Platnum Vs Irridium plugs

[Hailz]

Hi guys, hey i was just having a wee think the other day and wondered if there's any gains to be had by running the NGK Irridium plugs as opposed to the factory recommended Platnum jobbies as from what I can gather the Irridiums are meant to be a slightly better performing plug - but don't quote me on that.

When I first got my GTB I put new plugs put in which were the recommended Platnum ones, the ones that came out were Irridium's, before the plug change the second turbo would'nt come on in 1st gear - coincidence ???

Any thoughts/experiences on the matter would be good

[black_wag]

i got told from the garage to just run the cheapest plugs you can get and change then when you do an oil change as subys dont like the iridiums very much

[WRXONP]

Really ? I ran iridiums in my old ver 2 and it seemed fine ? But in my current sti I just run cheap plugs . . So im looking at going to a colder plug and go to iridium or platinum but dont know what to choose ha ha . Pipe up people

[gotasuby]

i run irridioms one heat range colder as im running 25psi and still going strong with 3ms dwell on gtb coils no missfires yet

[1989RS]

im pretty sure platnum plugs last alot longer and for turbo subarus you are supposed to gap the plugs to 0.8mm so that the plug runs more efficently. did it in my car and it runs alot better on cold starts and while running hot

[Hailz]

 1989RS said:

im pretty sure platnum plugs last alot longer and for turbo subarus you are supposed to gap the plugs to 0.8mm so that the plug runs more efficently. did it in my car and it runs alot better on cold starts and while running hot

Yeah the platnums are meant to last 40,00km's longer than the Irridiums according to NGK's website.

I also got told buy the guy at BNT (bearing in mind he's no trained mechanic) that the Irridiums aren't insulated to the extent they need to be so send a wasted current back - or something to that effect that can dick around with things, but have never heard that from anyone else.

And I thought the plugs you brought now days were pre-gapped and ready to go?? I've put probably 15 sets of plugs in cars for mates ect over the last couple of years and never gapped one

[WRXONP]

You can get pre gaped plugs . Example . BKR7EIX 08 would be a 0.8mm gap . BKR7EIX 11 would be a 1.1mm gap . BUT never trust the gap from the box. boxs get knocked around during freight and you check with feeler blades and theyr out if they have been knockd around. . . worth it to just check them. i red somewhere online (cant find link now) that iridium is a beter conductor then platinum ? maybe just some slick internet info though ?

[johnny5]

I'd say there is also alot of merit indexing spark plugs be damn hard in a sub as you cant see the plug when its in but there are some free gains in power jus from put the electrode in the right position relative to the fuel and air mixture

[Pelvin]

So ..... platinum is best fror our subis? I wana replace my WRXs plugs as well as the Ht leads

[Timmah]

 Pelvin said:

So ..... platinum is best fror our subis? I wana replace my WRXs plugs as well as the Ht leads

Platinum is also what they roll out the factory with

[WRXONP]

Most places just say that platinum and iridium just last longer but dont have a performance gain