NGK TR55 or AC Delco Iridium
 

been researching here. looks like those are the 2 most popular N/A plugs on here...

wanted to start a little poll on what you have on your car, and if you had both, which you prefered.

I'll most likely just go with the TR55s, but I'm curious what others chose

Also, what gap are you running? .40? .50? .55?

:thumbs:

eta: so much for the poll. it didn't work :rolleyes: lol

I also wanted to ask about the E3s and the NGK TR71IX

i have run both the ngk and AC....AC Delco iridium is where its at

what's the benefit of the iridium?

I run TR55's in mine. I also have alot done to my car. If you car is stock, or mostly stock stick with the AC Delco.

:flag::iagree:

I've got some mods done with an ECS tune and I'm running the NGK's. My car runs great with absolutely no issues and starts instantly all the time. They've been in a while now so this post is a reminder that maybe I should pull them and take a look. However, I also believe in don't fix what ain't broken. I'd probably try Bosch +4's next time. I've used those before and was happy with them.

NGK TR55s with the factory gap

They've worked well for me.

isn't the tr55 like 2 bucks vs ac delco at like 7.

Is the difference really worth the extra money? After all it's the same concept

Had AC Delcos no problems, next set was TR55, worked great, even with my heads/cam/etc mods, then went to TR6 copper, (@35 thou) runs the best ever! I was told a few times to go that route after my mods, finally did....

I'm running the TR-55's in both Vettes. No issues.

Have not run the NGKs, but did have the AC Delcos in my '00. Worked just fine.

Both iridium and platinum are much harder metals than the tungsten alloy found in conventional plugs. Result? They last much much longer and the rate of gap size change (enlarging over time and requiring ever increasing energy for spark) due to erosion is greatly slowed down. Iridium and platinum metals are more expensive to produce.

Like anything else, the trade-off for longer life is higher initial cost. Also, since the plug tends to stay in the cylinder head for a much longer time before service, the need for anti-seize to be used on the threads is greater, to prevent galling/thread pulling upon removal.

Durability/plug life:

Iridium = best
Platinum = next best
Conventional = OK

YMMV ;)

awesome. thanks for that... I'm the kind of guy that likes to swap out plugs once a year ,so I think the NGKs will work perfect for me :)

Thanks!

Tr55

AC Delco for me, You get what you pay for, Changing the plugs once a year is way over kill, These motors will go years without changing plugs unless you have issues..

Just installed new AC Delco iridium 2 weeks ago. Won't have to do it again for a long time. Car runs perfect.

great timing. thanks for the info guys :thumbs:

here's where I'm at. car is a 2000 so I am going to change the plugs and wires. my plan is to install headers at the same time. I don't forsee a lot more mods over the next few years :( should I stick with the iridiums or go with the ngks? I am more than willing to spend more for the iridiums in order to have them longer. just want to know if the few mods I am going to do mean I should go with the ngk. help!!:thumbs:

I use the TR55's at the recommendation of my tuner - (h/c car)
They have performed perfectly for over 2 yrs now.

how long does TR55s usually last?

and the iridiums, how long more?

NGK makes a TR55 Iridium. TR55ix.

And I pulled the Iridium stock plugs out of my 2004 acura the other day. it has 40k miles. They were supposed to last 100K miles. I wasn't impressed with the way they looked. Got about +2mpg after the change.