449er

I have a 2010 base LS3 auto car. I recently had headers installed & the installer broke one of the original plugs during the process, he replaced the originals ( AC/Delco 12621258 ) with NGK plugs at no cost to me, the replacements are NGK TR55 stock # 3951. Are these the correct replacements? thanks

rkj427

those appear to be for the C5 engines................

link below from Summit with those listed for your application................

https://www.summitracing.com/search/...8%2B4294950196

CMY SIX

$1.59 plug for $10.00 a plug iridium I'd say that's wrong, but it will work

rkj427

he didn't ask if they would work...........
he asked if they were correct...............

your response provided NO relevant information to the OP's original question.............

Dcasole

he never does ......

449er

I talked to my tuner about the NGK plugs he installed & he told me that the TR55 plugs work well in his experience with the lsx cars & had nothing to do with cost, the TR55 plugs are a solid copper core & work well in performance applications, the car does run very well, no complaints here on that

Dcasole

They are a good plug , i did read that NKG caused some alternator issues for some , not sure if it was this plug

Turbo6TA

Very true .... TR55s are a very good plug, an do work well with LSx engines.

Only downside is that they certainly will not last as long as the OEM iridium plugs.

Turbo6TA

One the other hand, your mechanic could have bought just the one OEM iridium plug that he broke a little cheaper that a whole set of NGK TR55s.

Oh well ...

ls1121

Simple answer....NO.....they are not the "correct" Plug.

They will work but need to be changed more frequently.

The Factory Plug is AC Delco 41-110 Iridium Spark Plug. You can check your Owners Manual for information like this.

He actually just created more work for you doing this.

Not So Fast

Plus I just bought a set for my header install and they were like $30 on EBay, pretty reasonable and correct Why mess around
NSF

lwise4

Ah the cheap plug! Just a heads up, I am looking to replace my 2008 plugs. The manual and service manual call for Ac41-985. All I find is AC41-110 which I am told is a correct plug for the 2008 LS3. I ordered a set from EBAY listed as ACDelco supplier. When I place the order it says payment is going to China! I emailed the vendor and told Him that if the plugs were not genuine ACDelco I wanted to cancel the order. He canceled the order.

I guess that if you see a product at half the price of Auto Zone, it probably is not the same especially if the guy you are dealing with has a name like ZXYGEN.

Not So Fast

Well maybe what you say is true, I don't know but I bought these from osrammotrs, EBay, A/C Delco 41-110 and they are in my car, and were brand new in the box, gapped and ready to install.
It says US seller so I dint know about China, they were $35 at the time I ordered. now looks like $37
NSF
http://www.ebay.com/itm/SET-OF-8-AC-...-/272549781419

BlindSpot

NGK makes two grades of iridiums - the Iridium IX and the Laser Iridium. Both are correct apps, but the laser is a higher quality. Here is where the internet can work against you as you're shopping for an iridium and thinking you're getting a deal and it might be the cheaper iridium. LS engines are notorious for munching on the iridium tips. Found two on my 40K NA engine before going boosted. With the tip gone, the gap on two plugs was .080. At first I went...wait...what? Then saw there was no tip.

BlindSpot

The NGK TR55 is a copper/copper plug, the correct temp range for a stock LS engine. The TR5 is a copper but only the tip is copper. Speed guys like using them BC they are adjustable, where iridiums come pre-gapped and should not be regapped. But, the TR55s have a very short life (like in the old, old days).

I tried TR55s for a while when I was NA, but in just a couple thousand miles the gaps had widened significantly. I am using TR6s and a narrow gap now with a blown app. Here is where an iridium doesn't work as they come .040 and I need .025.

CMY SIX

not as good as an IRIDIUM and that was the point of my post, ALL the info one should need, instead of a whinny nanny

buckmeister2

I wrote about this several weeks ago. There are sellers on ebay who are using the ACDelco logo, and claiming authenticity, when in fact, they are selling a product from China.

buy your plugs from a local retailer, or RockAuto.com. I bought from Rock, and they are cheaper, and there is a $3 rebate per plug. My final cost for the plugs was about $16 for the set.

buckmeister2

Following is the ebay item number and seller of the fake AC Delco plugs.

252834826177 gzbacai2016

This seller gets the plugs from CHINA. He advertises them as authentic ACDelco plugs for the C6. They are not. I wrote him about a month ago, and he openly admitted they are not ACDelco. I have tried to report the item, but for some reason, am unable to get the "report an item" screen to work.

DO NOT BUY THESE PLUGS!!!

Dano523

If you need a colder plug, then the 41-104 that comes in the LS motor.

The plug will still last the 100K, as well not cause problems with RF noise through the electrical system to cause the alternator low voltage problems

Point blank, the resistance on the OEM spark plugs and OEM spark plug wires are high for a reason. They help to suppress RF noise in the electrical system from the spark plug coils that can cause all kinds of alternator charging problems.

Not So Fast

I found his ad on eBay and it states "From China" right at the top of the ad, then in other ads it doesn't say it until you look closer at the item description about in the middle of the ad as this one does
http://www.ebay.com/itm/8x-Set-of-AC...EAAOSwlndZGRp6
Sort of shady isn't it.
The seller I bought from doesn't mention China anywhere, it only says US seller, so I hope they were authentic. At least they weren't in the low $20 range which would have made me suspicious right off.
I don't know where A/C Delco actually makes their plugs, tried looking it up but couldn't find out where, wouldn't surprise me if they were made there thou.
Thanks for the info
NSF
PS I just went on his ad to ask where they were made and if they were indeed authentic A/C Delco plugs, I'll report any answers.
EBay is pretty strict and always favors the buyer so it seems strange that they haven't interceded if this is bogus. Wonder if anyone has contacted them ???