NGK BPR6ES in mine.

All eight of 'em. Time to put in some new ones too!

 

ive had good luck with cheapo autolite 64 plugs from wal mart

 

Looks half empty to me.

 

Back from the dead.. Don't suppose you know the PN you're running do you? The stores in my area are complete retards and keep giving me the wrong heat range plugs so when I swap to Iridiums I'd like to just give them the PN. Hard to screw that up (I'm sure they'll find a way).

 

No I do not.
You need to look them up yourself, I never go to the auto parts store and ask for a part, I always ask for a part number.
Look them up on the brands web site.
The AutoLite Iridiums I was running did not last very long.
The Denso's I ran prior lasted forever, the only reason I changed those out was because I was chasing a mis fire that turned out to be a bad plug wire.
The AutoLites lasted just over a year, I am now running cooper plugs.

 

No worries mate. Thought I'd ask. I'll track it down on the manufacture side like you suggested. I've learnt my lesson, never trust the parts counter.

 

I popped in Autolite 64 a few months back. I've been chasing my tail on a severe under load misfire which I thought was something falling apart in the driveline (the engine was the last thing on my mind). Stopped by my favorite indy LR shop, JC's British & 4x4, and Jeff figured out the misfire part. He checked through the cap, rotor, wires, and even pulled the plugs. Since they were out, he asked if I wanted him to put in the Denso plugs he prefers (p/n 3031 IIRC). I say what the hell, I was desperate for a solution. Presto - misfire gone. I was shocked. Jeff mentioned the gap looked large on the Autolites (and I didn't check them before installing - bad on me). He also mentioned he stopped using Autolites some time ago, due to a manufacturing mistake he kept running across - the metal body wasn't crimped tight enough around the ceramic body and the spark would come up between the two. While my plugs didn't have the tell-tale tracking you'd get from such an issue, there was something not right with them. I won't get them for the Disco ever again - I'm sold on the Densos.

 

No wonder you had a misfire. The Autolite 64's (what I usually use) are around .050 or .060 out of the box. D1 plugs should have a max gap of .038.

I don't know of any copper plug that comes pre-gapped.

 

The AutoLites I had wore really fast.
My truck would be running as smooth as the video shows, then it would start to stumble at a hot idle, pull the plugs, check the gap, to big.
Regap and then smooth as silk again.
Third time around they were worn to bad adn had to be junked.