Iridium plugs
Race Director
Joined: Jun 2004
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From: WI
There are many gimmick plugs, don't waste the money. There have been a few recent topics on plugs, running a search will have more info.
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From: Cape Cod, Mass.
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I have used Iridium before and they did nothing special other than deplete my funds. I just put a set of AC Delco Rapid fires in my 85 and it runs great. I beleive they are platinum. Not cheap but not as bad as the iridiums.
Burning Brakes
Joined: Dec 2005
Posts: 805
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From: Hickory Flat Ga
You'll get many opinions as usual here. That's what this site is for. Your LT-1 will run fine on most flavors of plugs, but since they are such a pita to change I use NGK TR55 IX. They are irridium and cost much more, but this is my hobby car so I spend the cash on the best.
I had AC DELCO Platinums for 30k miles with no indicated wear when I switched to NGK. I think I have a little smoother idle with NGK. There are hundreds of posts on this in previous threads.
I had AC DELCO Platinums for 30k miles with no indicated wear when I switched to NGK. I think I have a little smoother idle with NGK. There are hundreds of posts on this in previous threads.
Drifting
Joined: Dec 2003
Posts: 1,493
Likes: 94
From: Westfield MA
In the days of carburetors and points, plugs lasted 3K miles, it would have been worth it to me to pay extra for some that lasted longer. Now with electronic fuel injection and ignition, standard plugs last forever. Ok, not forever, but I like to change them every year or two just so they don't fuse themselves to the heads. Standard plugs seem to handle this just fine, so to me, anything more expensive is a waste of money. Your mileage may vary................
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From: Fort Knox, KY
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I would just go with the NGK TR-55 Double Platinum. I've got more than 11,000 miles on mine and they're stilling hittin' like new money.
The price is right too. Around $2 each or less on sale.
I've never used the Iridiums. The price alone is enough to deter me.
The price is right too. Around $2 each or less on sale.
I've never used the Iridiums. The price alone is enough to deter me.
Last edited by onedef92; Aug 14, 2007 at 03:30 PM.
Race Director
Joined: Feb 2003
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From: Lake Wylie SC
Okay, I seem to be in the minority here. I installed NGK TR55IX (Iridium) plugs about 20K ago. They have been flawless. Would any other plug work as well? Probably. I just made a trip of 800 plus miles and my mileage was unbelievable. So, I can assume that my plugs are still working just fine. Just so you know, my LT1 is mostly stock.
Thread Starter
Advanced
Joined: Aug 2007
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From: Gilbert AZ
Thanks for all the input guys. I've seen some places that Iridium plugs aren't too expensive, but if there isn't really any performance enhancements over Platinum, then I think I'll go with what I know is good for now.
Race Director
Joined: Jun 2004
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From: WI
Neighter plat or iridium are a performance gain. They might last longer, allowing less changes of the plug but the cost of a normal plug would still be far exceeded.
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Joined: Sep 2000
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From: The Top of Utah
Originally Posted by Phalanx_vette
Thanks for all the input guys. I've seen some places that Iridium plugs aren't too expensive, but if there isn't really any performance enhancements over Platinum, then I think I'll go with what I know is good for now.
Originally Posted by onedef92
I would just go with the NGK TR-55 Double Platinum. I've got more than 11,000 miles on mine and they're stilling hittin' like new money.
RACE ON!!!
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From: Fort Knox, KY
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No exotic plug is going to make an ounce of difference in performance. The plug goes ZAP and the air/fuel mixture goes BANG. That's all there is to it. Most of the exotics will last longer. If you have an aversion to changing your plugs or are paying someone else to, there may be some economic benefit in the platinums. There is NO performance benefit over the cheapest plug.
So far you have demonstrated the TR-55 Double Platinum plugs are good for at least 1/3 the life of the cheapest plug.
RACE ON!!!
So far you have demonstrated the TR-55 Double Platinum plugs are good for at least 1/3 the life of the cheapest plug.
RACE ON!!!
My previous plugs were Autolite Platinums and I had them in there for more than 50,000 miles with no issues. Try that with a standard, copper-core plug!
At $2 each, I can easily afford platinum plugs. I won't pay $15 a pop for iridium plugs, though.
Le Mans Master
Joined: Oct 2006
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From: Dayton, OH HAWG: "this is Off Topic...it can get a bit north of care bears and strawberry shortcake in here"
St. Jude Donor '08-'09-'10-'11
I got a set of Iridium plugs for my MINI as part of an upgrade. They were included, so I figured WTH. Gone in 15K miles, or thereabouts. On a stock car, you'll see no gains from these plugs. Run boost, like the MINI, and they're likely to wear out. I'm not the only one who's had troubles.
On our race car, though, you can't just se any old plug. The high boost tears the crap out of them quickly. We started running Brisk plugs, and they're amazing. Cost more, but they keep the car going. I'll probably run them on the 383 when it's installed.
http://www.briskusa.com/
On our race car, though, you can't just se any old plug. The high boost tears the crap out of them quickly. We started running Brisk plugs, and they're amazing. Cost more, but they keep the car going. I'll probably run them on the 383 when it's installed.
http://www.briskusa.com/
Melting Slicks
Joined: Oct 2006
Posts: 2,314
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From: In a van down by the river! Florida
I've used NGK Iridiums in my DD for a long time (97 cavi), and when it came tme, I used them in my truck as well (99 silverado z-71).
And when it comes time on the vette, they will go in it as well.
I like them, they have performed very well for me, and are not as expensive as some are making them out to be, YES, Denso's are 15 each, I pay $4 for NGKs that are in my other 2 rides.
And when it comes time on the vette, they will go in it as well.
I like them, they have performed very well for me, and are not as expensive as some are making them out to be, YES, Denso's are 15 each, I pay $4 for NGKs that are in my other 2 rides.
Melting Slicks
Joined: Jun 2004
Posts: 3,253
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From: Castro Valley CA
THE BRISK PLUG!!! That is absolutely new. That plug alone should keep the spark plug controversy going for another 2 years. I myself am using the single electrode Bosch platinum plug, runs perfect.
$60 for a plug change. The Delco FR5LS are under $2.
Le Mans Master
Joined: Oct 2006
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From: Dayton, OH HAWG: "this is Off Topic...it can get a bit north of care bears and strawberry shortcake in here"
St. Jude Donor '08-'09-'10-'11
