first plug change 3RZ-FE @ 100,500 miles!

I replaced them with cheap Autolite copper cores from Wallyworld. When I get a decent air intake system, I'm putting Iridium in there and being done with it forever.
Crazy that this thing even ran. The gap was about .060 inch!
23+ mpg here I come hopefully

 

I've seen worse on less mileage, i'd opt for some NGK's or Denso over autolites though.

 

there's hardly any different in copper plugs FWIW. I'll change to a better plug in less than 10K miles anyhow, but for now these are far and beyond what was in there.
I was managing around 21mpg regardless. Just goes to prove that the coil on plug ignition system on the 3RZ is superb firing over that gap!

Platinum and Iridium last longer, but doesn't make your spark hotter. That's solely based on your ignition system, and evidently this thing is HOT!

 

Don't look too bad considering how long they were in there.