Another Iridium Thread...

[raz0r$harP.UK]

I've currently got some unknown (brand and heat range) platinums that were gapped to 0.8mm. Due to a poor tune I need to replace them before the retune. Been looking up the spark plug threads and I'm going to give the iridiums a shot.

~200kw RB25 so I've got my eyes set on the Denso IK20s or the NGK BKR6EIX(one heat range colder than recommended for GTS25t, and standard recommendations for GTT). Seems that most people have NGKs, I doubt there'd be much difference but interested in any comments from someone who has the Densos.

The NGK I've listed has a 0.8mm gap standard, whereas the Denso is 1.1mm - but I've read that due to the narrower centre electrode in the iridiums (NGK Iridiums have a 0.6mm centre opposed to the Denso 0.4mm) - a larger gap (hence better spark) should be possible with the Denso. Thoughts? Or should I just gap the Densos to 0.8mm?

Cheers

[Robo's]

I dont think 0.2mm is going to make any difference into the quality of the spark considering copper plugs tips are 2.5mm. I tried my iridiums at the standard 1.1mm and it misfired running 20psi. I had to bring the gap down to .85 to stop the miss. I tried .9 and it still had a slight miss

[ZILR-34]

im using NGK Iridiums that have a gap of 0.6mm, running 20psi and hasnt missed a beat yet. anything higher than 0.8+ will miss fire on higher boost, and wont be able to run high boost levels

[4doors13secs]

hey pplz...i just bought some spark plugs(NGK iridium BKR6EIX) and i've been reading abit about .8 and 1.1 gapped plugs, the guy at autobarn said they were gapped at .6 so i was just wondering if that is suitable for my nearly stock RB25DET running 7 and 10 psi...i've search and cant really find exactly what i want to know...

please PM if it's no trouble...thank you

Edited July 17, 2008 by 4doors13secs

[DECIM8]

0.6 is not a common gap, check the packet or get them measured.

Id say they are 0.8. You want as big a gap as you can get without misfire, this is often found to be 0.8 in boosted vehicles.

[TTT]

what are you reasons for choosing iridium over the superior and cheaper copper?