After looking at it recently, a Porsche certified mechanic has told me that I may want to think about a new distributor cap and rotor on the converted twin plug Kremer modified 1981 Euro 930 I recently bought. He says these parts are OK, but not great.

I have just found out the price on these- about $1,100 for both, since they're discontinued RSR parts. Wow. I see on the net that stock non -twin plug 930 caps and rotors are about $20 to $40 for both. What a difference. I owned a 1982 Euro 930 several years ago, and amazingly never got into any real mechanical issues with it before I sold it for a small profit.

I seem to have these options, in talking to a few different mechanics at different companies:

a. pay the price and stick with the RSR parts as they'll last for quite some time

b. convert over to a crankfired system, and sell my 2 HKS component CD boxes and stock distributor converted to RSR to recoup part of the cost (the Porsche dealer says the CD boxes are homemade by Kremer but used good HKS parts). I've been told I can maybe get some fair money for the CD boxes and the distributor to offset the crankfire cost.

c. see if the rotor can be filed and helped out any (not sure what could be done for the cap)

The car is running quite well now, so I'm tempted to go the lowest cost route- choice C. Any advice from anyone who's gone down this path before? Thanks.

 

I would try cleaning them first and see what happens.No sense in spending the money right now. Make a plan and put it in place for the future. The cost of the cap is no joke. We do digital map retard systems for not much more than that. Someone should pick up the slack and remake these. It would be worth the tooling. We use the crank fires with great success and they work well. Here is a pic on a car we are finishing up.

 

There are other choices to be had. Install a single 6 pole Distributor into the stock location, and run a second off the back of the 1-2-3 side. Then you can run your 2 CD units and your good to go. Possibly less $ all round.

The distributor in the stock location needs to have the Reluctor trigger installed to go with your CDI units. The Distributor Cap and Rotors are very inexpensive, off early 911 T I think. Around $ 15 each or less.

 

m42racer, I don't think your solution would allow for boost retard. Wonder if you could rebuild the RSR cap with a couple of normal caps, might be worth a try.

 

Not sure that the RSR Distributor had boost control. Maybe use the Turbolink to contol the Boost, which also has the boost/Igntion retard function, and the extra Injector drivers. I understand the Turbolink will intercept the Reluctor signal from the Distributor.

The Ignition retard would be important on a Turbo engine I guess.

 

M24, you would also have to relacate the turbo sump if you ran ah la 956/962 style. Someone makes a 964 type conversion, but most are very costly.

 

I vaguely recall another thread where the someone successfully used
a Ferrari cap and rotor instead of the RSR cap and rotor. I think he said
he made an adapter plate to mount on the stock distributor and
mounted the Ferrari cap on the adapter plate. Has anyone else
tried this?

 

The conversion still allows the pump to remain just like the 962 did.

With the cost of the Cap and Rotor (unavailable), this conversion makes a lot of sense. Also makes everything very simple. The Ferrari cap and Rotor has been done, but these are now very hard to find also. The shaft needs to be modified etc. In the end, it all will cost $, its just whats available when you need it.

 

LOL,...I have new RSR caps and rotors,...

How many do you need?

They are not cheap, as you can imagine.

 

Twinplug930,

Clean and use the original cap and rotor. The manufacturing tolerances are actually pretty loose on these parts. With the cap, use a NEW single edge razor blade and carefully scrape the concave surface of the poles, after scraping use a new or very fresh stainless steel brush (tooth brush size available at hardware store) to finish up cleaning the carbon build-up. On rotor, use a fingernail file as a mandrel with tightly wrapped 600 wet and dry sand paper (use wet with water) and gently sand the surfaces. Be particularly careful not to round of any features, keep all corners as sharp and crisp as possible.

Here is the most important piece of advice you can receive on this subject: DON'T DROP THE PARTS !. They are heavy and very brittle and this is the main reason people have to replace them.

Interesting story on the lack of new caps and rotors told to me by somebody very high up in Porsche kingdom. Seems that Bosche decided to save money on manufacturing and sent cap and rotor molds to Portugal via boat. On the way boat sinks, molds now at bottom of sea with old German submarines in straights of Gibraltar. Bosche has no interest in retooling for parts that only sell 100 per year.

End of story ?, no. The good news is Andial now has replica rotors (shop price is $485) available and replica caps will probably be available next year. I know this because I am the guy making them for Arnold and Dieter. The replica rotors are now installed in everyday drivers including my own turbo, and are working fine.

Cheers, Paul 930 RSR thing in Cashmeir

 

Cool story

 

Thanks everyone for the excellent advice. I know tons more now about this issue than I did a little while ago. I'm going with the filing attempt first, then I'll decide from there.