make any difference one our engines since the plugs are centered in the combustion chamber and they're not coming in at angle relative to the combustion chamber.

All 3 plugs available for our engines already have a trimmed ground strap/electrode. If you look at the end of it, notice how it's not square, but instead has sort of a V shape? You can trim it even more by making that V a little more narrow, then trim it back to it's not covering the center electrode quite as much. My trimming was minimal, but some people trim it way back, which, I think would make things worse in turbo motors because it would really just be increasing the gap.

Hope that makes sense.

 

[turboAWD]

Thanks, that helps explain it quite well.