Regarding Champion 7989 plugs, just make sure you check them over as this happened to me:


Bought mine from RockAuto about a year ago, one plug the little cone slipped over the spark area (brand new in box). Rock Auto wouldn't warranty their sale and had to go to Champion Canada who arranged to replace locally. The past few weeks my 06 Mustang GT has been driving me crazy, running rough and misfiring. Finally, finally after trying everything with Maf, throttle body, different tunes and almost checking phasers, timing and worrying about broken comp cams valve spring, I decided to put the original motorcraft spark plugs in and voila, car is as smooth as silk again. Examined the Champions 7989 and found on one that the metal neck just above the threads and the socket head was cracked and broken on both sides. Absolutely no reason for this to be broken as car had ran well for over a year and the plugs had not been touched. My experience with Champions. Have photos of both.

 

Ive never liked champion plugs since back in the 80's with a 2 cycle quad...NGK is a great plug.

I bought a set of the champions for my car too- but wont install them, poorest quality parts ive ever seen. one of the 8 wasnt threaded as far as the other 7, might damage the head if installed, plus crooked platinum tips on top of crooked welded electrodes- I wouldnt trust bending them that far, plus the platinum tips so far off you'd have to gap them diagonally... sure long as they spark they'll 'run fine', but my 'likely to break off' motorcraft junk design, but better made run fine too...wish I woulda bought the Brisk and just chanced every couple years...I hear Brisk makes a good quality- but non platinum- one piece plug.
Maybe this winter when I do the clutch I'll try removing the stockers and put in Brisk's... just wish NGK had a platinum plug for our cars, they are top notch quality-wise IMO. Accell was IMO the best US made plug, but they had limited applications, and didnt come in platinum(at least long ago).

I never 'liked' champions after a few bad experiences with my old quadracer fouling plugs after just a hour or so, where a NGK would run for a whole season and still be fine...after seeing these mexico made mustang plugs I'll never give them another chance to sell me anything.

 

I've been running the Champions for over 50,000 miles and no problems so far. I inspected the plugs before installing them and they looked adequate. They seem to have poor quality control but if you get a good set it seems they are OK. I might remove and inspect in the future.

 

thats good to hear...maybe the set I got was done on 3rd shift the friday before a holiday weekend or something

if I had a set that ran that long that I knew wouldnt snap off, I'd leave them alone till the 100k

 

I also have over 50K on a set of Champions with zero problems. I just bought another set to install sometime in the future, maybe at about 75K miles. I took each of the new set out of the box and closley inspected each one - they all looked good. I am not doubting any of the stories of bad plugs, but so far I haven't had any problems. I sleep better knowing the Champs won't snap in two when I remove them. When I changed my original Motorcrap plugs, 6 of 8 broke. I'll take my chances with the Champions.

 

Just make sure you check them closely. Here's what I posted on another site.

Bought mine from RockAuto about a year ago, one plug the little cone slipped over the spark area (brand new in box). Rock Auto wouldn't warranty their sale and had to go to Champion Canada who arranged to replace locally. The past few weeks my 06 Mustang GT has been driving me crazy, running rough and misfiring. Finally, finally after trying everything with Maf, throttle body, different tunes and almost checking phasers, timing and worrying about broken comp cams valve spring, I decided to put the original motorcraft spark plugs in and voila, car is as smooth as silk again. Examined the Champions 7989 and found on one that the metal neck just above the threads and the socket head was cracked and broken on both sides. Absolutely no reason for this to be broken as car had ran well for over a year and the plugs had not been touched. My experience with Champions. Have photos of both.

 

I finally got some time today to change my plugs @ 50,000 miles. Got them all out without breaking any - I had been worried about this after reading about the problems with the 2 piece OEM plugs. Several of them were real stubborn, but I just turned them a little at a time to let the carb cleaner soak in and they eventually loosened up. I put the one-piece Champions in so I will see how they do.