Iridium plugs

[Ames63]

I am considering replacing my spark plugs with the new Iridium plugs on the market, has any one had any experience with them and would you recommend buying the accompanying wires to go with them? <img src="http://forums.aaca.org/images/graemlins/cool.gif" alt="" />

[jchudyk]

Iridium plugs came standard on my 2002 Buick with 3.8 engine. They are supposed to last 100k miles. After 75k miles with no spark plug problems, I decided to put them in my '89 Reatta. The Reatta is a minimum use Summer car, but so far I have had no trouble with sparkplugs. I hope that the Iridiums last the life of the car, because the rear three sparkplugs are no fun to change.

[Roadster90]

Oh boy o boy o boy!! More neat stuff to drain my already insignificant money reserves <img src="http://forums.aaca.org/images/graemlins/crazy.gif" alt="" />.....how much and where are they obtained please?

<img src="http://forums.aaca.org/images/graemlins/smile.gif" alt="" />

thank you

[jchudyk]

I bought mine at PEP BOYS, paid about $8.00 each.

[Guest waxbgone]

I got tired of replacing ignition wires that I invariably broke when I changed plugs. I sprung for the iridium plugs and new wires and put on 125,000 miles with no visible change on the plugs. Now, the second thing I do to a new reatta (after fixing the headlights) is put in the iridium plugs. BE SURE TO COAT THEM WITH ANTI-SEIZE COMPOUND. If you don't, the threads will come out of the head when you remove them many miles later.

[Guest Mike_s]

As I understand it, Iridium plugs have a resistance close to that of standard plugs, platinum plugs I believe have a higher resistance.

[jchudyk]

I think that the major difference between platinum and iridium sparkplugs is iridium's resistance to gap erosion. Platinum is good in that respect, but iridium is better.

[Guest Mike_s]

I think your right on the wear/erosion aspect, but I was referring to the electrical resistance, I think that since a Iridium plug has a lower electrical resistance than platinum it probably gives a hotter spark and "maybe" a bit better gas mileage and power

[Guest Mike_s]

FYI Here's some Denso PR

http://www.densoiridium.com/voltagerequirements.php

Densos run about $11.00 around here

[Ames63]

I'd like to thank everyone for their input, i feel confident that iridium plugs and wires are the way to go. i plan to change them out this weekend.

Thanks

[Roadster90]

Very neat thread. Will these plugs pair up with standard Delco wires please?

[jchudyk]

All external dimensions are the same as a regular sparkplug. The iridiums I used were AC Delco. I don't remember the stock #, but they are the same ones listed in the book for my 2002 LeSabre. They come with a .060 gap, close the gap to .035 or so if you have the stock Magnavox (square) coils on your Reatta.

[Guest inthespot]

Would this be true on AC Delco plugs also? I just got new plugs from the Buick dealer and they said they should be gaped at .060. I do have the square Magnavox coils. Is the .035 gap just for the Iridium plugs??

[jchudyk]

The iridium plugs were marketed long after the Magnovox coils went out of production on new GM 3.8's. The Magnovox coils are not as hot (amperes) as the newer Delco coilpack. That is the reason for the smaller gap. You could try them at .060, but you might get a full-throttle miss (that's when spark demand is greatest)