<VV> Strange power loss problem

[Bill Elliott]

There are widely varying experiences with Bosch Platinums.   While I am 
a HUGE Bosch fan (and run only Bosch or NGK plugs in everything I own) I 
happen to think these are not very good plugs.  They _seem_ to require 
more voltage to fire for a given gap.

A few folks (like you) seem to have no problems at all with them. Most 
of these folks are running a hot coil and electronic ignition. Some 
folks (including a couple of of my Corvair engines) can't even get the 
engine to idle on a set. Most folks are somewhere in between... I 
suspect a marginal ignition system is the real cause and that should be 
addressed...BUT if that marginal system fires Supers fine yet has 
difficulty with Platinums, then that (to me) is more evidence that the 
Platinums need more power to fire...and that you are giving up a "margin 
of error" in the ignition system by using them.

I can give you the long and torturous story about my experiences with 
them in my Audi Quattro Turbo Coupe (which had a hot ignition but which 
was VERY picky about plugs... I tried virtually every plug in the Bosch 
lineup and the base Platinum was by far the worst... yet my normally 
aspirated 4000 Quattro ran great on them.) At the other end, the BEST 
were the Bosch Platins... a _real_ platinum plug with a large center 
electrode... and a $25/per price tag. This suggests to me that the tiny 
center electrode in the Bosch Platinums (and not the fact they are 
platinum) is the real issue.

I can also give you many, many stories from when these were THE plug and 
I was working part time with a Corvair-only resto shop... at least once 
a week someone would come in with a poor running Corvair. #1 cause was 
by far the platinum plugs... cause #2 were ill-adjusted carbs....

In _most_ Corvairs, changing from Bosch Platinums to Bosch Supers (at 
1/3 the price) yields an improvement in driveability and power. In some 
Corvairs, there was no change. In no Corvair (that I am aware of) did 
changing from Platinums to Supers cause any _loss_ in performance.

So in summary, if (1) many folks have issues with Platinums and (2) 
nothing is gained by running Platinums and (3) Supers are a fraction of 
the cost, why would anyone _want_ to run Platinums in a Corvair? 

I would suggest that you try the same challenge that I've made to many, 
many other Corvair owners. Invest $6 in a set of Supers.  You _might_ 
find that your car doesn't run as well as you think it does... or at the 
worst you might find it runs just as well on cheap plugs...

Bill


aeroned at aol.com wrote:

> <Snip> 
>
>The other typical "stumble" situation that will give the same sort of symptoms is the use of Bosch platinum plugs. 
> 
><Snip>
> 
>Bill,
> 
>I find your statement interesting. I have Bosch platinum plugs, a pertronix I, and a high output coil on my 140. I haven't had any stumbling problems, certainly nothing close to what was described, (other than hitting deer). Could you provide some details on what you believe is wrong with these plugs?
> 
>Ned
> _______________________________________________
>
>  
>


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