I was looking at sparkplugs recently and wondered waht would be a great performance long term sparkplug?  I looked at AC Delco, NGK, & some autolites.  AC-D does not have a great vast selection (that I know of) of heat ranged plugs (for those of us with a few mods) and cost upto 6.00 a plug.  Autolites are in my opinion, are known to burn up rather quick causing you to replace plugs more frequently (3.00 and up).  NGK is by far (IMHO) the superior plug that can perform the best while lasting a long time, but the ones I was looking at are 8.00 a plug (ouch) . 

Is there something I am missing or tricks that I dont know that can yield the same results at teh same cost without sacrificing something in the end?

I just want 6 plugs, two ranges colder than AC delco stock plugs without costing me my two arms and half a leg. 

:icon_confused:  :icon_frown:

I used the NKG Iridiums in my car, shortly before switching to Champion Iridiums...both Iridiums made the car idle really funky and I felt it robbed power. When I switched back to AC Delco, I had a smoother idle, and noticeably more power.

So I take it you're lightly modded or stock and used stock type plugs? 

Would you happen to know of a plug one or two ranges colder than stock plug supplied through AC Delco?

The AC Delco plugs our cars call for are cold enough.

ya, I have always heard that the AC delcos are the best plug to use in the 3.1....

I just figured that if you start adding some great deal of mods that plugs would eventually come into consideration. 
Has anyone scanned for kr?  I know most tc'ed setups dont really have an issue with kr, but you never know what you'll find until a scan test is done.

The stock plugs seem to do pretty well with the stock turbo getting as much as you can out of it. No KC's. I have had AR472 plugs in for 3 or more years, (same plugs) work well street and strip. The stock plugs ran out with the first turbo upgrade. Don't remember what heat range the AR's are but they definatly work. :icon_biggrin:

Jud

In response to your question, TGed, my car is not stock, and fairly modded with decked heads, rebuilt engine, T-28 Hybrid Turbo, Chip...bunch more. AC Delco, like mfewtrail said, work fine for the 3.1 TC.

Quote from: grinders_18 on September 14, 2007, 05:06:29 AM
In response to your question, TGed, my car is not stock, and fairly modded with decked heads, rebuilt engine, T-28 Hybrid Turbo, Chip...bunch more. AC Delco, like mfewtrail said, work fine for the 3.1 TC.

Yep the AC Delco Rapidfires R42LTS work very well in our cars, stock or modified.

Awesome, my pocket books thanks you all for your input. 

Alright back to the drawing board...  It would be 4+ weeks before I could get the R42LTS's so autolites might be my next choice...  Are the autolite 103 the next comparable plug?  I know the SC guys use them when they cannot afford the 10.00 AC delcos, but they have to be replaced every oil change almost if not sooner.  If you were in my shoes and kind of needed to drive the car due to certain technicalities, would you use the 103's for the short time then swap to the factory required plugs?  Anybody have any bad experiences with these?

All I know about Autolite is in my first TGP, I replaced whatever was in there with the Autolites, not sure which type. The TGP ran pretty bad with them. However, in my 93 Camaro V6, the Autolites ran just fine...so I just stick with Delco lol.

Well the parts stores crossreferenced the stock plug and came back with the, "autolite 103" .  So did yours have the autolite 103?
They do list MANY others that may mislead you. 
    Autolite xtreme XP103
    Autolite double plat APP103
       Autolite platinum AP103
    Autolite resistor 103


As you can see, I am only inquiring about the last one [Autolite resistor 103] and I might give those a try since I do 'need' the car now. 

Quote from: TGed on October 23, 2007, 12:42:43 PM
Alright back to the drawing board...  It would be 4+ weeks before I could get the R42LTS's

WOW   4 weeks.   :icon_eek:   Where are you located. I think I got a set at the shop, let me know if you need them. Autolites do not work very well in GM products. I think it's got something to do with Ford. Motorcraft plugs are made by autolite, anybody see where I'm going with this.   :icon_rolleyes:    Have you looked for a set of champions, I would use them before autolite..   Good luck

I'm currently running Autolite 103's in my TGP, they work just fine and have been in the car for a few months and a couple hundred miles. As far as changing plugs at every oil change, who told you that bs? I'm assuming your read that on ClubGP. If so, ignore that crap, something is wrong with their tuning or something else if they're eating up plugs that quickly. The standard copper core plugs are fine for 30K mile intervals. I know people that run them a lot longer than that though. By the way, do you have any Advance Auto chains nearby, they stock the original AC Delco plugs. Autozone doesn't seem to carry them anymore without having to order them.

PS: I know a few local Grand National owners that run 103's and are clicking off low-mid 10 second passes at the dragstrip.