Spark plug life

Just curious as to what this gang thinks about plug life. How many runs, or time?

I have a about 100 passes in two years on mine and probably should change them, but see no real reason. We are going mid 10's on a big block and they look fine.


What do you think?

Tom...How old and what kind of plug wires are you using?

My NGK's were installed in the fall of 2015. I have maybe 100 street miles and about 150-200 passes. The car starts fine, idles clean and my et's don't fluctuate. When I detect a slight miss at idle or the car seems to load up at start up is when I change mine.

Good point. Accel super stock. I'll wring them out to see what kind of ohms I have.

I don't remember how old. hummm

4th race season for my ar3911’s and my ultra40 wires. Might put a new set over the winter if I rebuild the engine

What ignition and plug gap?
My thoughts are if it ain't broken, don't fix it
I use to change plugs at the track after every race, I would leave the old ones in it to warm the car up in the pits and then put the new ones in
I had cans of spark plugs that had from 10 to 16 runs on them
Once I switched to the MSD race gold ignition boxes and their matching coil I didn't need to do that anymore

I'm on this program, change plugs when i rebuild the engine every 400-500 runs. There's 16 of them!

MSD digital 6AL, .035 on the plug gap

I see a lot of folks like Cab used to do, changing plugs all the time, and it just gets one to thinking.

I'm going to change these, but not because they need it. Because I have them out.

Many 100 run seasons. Still ET/MPH the same as when they were new.
Doug

Depends on the plug and how it was designed. I'd much rather use an easy to fire, much fewer run plug than use something that is designed to go 50 or 100k miles. Plugs are cheap.

An old Mopar mechanic 40 years ago told me after I had issues with Champion plugs to throw them in the trash, buy some Autolite plugs, gap them at .028-.030, put them in and go race. Still doing it, still working good.

I typically get two years out of mine.....I keep running them if the electrode holds up....

I run autolites ar3911 change out at the beginning of the season just for the heck of it. But for $30 once a year why not.
Just had a $50 coil go bad and quit without warning, around 5 yrs old for it.
changing out the inexpensive parts every so often might not be a bad idea.

Anybody out there using the E - 3 plugs? the pro guys claim they use them, probably just for advertising purposes.
Thought about trying them but are they worth the price? ive had good luck using NGK race plugs and autolite.....

I used to run them a long time in my cuda...at least a year or more. No reason to change them all the time. I use NGK plugs and MSD 6AL boxes on all my cars. Plug wires vary, never had a set that didn't run good, some just fit much better than others.

The E3 plugs are a joke...along w/ every other "revolutionary" plug design. There's so much snake oil in the ignition products market it's ridiculous...plugs AND wires. There a lot of gimmick parts out there, but the ignition system market seems to be saturated with them. Maybe I shouldn't say "gimmick", but a lot that work fine, just never live up to their hype.

I had 4 Drag weeks on my AR3911s, when I put my new motor in I forgot to buy plugs so I took the ones from my 360 and moved them to the 416. So four drag weeks with two motors haha. They still looked good but started to show a little wear, and I just freshened up the top end so I changed them out.

I use a dental 10X magnifeyer to look at my plugs closely,, I do replace them when the center ground electrode gets rounded off from wear or it is wearing on a angle to the ground strap
I do see what looks like slag or metal hanging off to one side of the center electrode also when the motor is to lean making the plugs do that
Get a good magnifer to help you get a good close look at your plugs and then decide

How can you call it a "race engine" and leave plugs in for so long?? LOL

Plugs tell you all about whats going on in there...

Run some nitrous , and you will go through a lot of plugs...LOL

I usually change the plugs whenever I freshen the motor up after 400ish passes. I run autolites in my cars.

I switch to E85 5 yrs ago, that stupid fuel seems to be VERY sensitive to the plug heat range, but that being said I ended up switching motor parts which led to R&D problems in the valve train that I may have interpreted as spark plug problems. Same deal on the new motor with a goofy distributors and some bad ignition parts, I hate motor problems(race car or any other vehicle problems)
Time to take a step back and really focus on this rascal to get rid of those type problems