leading spark plug color vs trailing color
 

I just pulled my plugs out tonight to prepare for a MSD install. These plugs are about 1.5 years old, and have about 13K miles of normal driving on them, with periodic cleaning.

This is the first time I noticed that the trailing plugs looked like this. The leadings (two on the left) are always dark coffee brown/chocolate brown, but the trailings for the first time were showing half white half black (two on the right).

I just replaced the fuel filter recently less than 1K ago...and have not been driving it hard, boost at 10-11 psi, M2 ecu, walbro fuel pump, aeromotive fuel pressure regulator, apex SAFC, and the wide lambda on the dyno showed healthy, more rich A/F.

How important is the color on the trailings, and what color should they normally be in relation to the leading plugs? I'm not sure why the trailings would have two-tone colors.

http://members.shaw.ca/rotapowered/spark.jpg

Thats just about the same color I get, I think the darker area is carbon build up from running rich.

Yup, looks like mine when I brought them out.

Those look fine to me. I think from your picture you're running 4 x BUR9EQP, is that right? If you wanted to, you could try out one heat range colder on the trailings, but I don't really think it's needed. I would change them more than every 13k miles though. :)

The trailings usually look a little whiter or lighter brown than the leadings do. If they're ALL white or the majority is white, that's when I'd seriously be thinking about moving to a colder (higher number) plug.

As for the two tone appearance... I almost always have plugs look like that so I wouldn't sweat it.

My car isn't a daily driver, so I change my plugs about every 2k miles (once a year hehe). I run BUR9EQP leading, BR10EIX trailing. I have a single turbo and I think that combo works well on my car. Your car looks like it's about right on the plugs it has in it now.

They look normal to me, normal meaning that mine look about the same. I also have the m2 ecu. Let me know if you notice any diffrence in the car after you install the MSD. Im thinking of going that route.

it's normal to see WHITE color on the trailing plugs??? That's odd, as I've never seen this light of a color before. Anyhow, I'm gonna put in some new plugs, run some injector cleaner through the system, check the fuel filter lines, and see how things go.

Your being paranoid.

FDs will do that to you :D

they look alot like mine do also. for kicks once i indexed how they went in and they did have a darker side just like yours that faced the oil injector.

Man, those plugs are in bad shape. Lots of crud on the trailings. The color doesnt concern me so much as the worn down electrodes.....recommend replacing (or cleaning) plugs more often then every 1.5 yrs/13k miles :)

Color looks like mine after running for two months. Just got the 'ole wire brush out and went to work. Usually change mine at the most every 6 months.

Wow. I've always changed plugs around 2kmi on mine. I can't see someone getting more than 5-7kmi out of a set of plugs for the 13b-rew before carbon buildup and other factors cause a drop in power.

I'm trying to find out if Beru has a Silverstone plug that is equivalent to the NGKs that we run in our FDs. If they don't, i'm going to try and contact the U.S. distributor and ask him how we might be able to get someone at Beru to make us a Silverstone plug equivalent to the NGKs.

Why are you interested in silvertone plugs? If you are interested in trying differend brands or types of plugs you should visit my site. I have every known plugs detailed on my site that have been used in a 13B... or at least that I know of.

Have you tried Silverstones in anything? They are the best sparkplug i have ever used in anything.

We race high HP 2 stroke engines that put out about 287hp from a 1000cc, normally aspirated engine. To feed that kind of power in a 2 stroke you need TONS of fuel. To give you an idea, we use a 78mm carbuerator for each cylinder. Thats alot of fuel. More fuel than your average plug can handle. We've tried everything from NGKs, (varying heat ranges obviously) to Champions, to Denso Iridiums, to Boschs. Most of these plugs were pretty much on par with the rest of their respective counterparts. We could get maybe 1 race out of a set of plugs. Sometimes we wouldn't even get that far. While sitting at the line (we drag raced 500, 660 and 1320 feet) sometimes the bases would load up with fuel causing the plugs to foul. This happened no matter what plug we used.......except for one. The Beru Silverstone. The conductors are made of real silver, therefore the plugs are quite pricey, but these are the only plugs that we were able to go 1 full season on, and the only reason we pulled them out was because the portion of the plug that was exposed to the outside air was dirty and corroded. When we pulled the plugs after one whole season to swap them for another set, the electrodes looked in great shape and the plugs burnt any amount of fuel we threw at them. They even burnt raw fuel that was literally dumped into the combustion chamber when a reed valve (case reed inducted 2 stroke engine) was stuck open. Thats kind of like an injector being stuck open just dumping raw fuel into the combustion chamber. Try as we might, we just couldn't foul them. Now obviously i'm illustrating an extreme case but my point is that i think the Beru Silverstones might have an extraordinarily longer lifetime than any other plug on the market. Thats why i'm trying to get them for the FD. :)

Nice writeup and very interesting. Keep me/us posted on what they can offer. I read their site and one key feature is that they use silver. I'm currently testing BRISK plugs, which use silver as well.
cvs

The only Beru Silverstone plug in heat range 8 that looks like it will fit is part#120 001 070 accorind to http://www.nology.com/silver.html about the 7th plug down. It's 14mm, 3/4" reach, 13/16" hex the same as the ngk iridium BR9EIX plug. See if you can verify this.

No problem. I did not know the BRISK plug uses silver. There may be a slight difference in design between the Brisk and the Beru Silverstone. Who knows, the BRISK may even be a better plug than the Silverstone. I won't know until i try them both, although according to Bucrx7 they only come in heat range 8, and that does seem a bit on the warm side. They can probably be used though. I will try and get some more info on this :)

Bucrx7, thanks for the info. I tried speaking with a Nology/Beru representative but they weren't very knowledgable. I got more info from your post than i did from them. :)

Dont most people use 9s all around anyways?

Well, yes i suppose but here's the thing. 9s are colder than 8s you see and one thing we noticed with the Berus when we ran them was we were running a Beru that was in the 9 heat range, but they acted like an 8 compared to it's NGK equivalent. They burned MUCH hotter. Hell the Beru 8 heat range plugs burned like a BR7EQ from NGK. They were literally that hot. That would concern me.

Maybe after it cools down a bit here in Charlotte i will get my hands on some and run them.

Umm just wondering, isnt the higher the number the hotter? I guess Im wrong about this huh? So why is it good to run colder plugs all around (like the 9s). I use the NGK nines and I get about 2000 miles out of them (sometimes less) before I have to clean them again.

No. Higher the number, colder the plug is. Carbon buildup is normal on our plugs for most street going cars. If your car is running excessively rich, it could be due to a million reasons.

ForceFed,

Try the 8's in the leading position and maybe some normal NGK 9s in the trailing if you are worried about the heat range. The leading position is more important anyway and will yield more obvious results with a different plug. If you do give them a try be sure to let me know. I'll feature whatever you do on my site:)
cvs