Plug Gaps changing on there own?

[Will_in_China]

Anybody heard of plug gap drifting?

The last three times I have pulled plugs, my plug gaps have appeared to have drifted wider... from 34 to around 43 a few times.

What the hell?
Knock causing it?
Eh?
ARGH!

-W

 

[100in6]

is it that the gap is opening or the post in the middle of the plug is burning down and is shorter? they don't just open up on their own unless they are wearing down making the gap bigger. how often do you change the plugs. one way of telling if they are wearing is if the post is rounded and not flat all the way across. what color are the plugs. do they look like they are too lean?

 

[bigtime]

Sounds lean to me. Get a magnifing glass and see what the electrode tip looks like. Take some good quality photos and post them. What plug are you using?

 

[Boosted]

Can't say I have heard about the plugs changing unless they are wearing away over time. Bear in mind that the higher cylinder pressures in turbo, supercharged and nitrous applications make it harder for the plug to fire, and result in a faster wear on the plug.

 

[Will_in_China]

Historically the plugs have been CR42TS but it has NGK UR4I's in it now...

I have changed them due to various elctrical problems (plug wire on downpipe twice, cracked ceramic, cap-n-rotor, etc...) every six months or so.

I hadn't even thought that the plug gap changing was due to electrode shrinkage!!!
Although I consistently run 950s on O2...
Yes, Wideband is on the way.


Austin did 'em for me this time as I was hungover as a mofo and he had all kinds of energy...

I will see where the hell they went and take some pics and stuff.

Once again, thanks for the input here...

-Will

 

[Sy769]

The KaBoom chip probably doesn't help matters.

I am suprised to see them wear that fast.

May pull mine soon to check them out.

 

[100in6]

next time try some, God i hate to say the word, autolites. l run them and have had the best luck of any plug.

 

[Will_in_China]

Autolites...
Somebody else mentioned denso's too.
Well, I will ride out the NGK's for now.
Truck is HAULING NUTS now, man I wonder how long this has been going on...
Anybody got a good article on plug gapping?

As for the kaboom chip, it only saw one pass in the ty on the previous set of plugs (first set, factory stockers).
Twin Turbo John took it back and gave it to the guy who bought my truck and he sold it with it!!!
Nats '03 was on a dig 20/20...

Weird either way, but the plugs are en-route and will be inspected for feedback...

-w

 

[rainmaker]

Hey Will is that a mis-type or are you really running NGK UR4I's? Did you go hotter cause you're up in Colorado?

 

[Christian Dionne]

I've had this happen to me in a supercharged LT1 with NGK TR55. It was years ago, but I think we just changed back to ACDelco and that solved it, although it could of been a bad batch of 8 NGK plugs.

It did feel good with the .050 gaps, but eventually probably helped lead to broken ring lands due to ignition miss under power.

My suggestion is stick with the known good plug numbers, and just give another set a try.

 

[Will_in_China]

They were the CR42TS, so they should have been ok, all three sets or at least one I would hope...

Didn't really notice a trend 'til now...

As for the 4's vs 5's or 6's, I need to look at the box, and since I won them at the nats, I threw them in just experimenting.
Will document!


-w

 

[AUSyTyIN]

They were UR-5's, and all of them were gapped to 42-43 except cylinder #4 (the one with the burnt wire) which was gapped to 47. Will, I hope you own a magnifing glass, cause I know I don't (unless the ones that McD's used to give out would work :roll: )