NGK make Iridium plugs to if you MUST have them (and they are only $6 each - much cheaper than Denso). I had them on my car and they didn't feel any diffrent, really. I am now using the cold Motorcraft plugs that Demon suggested. I forget the number, but I had to order them special.
When I install the turbo I will be using NGK TR6's though.
If you want I still have the iridiums and can send to you for $10, if you wann try them. They are still perfectly fine.
