Help with AC Delco plug part # please.
Thread Starter
Instructor
Joined: Jun 2000
Posts: 176
Likes: 0
From: Florence KY
Help with AC Delco plug part # please.
A couple years ago I put NGK TR55's in my '98. I feel its about time to change them out and I was going to go back to a stock platinum plug. Guy at the local autoparts store told me they have updated the plug to one with a cooler range and gave me AC Delco part # 41-952. Compared to the stock plugs they are a little longer overall and I don't know if they are the right plugs.
Burning Brakes
Joined: Aug 2000
Posts: 1,132
Likes: 1
From: Morganton, NC, USA
Re: Help with AC Delco plug part # please. (Toyride)
I just changed out my original AC 41-952 plugs after 15K fairly easy miles, most of them at 1500 engine RPM.s. The platinum pucks were missing on all 8, opening up the gap to .065". I guess the theory is that platinum, being a very noble metal ,will not oxidize or erode giving you an advertised 100,000 miles between tune-ups. This would be true if the platinum puck didin't fall off. So now, you are pretty much back to a standard technology spark plug that will probably work good for 15 k miles after the puck disappears that you paid 4 times as much for. Maybe the Bosch or Autolites will last longer? I went with NGK TR-55's. By the way, where do the pucks go? Anyone ever found them embeded in the aluminum pistons or heads? In the cats?
Team Owner
Joined: Oct 2001
Posts: 46,764
Likes: 5
From: Boynton Beach Florida
St. Jude Donor '07-'12, '20
Re: Help with AC Delco plug part # please. (silversport)
RapidFire #12 as well @ 60 Gap... :chevy :seeya
Anyone actually run this in a C5, yet???
Anyone actually run this in a C5, yet???
Bob
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Instructor
Joined: Apr 2002
Posts: 172
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Re: Help with AC Delco plug part # please. (2kbluestreak)
Just installed NGK TR55's today. Three of eight pucks were missing with
only 26000mi. This does'nt bode well for hi-mileage plugs. Especially for
the money. AC Delco might want to do a little more testing.
only 26000mi. This does'nt bode well for hi-mileage plugs. Especially for
the money. AC Delco might want to do a little more testing.
Pro Mechanic
Joined: Oct 1999
Posts: 3,918
Likes: 1,461
From: South-Central Coast California
Re: Help with AC Delco plug part # please. (Toyride)
There are actually two NGKs that are good for the Gen 3 V8s in C5s.
The TR55 is the NGK I'd recommend for stock cars that are driven "normally".
If you run your car hard on the street, you need the TR6 which is a little colder.
If you want a single platinum tipped NGK, use the TR55VX, but know that it's not a wise choice for hard driving and certainly not for racing.
A real problem with the NGK 14mm, .708-in reach, projected tip, resistor plug product line and C5s that are run hard is the lack of a plug that fits those engines in the NGK "7" heat range.
Right now you're stuck with the TR6, which is ok for agreessive street or light racing but really is a bit hot for hard core motorsports use. You also can go to NGK racing plugs but they start at the NGK "8" which is too cold for street or street/track and is a nonresistor plug with may cause RFI.
Denso maybe a better choice for C5ers. It has a number of cold heat range, 14mm/.708 reach/projected tip/resistor plugs in its "Iridium Power" line. Aggressive drivers and racers can try the IT20 or perhaps even the IT22. They come gapped at .044 and I'd open them up to .060.
The TR55 is the NGK I'd recommend for stock cars that are driven "normally".
If you run your car hard on the street, you need the TR6 which is a little colder.
If you want a single platinum tipped NGK, use the TR55VX, but know that it's not a wise choice for hard driving and certainly not for racing.
A real problem with the NGK 14mm, .708-in reach, projected tip, resistor plug product line and C5s that are run hard is the lack of a plug that fits those engines in the NGK "7" heat range.
Right now you're stuck with the TR6, which is ok for agreessive street or light racing but really is a bit hot for hard core motorsports use. You also can go to NGK racing plugs but they start at the NGK "8" which is too cold for street or street/track and is a nonresistor plug with may cause RFI.
Denso maybe a better choice for C5ers. It has a number of cold heat range, 14mm/.708 reach/projected tip/resistor plugs in its "Iridium Power" line. Aggressive drivers and racers can try the IT20 or perhaps even the IT22. They come gapped at .044 and I'd open them up to .060.
Melting Slicks
Joined: Jun 2001
Posts: 2,565
Likes: 2
From: Chicagoland Illinois
Re: Help with AC Delco plug part # please. (Hib Halverson)
Hib:
Do you have any stats or info on the RapidFires??? I bought a package of them but have not replaced my "Denso Type" plugs yet. Any info on these in this application would be helpful. :chevy :seeya
Do you have any stats or info on the RapidFires??? I bought a package of them but have not replaced my "Denso Type" plugs yet. Any info on these in this application would be helpful. :chevy :seeya
