View Full Version : Sparkplug gurus chime in...I know you're out there

11-25-2006, 03:17 PM
Can someone read these and tell me what's going on....

Ok current setup:
S15 SR20det (10psi), FMIC, 3" catback, bov recirculated, high rpms, bkr7eix-11 gapped at .30

plugs have 1500 miles, car runs great, checked the plugs today just to make sure everything is snuff but i know jack about reading plugs other than noticing if one is fouled which none of mine are.

here's #1 cylinder


i think the timing is on and the ceramic is slightly speckled and the ring is sooty with some white soot in places. all plugs look very very similar.

here's something else that i'm not sure about....is the browning normal on the plug top?


thanks for the insight.

11-25-2006, 03:26 PM
looks good to me, after a few more miles, if you are getting the right mixture you will notice the center white part turning a good tan color.

11-25-2006, 03:33 PM
They look good and the timing mark looks right on. I don't see any signs from these pictures of detonation and the color looks pretty normal. When did you pull these plugs? You really need to pull them after a third or forth gear pull and shut it down right after the pull. Part throttle driving will usually burn the color off and so you can't get an accurate reading. I don't see anything signs of any problems from what I can see in these pictures.

11-25-2006, 03:42 PM
well the driving back to my neighborhood it's kind of hard to do a thrid/fourth gear pull. this was after a few hours of third gear pulls on some back roads. i figured they looked fine just wasn't sure about the browning at toward the tops. thanks guys

11-25-2006, 06:08 PM
Looks good. You're running a bit rich to keep the electrode brown the whole way, but that's not necessarily a bad thing if this was after a lot of WOT pulls. I run lean enough under cruise to remove a bit of that brownness at the base of the electrode.

12-07-2006, 05:48 PM
they look good however plugs can only give you a general state of engine. The way to "really" read plugs is to shut down where you want to to read the plugs..... for example to see your tune at WOT 6k, you would have to shut down at WOT 6k.


12-08-2006, 01:21 AM
my plugs don't even look like they've been run. that's how clean they are. i'll have to take a pic.

proper tuning > *

12-08-2006, 12:45 PM

So that browning by the lettering is normal?!?

12-08-2006, 12:49 PM

12-08-2006, 01:54 PM
my plugs don't even look like they've been run. that's how clean they are. i'll have to take a pic.

proper tuning > *

that's something I would like to see...

12-08-2006, 02:09 PM
my plugs don't even look like they've been run. that's how clean they are. i'll have to take a pic.

proper tuning > *

Uhhhh... I'm not sure what magic "tuning" you think would make it look like your plugs haven't ever been run. Proper tuning results in rich enough AFRs so that you turn the electrode tan, and a lean cruise will tend to make it a bit lighter lighter at the tip.

12-08-2006, 03:17 PM

As for the browning, I wouldn't worry about it too much. Just as long as you change them at recommended intervals, the 7's should work just fine for you.

12-08-2006, 03:24 PM
proper tuning > *

ha-ha I get it now. You put the asterisk as a wild card. I get it. fun-ey. ah hahaha. ahem. back to work.