Which Spark Plug?
 

2001 Monte Carlo SS

Thinking about doing a tune up and changing the spark plugs. I notice there are Bosch installed at the moment. The manual calls for AC/Delco 41-921's which appear to be discontinued? Autozone sells AC/Delco 41-101's (Iridium) and 41-901's (Double Plat).

What is the difference in these and what is the recommendation? Which is closest to what came in the car? I'm assuming the 41-901's?

Thanks guys. :thumbsup:

NO BOSCH! Some times you get lucky, but my experiences with BOSCH plugs, BAD (multiple times used in GM v6 engines and either immediate or premature failure).

I would get AC Delco or NGK (fun fact: some AC Delco plugs are rebranded NGKs).

I've been using NGK platinums in my 3100/3400 engines. Yet to change them in the Monte (my only 3800), but I'd have zero issues with NGKs.

I know Plats and Iridiums last longer then copper. I honestly don't know the difference between plats and iridiums (i'm guessing temperature or better spark in one vs the other).

To my knowledge all 2000+ 3800's had iridiums. I'd go that route. Also, check rockauto.com, lots of times you can get the plugs a LOT cheaper then the local stores (I can get 6 NGK plats shipped for under $3 a plug typically).

Don't forget to get new wires while your at it.

Awesome thanks for the info. I'll give rockauto.com a look. I read somewhere some of the AC/Delco's were made by NGK I didn't know that.

ngk plats if your not going to modify or very little. no on the iridiums imo, thats just personal pref.

if you plan on modding, go with the standard cheap autolite copper.

I use iridium AC Delco plugs. 41-101 I think is the number

I don't plan on doing any "mods" but there is a CAI filter already installed when I bought this does that change anything then as far as what plug I should consider?

I actually have some factory AC Delco plugs that have "AC Delco" printed on the ceramic part, but has NGK stamped into the metal part. First time I saw that was the first time I decided to put NGK's into a GM v6 (gave me a good feeling that I'm not really risking much if GM is re-branding NGK plugs). :)

you should be fine with either the plats or the iridiums, i just prefer the plats myself.

I have a question, new to the forum. Just bought our first Monte Carlo and it needs a tune up. It is a 2004 3.8 supercharged and I was wondering which of the plugs you have been talking about would be good, but also provide the performance some fuel mileage is good but I want the get up and go too. Thanks for the help.

autolite platinum 606 or 605's if you have any mods done. if you plan on doing any modifications over the course of the next year, just get the standard copper autolite 606 or 605.