Bosch Platinum+4 vs ACDelco Platinum Rapidfire spark plugs!
 

I installed the Bosch Platinum+4 plugs in my 350 '91 Formula about several years ago. I have put on just a couple of thousand miles and checked them out yesterday. The car has been running fine, but on the four electrodes, 2 of them were dark brown and 2 were light tan. I am thinking off just replacing them with the AC Delco Platinum Rapidfire plugs. Anybody here have any comments about how they run or did you notice any difference? I also have an MSD 6A box with the Blaster Coil.

i have regular ac delco in my car and it runs fine i would go with those

i have reg ac delcos in my modified motor and they run perfect. i used bosch in my cavalier once. ran like crap, horrible gas milage. put ac delco back in and it was better than new. that car used to out run a passat vr6.

Rapid fires are a little pricey and from what I hear, not as good as they use to be. I would just go with NGK's.

The only thing I picked up on these plugs were that they went to a Platinum Tip to last longer. I also read that they are actually made by NKG. Who knows? I found a set at PEP BOYS for $3.49 each, so the price is only about $1.50 more than the standard plug. Plus it's a HUGE PITA to install these plugs in the number 6 & 8 spots, you have to twist your arm over the starter in ways it was not meant to go.

I run E3 spark plugs in my truck and I have no complaints. They seem pretty good.

I know, its not all that bad. I have had many a thirdgens before.

but 3.50 for one plug ... wow

yea regular ac delco is the way to go.

I wanted what I thought were the best for the Bird and spent $6.00 a plug for the BOSCH Platinum+4. Figured I would never have to change them for the next 100,000 miles or I die FIRST. LOL

I personally use the Autolite AP104s in a DD and the AR103 or AR104s for racing applications. Did you check the gap on the plugs when you took them out?

Those Bosch Platinum+4 plugs cannot be gapped. I changed them all to the AC Delco Platinum Performance plugs. With the headers, what a bitch to change them since the ACDelcos were 1/2" longer. I have a cut down spark plug socket, but still took waaaaaaaaaaaaay toooooooooo long.