Most of the issues I had and saw were in Gen1 sbc's. My brother put some in his wife's grand prix gtp, even though I told him not to, in 10k miles he had a severe miss. When he pulled them they were in bad shape according to him. I have never and will never run them in a gen3 engine to find out if they are good?

 

This is some good info. I've always used Champion or NGK spark plugs but that's just me. My truck currently has whatever came in it from the factory.

 

I too have had problems with Bosch ****. I was 450 miles from home and the platinum came out of the white porcelain and was causing a huge F-in misfire. The "platinum" came out and was pretty much welded to the strap. Not a good sound to hear when so far away from home. Of course I did not find this problem right away, cause I had just changed the plugs 2 days prior from going on my trip. Like one of the guys said in an earlier post, a shop that I had taken my car to in the past would ask when people called about engine problems if they had Bosch plugs. If they said yes then take them sum bitches out. I also worked at a autoparts store and lots of people would bring bosch plugs back. I tried not to sell them to anyone but the customer wants them they get'em. Anyway Ac Delco or NGK will be best for Gen III motors.

 

i had them in my truck for about 2000 miles and they made the truck run worse. they arent set up for a specific heat range like oem pluggs are so they dont burn as well. i think they are crap