Do you change the gap on iridium plugs?

[5:04]

I just bought a set of Denso IW22's for my Carbed and 9.5:1 911S since I heard they're very resistant to fouling and my car runs pretty rich. They come gapped at .028", however I normally set my gap to .040". Do those of you who are running Iridium plugs open the gap, or are you not supposed to?

[Jared at Pelican Parts]

Typically, you don't gap iridium plugs. Curious why you decided to use these rather then regular Bosch Supers (which you can gap).

[5:04]

I have Magnecor wires on the way and since the car is running rich I wanted to change plugs for good measure. I searched here and read great things about the Iridiums and that they are not prone to fouling on MFI and Carbed cars. I also get them at cost so they weren't too expensive.

Thanks for the advice, I'll put them in that way then.

[tobluforu]

If you try and gap them be very careful because it's very easy to break the tip off. Ask me how I know..

[Rot 911]

.040 is a pretty wide gap for an old 911S with carbs. What ignition system you using?

[5:04]

I guess I shouldn't say I, I actually set the plugs I put in last year at .030" and the P.O. had the ones I took out at .040" and he had the the car set up pretty well. I also did a bit of reading on gaps yesterday and it seems .040" was what many people with upgraded ignition units set it to. The car has the factory Perma blue and some sort of spark enhancement box I'd never seen before. In the near future I'll probably take it out to put in a new MSD unit and coil.

[Jared at Pelican Parts]

.040" is probably going to be too much for the factory box. With an MSD it should work well.

[5:04]

Thanks Jared, I'll leave them at the factory .028" then

[RSTarga]

Why don't you lean the car a bit?