Spark plug Autolite or OEM Subaru

i run autolite 63 (gap to 24 thousandths) on my stage 4 for 500 miles with nitrous, they look perfect. 99 cents each. to each his own.

It has been satisfactorily argued that the inexpensive Autolites work as well as the expensive Iridiums, with the understanding that the Autolites must be changed more often.

i just changed mine out.. i put in the autolite 3923's ($4 for the set) . they seem to work fine. one thing to watch out for though - they were all gapped differently out of the package. be sure to measure the gap before putting them in, just in case. (the gap should be .028)

Seems like you did everything except swap out a $2 spark plug. I had a misfire on cylinder #1 first then cylinders #3 and #4 until I went out and bought 4 new Autolite 3923 spark plugs and put them in and BINGO no more problems the car is running strong and not throwing any codes.

I have autolites, they work well, but the car became jerky at part throttle when gapped at .024, runs better when opened wider for some reason.

a spark plug job on an STI can be a 6+ hour job :thumbdown:

I've gotten autolites a few times for some domestic cars and they've been 0.005\" - 0.010\" off seemingly across the board, compared to what the box said they should be. And I wasted a day hunting down a misfire that turned out to be a bad spark plug out of the box.

Don't go with Autolite XP iridium. I had on my Jetta and one of the tips basically melted after 25k. They suck.

I took a peak at mine the other week and the gap was HUGE so gapped them down to .035 and now cold starts are ROUGH. The pugs in there suck, anyway - old autlites.

After changing the plugs from OEM's to Autolite 3923's, the coil packs started popping up. I've read that the Autolites are smaller than the OEM's, so they don't hold on as tight...and then somebody else said this is bogus and they're both the same. Whatever the reason, the coil packs on my car do not like the Autolites.