Bosch Platinum +4 plugs

I use the Platinum Plus 4's in my 97 Grand Am with a 3100, V6 and, am quiet happy with them. However some owners of cars with the 3400 V6 have said they seemed to have lost performance with them. I have also heard, from some of the owners with the 2.4liter, 4 cylinder engine that they have also experienced performance loss with the Plus 4's.

Mike

I've heard several reports that the Bosch Platinum plugs don't do well in the 3800's. NGK's or AC Delco's are much better.

-- markwb

Are the NGK's better than the Delco's? I am looking at plugs for both cars...the 3800 and her 3.1 in the Grand Am

If I were you, I would stick with whatever the factory put in them. They work best.

Ian

I've seen those, I dont see how 4 electrodes help, since the spark will only happen between whichever of the electrodes is closest to the center node. After that, all the other ones only serve to do is block an even propogation of the fuel/air charge's explosive wave front.

They worked fine in my '95 2.3 but I switched back to OEM plugs. I can't remember why..... but anyway, they worked fine, but certainly didn't provide any miracles. I'd follow IAN's advice, the OEM's should work best.

Tony

And aren't as outrageously expensive either.

I put thiese in my 99 sunfire 2.2 and changed back to delco in about 500 miles. They are not worth it at all!!!!