I'm putting in a fresh set of plugs, engine should go in tonight. NGK BKR7EIX Iridium plugs. I will be running from 1.2 to 1.5 bar of boost. Does around .26 gap sound about right?

 

I just put in some denso iridem tt s. At .022". The best it has ever run.

 

That's pretty tight. I'm going to go .025. I just damaged one of my new plugs though, the points are really soft.

 

Make sure and use contact cleaner on the coil connection. Just fixed a nagging misfire on cylinder 3 with that.

 

Denso tt iridem

 

most known tuners recommend .027 and not to use iridium plugs as they are prone to intermittent breakups. .022 is way too tight. 026 is close enough to .027 but .027 is the time honored gap. the best no brainer plug is the gt2 fr6ldc which is "pre-gapped" and if you check it'll be .027.. or you can spend the extra bread on the Bosch FR-6-DPP-332 S but neither you or the car will notice the difference.

"even" cobb advises against using iridium plugs. cobb recommends NGK PFR7B, but why? over the bosch/beru fr6ldc? who knows.

 

Do not run a iridium. Todd at protomotive has me running a denso pk20pr-p8 gapped at .024 at 30+ psi on e85 and never had a misfire.

Before I was running the iridium cheaper plug and caused all kinds of misfires.

 

Ah, I'm reading the Iridiums last longer but have worse conductivity. Mistake on my part. I will order those Densos, Todd is my tuner as well.

 

Yup you will like them a lot. For me on e85 they should last 15k miles maybe more.

 

Been running these for years at .27 and they work great...1.3 bar/93 octane

 

Gap really depends on the boost level you run. Higher boost the tighter you want to run. If your running 20 psi or less a 27-28 is find. 20-30psi you'll want to be 25-26, 30+psi a 23-24.