platinum vs iridium plugs

[97warwagon]

I went into the parts store to pickup plugs and wires for the 97 gtp, the parts Guy gave me irridium plugs and said that they are the oe plugs for the car
i thought it came with double platinums
what do you guys think?
thanks!

[BNaylor]

Are you stock or modded? The parts guy is incorrect. The original equipment plugs were either AC Delco or NGK double platinums. The Iridiums which came out well after 1997 are now the recommended replacement since the OE double platinums are hard to come by or discontinued.

What brand Iridium plug? AC Delco? Make sure they are the 41-101.

[97warwagon]

I checked and they are #41-101
I will be starting on this project within the hour
Am i good to go on this?
Thanks for the help

[BNaylor]

Sounds good to me although I prefer the NGK TR55IX Iridium over the AC Delco if this is a stock engine with no supercharger pulley mods. BTW - NGK makes the AC Delco 41-101 Iridium for GM/AC Delco so flip a coin. Either way you should be good to go.

[97warwagon]

Thank you for your advise
so now it is time to dance with the GTP
I will let you know about the outcome!

[richtazz]

Hey Bob, here's some interesting information for you that I thought you'd appreciate. Since Delphi quit making the plugs for Delco, the 41-101 actually have NGK stamped in the metal base and NGK part #ITR4A15 on the porcelain (as well as the GM long number 12568387). The actual Delco part number is not on the plug itself, only the box . The ITR4A15 crosses to the number you gave also, and both are Iridiums, so I'm not sure why NGK has 2 part numbers, .

This might be helpful down the line if forum members think they may have the wrong plugs installed when they don't see the 41-101 on the plug.

[BNaylor]

Thanks for the heads up Rich. Good info. On NGK Iridiums I found out there are two TR55IX types. One is the Laser version which meets GM OEM specs closely including up to 100K miles. It has the part on the electrode (spoon) for long wear and you are not supposed to adjust it. Then there is the regular NGK TR55IX Iridium which has the adjustable electrode but are actually cheaper than the Laser version. I recently installed the regular TR55IX Iridiums in my Regal GS and son's Alero GL2. They work fine. Got a really good deal for 6 of them. Actually cheaper than the AC Delco Iridium packaged version.

Also, from what I understand the next range colder AC Delco Iridium is PN: 41-985 but NGK has an easier numbering system and availability therefore the choice for modders that desire to use Iridium instead of the Autolite Copper Core.

[richtazz]

I agree with the numbering system issue. It's nice to have numbers that are easily decoded, not the smoke and mirrors show GM uses to stop people from dooing just that. GM thinks their engineers are smarter than us, I beg to differ!!!