Been thinking about going to the Iridium plugs too. My father has them in his jeep and it made no difference. Just recently read a post on Pirate about the Iridium plugs and BlueCoyote3 was talking about using the double electrode plugs used in the 5vzfe (3.4 Taco motor). They fit the 22r/re with no issues. What makes them 'good' is that the spark kernal is out in the open, not hidden behind the electrode and they are only $1.69 at Autozone.

Part #'s are:
NGK BKR5EKB
Denso K16TR11

I may try this and see how well it works.

Adam W.
87 4Runner SR5 - 22RE w RV head & TRD Cam, LCE header, W56B-HD, 4" Stage II, 1.5" BJS, Rancho T-bars, F 5.29, R 5.29 ARB V6 FF w LC disks, 35" MT/R's

85 4Runner frame, 5" Marlin springs, 5:29 ARB HP front. Work in progress - Always!