So at 45k I replaced my plugs, went with the Autolute HT1's. I made the sad assumption that they would be better than the Motorcraft SP-462's. Boy was I wrong, they are actually the same crap (both made by Federal Mogul), anyone running a decent "tune," you may have the same issue with these plugs. Engine developed a misfire at idle, and at cruisin speeds in 2nd-4th gear, this was at 54k. I pulled the plugs last night and was not happy. The "finewire" at the end of the electrode was burnt off on 6 of 8 plugs, and one plug, too say the least was destroyed. I am surprised my engine was not damaged and did not fail. Did a compression check, leak down check and all was gravy. I am dumpin in some Champion 7989's, they are a one peice design and hope this does not happen again. Check the pic, left one is the done in Autolite HT1, the middle is the Motorcraft SP462 (notice the same flawed design) and the right is the Champion 7989. CHECK IT!!!

 

That's really bad!

Can you please enlighten me? What is the "flaw" in the design of the stocker and Autolite plug opposed to the Champion plug?

 

For one, the OE is a two piece plug, the bottom portion of the plug is pressure locked onto the threaded portion of the plug. Two, the lower barrel that surrounds the porcelain on the Champion is a much thicker gauge than that of the OE barrel, so in theory it should hold up to hotter temps and from the looks of it that's where the Autolites ate it...

 

The Motorcraft/Autolite's are a two piece design. However that is not part of the problem here. There some problems with the two piece plug breaking off in the head of 05-07 and early(?) 08 heads(perhaps 09, I can't remember specifically). The heads were changed to accomodate a one piece plug and are different.

 

I switched to FRPP 3V0's when the supercharger went on and they've been flawless. One heat range colder and they're made out of far-superior copper. Platinum lasts much longer, but is inferior to copper at conducting spark.

 

I dunno, but to me that looks like maybe it ran lean?

the biggest trouble with the oe plugs is the breaking off issue. on the champions, please LOOK CLOSELY AT THEM before installing...one of my 8 wasnt threaded all the way- dunno if it woulda damaged the threads in the head if installed or not, but didnt want to find out either.
5 of the 8 had the platinum tips so off center youd need to either gap them diagonally, or bend the electrode off center to align the little platinum tips...mine were so crappy quality wise I didnt change them, will deal with the broken plugs whenever NGK or someone makes a decent plug. I hear the ones from brisk racing are quality, but not platinum, so will need changed more often...

IMO those champions are the poorest quality I have ever seen- really never saw any plug anywhere near that shoddy. I put pics in here somewhere- I'll see if I can find a link.
if you havent bought them yet, Id suggest checking our brisk racing's offering. btw- champion is federal mogul too- made in mexico...109 a set I paid for mine- wrote federsal mogul/sent pics- guess they dont care either.

 

Thanks

 

That's a tuning issue not a spark plug issue

 

Very much so.. Who's tuning this car again?

 

i have the autolite ht1's and my tuning is from tillman and they have been perferct. first time i heard a issue with these plugs, so i hate to sound like there is an echo in the room but i agree that there might be a tuning issue at hand.

 

I had autolite HT1s and HT0s in my 06 from NA at 303rwhp to blown at 501rwhp, all tuned by Brenspeed and never had any problems with the plugs.

 

That was before he traded it in to a little old Nun for a Bimmer

I also have run the HT1 and HT0 with no problem (420rwhp Saleen Blown) but I got a set of FRPP 3VO for christmas that I'm going to install before my spring Dyno test at Brenspeed. Also I pull and check my plugs every 5,000 miles, just to clean and look at them...no problems at all.