Before the turbo, I still had the original plugs in it at 1200 miles and when I did the rebuild ( CP pistons and P&W crank, not wear issues) they looked new. Now I change them every spring but they looked great each time.
I installed a set of NGK Iridiums in my pickup over 100K ago; still going strong. I installed a set of Iridiums in my RZR as soon as I brought it home; they've made it over 2K miles with no problems. I'm expecting them to last a whole lot longer...........
I put 100k on original Autolites in my truck before changing. Yea the gap was a little wide (65 thousanths) but they still worked. I pulled my original RZR plug (NGK Iridium) at 1200 and it looked brand new. Changed it anyway but using the old one as a spare.
If your EFI is working properly, plugs should last a very long time!
I'm close to the same miles on the OE plugs and belt.
I have no plans to change the plugs. Almost all cars go 100k on plugs now days so I figure if I'm not running rich (over fueling) and not burning oil the plugs should out last the machine. I will look at them every few years just make sure. So for now I voted 5000 on more
Rebuilt primary clutch and replaced secondary, both worn out. Belt lasted longer than clutch. Mostly high speed desert travel. Lots of tires, no bearings, lots of grease, oh and a broken sway bar.
Are they platinum? I haven't looked at mine so I didn't vote . Back before unleaded fuel they would get dirty now days if your eingine is in good shape I would think they would be the least of your worry's? Has anyone changed them because they were bad?
I'm pulling mine after ~1100 miles to install a Weller Racing cam chain tensioner. Since its running well, I'll check the gap, anti-seize them and reinstall.
They were fine. Now at 1500 miles. Its fuel injected with electronic ignition and running unleaded fuel. If the NGK's don't last a long time I'll be surprised. Two new MR7F's as spares, though.
Just changed mine at 2900. The only reason I changed them was because I had a set in an oil change kit and I had the bed off to replace the throttle cable. Much, much better throttle response and acceleration, but like I said, I done the throttle cable at the same time.
Off topic, but check Your throttle cable adjustment. Mine had a lot of play and it or the plugs made a BIG difference.
In a perfect world, standard copper plugs will last about 30k miles before electrode wear and misfires become an issue. Especially so on boosted applications. Platinums and Iridiums can push the envelope to 100k+. I still don't like to push those beyond 60k anyway.
My RZR on the original plugs made it to about 750 miles until they got slight fouling from lots of cold starts and not allowing it to run. Caused cold running hesitation and misfires.
On my drag car, I would use standard coppers and change them out at least every other event.