Posted by Frank H on January 27, 2000 at 21:52:56:
In Reply to: Re: Two Thumbs Up For Bosch Platinum (NOT) posted by Walt Barie on January 27, 2000 at 16:43:12:
: : I've had my e12 for almost 6 years and have always used Bosch Platinum spark plugs. Well anyways, I took the car in for a tune-up and the guy recommended I start using NGK plugs, I was a little hesitant at first but gave them a try. A week later the car would not idle and hesitated upon acceleration, I freaked out, what the hell could this be! I decided to pull the plugs out and the ceramic insulation around one of them had cracked causing it to bridge over. I went to Pep Boys and picked up some Bosch plugs and they cured the problem. I would just like to recommend Bosch Platinum for anyone who hasn't tried them.
: : -Jeremy
: : 80' 528i (my baby)
: : 80' 528i (parts/project car)
: If the list has archives that go back far enought you can find a posting by me with the problems that I had with normal Bosch platinum plugs.
: To make a long story short. The little center electrode disappeared on at least one of my plugs causing a very difficult to diagnose miss. I also had one go bad in the 320i that I had at the time. It may have been a quality issue becuase this was a few years ago however I have never had a problem like this with any other plug that I have ever used in my life in any car including the normal Bosch, Bosch Super, and Bosch Silbers.
: One thing that Bosch platinum plugs do is because of their small electrode diameter and resulting lower breakover voltage (than a normal type plug) is to coverup other ignition weaknesses. At one time my 528i ran decent on Bosch platinums but like crap on new Bosch Supers. I changed the spark plug wires and low and behold the car now ran fine with the new Bosch Supers. So if you car runs noticably better with Platinums compared with new normal type plugs then you probably have a weakness in your ignition system that should be fixed.
: So I really don't think that the Bosch platinum plugs are worth the extra money and after my personal experience I don't trust them. However I'm curious about the +4 plugs since they should expose more of the gap to the combustion chamber.
: Regarding platinum plugs, I've had good luck with Autolite double platinums in American cars. They seem to last forever but I don't know if they have the exact heatrange for a BMW.
: Walt Barie
: '80 528i
: '82 320i
: '89 VW Jetta
I would have to second Walt's opinion of Bosch Platinums in E12's. Platinums work fine in newer cars with weak ignition systems. My old
Honda civic really liked them (added 2-3mpg when I used them) BUT older cars German/British etc especially those that might burn a little oil
will foul Platinums very easily. This could be due to the plug having a lower arch over voltage requirement.
I have used the Plat +4 in my Audi quattro coupe. Even though they were not recommended for a turbo application. The biggest difference is
the car seemed to start a little easier. I never had any real benefits or problems otherwise.
As for multiple prog standard plugs (NGK/Bosch)--I have used them as well. They seem to last much longer (but also cost as much as $9 each!).
This is the plug the quattro is supposed to use. Supposably they are better in turbo applications due to the three possible paths for the spark
AND better heat absorption.
Frank