Which spark plug number is correct - 1999 Z-28

**TeeRod** · 03-29-2011, 11:30 AM

Hello All

I pulled what I believe to be (2nd owner) the original plugs from my 99 Z-28. The part number is AC Delco - 41-952, GM #25321615.

I went to Advance AP the guy gave me Delco 41-110, checked it 2 times and said it was correct.

I absolutely want the same plugs it came with. What is correct?

Thanks very much for taking the time to respond

TeeRod
Orlando, FL
99 Z-28 with a few bolt on's

**My00Z28** · 03-29-2011, 12:55 PM

Originally Posted by TeeRod

Hello All

I pulled what I believe to be (2nd owner) the original plugs from my 99 Z-28. The part number is AC Delco - 41-952, GM #25321615.

I went to Advance AP the guy gave me Delco 41-110, checked it 2 times and said it was correct.

I absolutely want the same plugs it came with. What is correct?

Thanks very much for taking the time to respond

TeeRod
Orlando, FL
99 Z-28 with a few bolt on's

the plugs they gave you are going to be direct replacements for your car. things change every year with plugs and they will make new p/n i work at Advance auto and those are the only AC-delcos that they offer for the car... if you go to ac-delcos website and search your car it will even say the part number for your plugs is 41-110!!!

**konigandy6** · 03-29-2011, 02:46 PM

The new GM part number for Delco iridium tip spark plugs for the LS1:

GM# 12621258

**SSwt00SS** · 03-29-2011, 03:37 PM

why do you want the same plug?

if you are changing them, its a great time to get the NGK-TR55 plugs. ideal plugs to use for our cars.

LS1 Stock
Thread – 14mm
Reach - .708”
Socket – 5/8 hex
Seat - Taper
Stock Heat Range: 5
Gap: .060
Plug: NGK TR55 (stock number 3951); NGK TR55IX (stock number 7164)

**My00Z28** · 03-29-2011, 09:57 PM

They need to cross the tr55 they r not the same u want a 3951 tr55

**bryceslu** · 04-01-2011, 07:47 AM

Originally Posted by SSwt00SS

why do you want the same plug?

if you are changing them, its a great time to get the NGK-TR55 plugs. ideal plugs to use for our cars.

LS1 Stock
Thread – 14mm
Reach - .708”
Socket – 5/8 hex
Seat - Taper
Stock Heat Range: 5
Gap: .060
Plug: NGK TR55 (stock number 3951); NGK TR55IX (stock number 7164)

um not sure about that. nothin wrong with the Delco Iridiums.

I wouldnt put ngk 55s in my car either.

**SSwt00SS** · 04-01-2011, 07:23 PM

Originally Posted by bryceslu

um not sure about that. nothin wrong with the Delco Iridiums.

I wouldnt put ngk 55s in my car either.

never said there was anything wrong. for my setup, the NGK's have performed well. i simply made a suggestion.

**konigandy6** · 04-02-2011, 07:15 AM

Originally Posted by SSwt00SS

never said there was anything wrong. for my setup, the NGK's have performed well. i simply made a suggestion.

+1

I also run 55's and they're excellent. The new Iridium Delco's are not bad either. But back in 02, they were platinum.

**My00Z28** · 04-02-2011, 07:56 AM

Originally Posted by SSwt00SS

never said there was anything wrong. for my setup, the NGK's have performed well. i simply made a suggestion.

Originally Posted by konigandy6

+1

I also run 55's and they're excellent. The new Iridium Delco's are not bad either. But back in 02, they were platinum.

im running 55's in mine also $15 a set of 8(NGK) or $50 for a set of 8(Delco), so far the NGK's seem to be great, about 500 miles so far and ill probably replace them every year for the price not a big deal!!!

**konigandy6** · 04-02-2011, 12:42 PM

Originally Posted by My00Z28

im running 55's in mine also $15 a set of 8(NGK) or $50 for a set of 8(Delco), so far the NGK's seem to be great, about 500 miles so far and ill probably replace them every year for the price not a big deal!!!

The price is right, but replacing them every year would be a huge PITA!!

**CHAUCEY** · 04-02-2011, 01:44 PM

Delco 41-110 should be correct.

**My00Z28** · 04-02-2011, 02:56 PM

Originally Posted by konigandy6

The price is right, but replacing them every year would be a huge PITA!!

well most only put like 5,000 miles on their cars i have tripled/quadrupled that number with my first car, i put 30,000 miles on it in a year and a half!!
you can change the plugs in like 30 minutes... i spend longer washing and drying my car than i would replacing the plugs lol!

**98maro** · 04-02-2011, 03:18 PM

Only plugs I would use on ls1 is acdelco iridiums.
I put them on my Z. On my ss I have acdelco rapid-fire I dnt feel no difference. But next time I'll get the iridiums.
I would never buy NGKs.

**konigandy6** · 04-02-2011, 03:23 PM

Originally Posted by My00Z28

well most only put like 5,000 miles on their cars i have tripled/quadrupled that number with my first car, i put 30,000 miles on it in a year and a half!!
you can change the plugs in like 30 minutes... i spend longer washing and drying my car than i would replacing the plugs lol!

30 minutes?!?!?!

Hey, since you're from MI... you're gonna have to go ahead and change mine out for me!