[RedZMonte]

I run Plane jane AC Delco's or NGK's... have had nothing but good sucess with them.. +4's are Junk... Gimick... ect..

S

[GTP091]

Originally Posted by 3100 MPFI

yes, I have used the bosch plugs in a twin cam. When I built the engine in my 1995 I had to drive it with bosch 4's until I could get to the parts store. It was REALLY bad.

AC DELCO rapidfire plugs for a 1991 TWIN CAM, the part number is 12

Rapidfire number 12 is what you need.

Don't listen to what the people at the parts store tell you. When I worked for Pepboys, they would tell us to push the Bosch +4's and when I refused, they started threatening to write me up, and fire me. Also, don't trust the parts store when they tell you the plugs are PRE GAPPED.

I bought the Bosch +4's because of research I did on spark plugs. At the time these plugs seemed like the cats ass so I happily paid for them. They certainly didn't say anything about wearing out in a waste spark system. They were advertised as outlasting and outperforming, to bad.

I still haven't found the rapid fire plugs at a store yet. I did some research on the AC delco website and it looks like the rapid fires use a platinum pad but the electrode is more conventional. It would seem to me that these plugs would still overheat in a waste spark DIS and end up like the +4 Bosch platinums, with the platinum pad worn away? What do you think? I might just go with regular delcos or the V-Groove NGK's but they seem like more of a gimmick than all of these plugs; I still remember the v-groove commercials.... http://www.acdelco.com/parts/sparkpl...e-platinum.jsp

[Superdave]

Originally Posted by GTP091

http://www.acdelco.com/parts/sparkpl...e-platinum.jsp

Same link i was about to post.


I ran them in a healthy 2.8 Cavalier several years ago, they lasted a month or so. I switched it back to standard Delcos and it lasted for another couple years before a rod started knocking.

[mrl390]

I was pulling a random misfire code on my car so I changed my plugs. I bought single platinum plugs to replace what I thought were the stock plugs. I ended up pulling double platinums out of the car. There was no evidence that I could see of anyone having done the plugs before, unless they were able to do it without removing the plenum. What DID these cars come with from the factory? When I put in the new single platinum plugs, gapped to .045, I got rid of the random misfire code and the car runs just fine.

[timg]

I generally go with Rapid Fires or standard AC Delco plugs. The only problem is that they seem to wear out quickly. Platinum plugs should last longer.

Tim

[Superdave]

I made the mistake of putting Autolites in the wife's GAGT last year.. started to get a random missfire after a month but it cleared up. It's been fine untill today i could feel them getting a little weak.

She's getting a fresh set of iridiums tomorrow.