Sparl Plug Wires

Saffs · 06-06-2002, 07:45 AM

I need an answer to this one quite quick - no time to search extensively. I need some spark plug wires w/ Buru (sp) connectors, the car is a '73.5 T w/ CIS. In the past on CIS 911s I've gone for ones with the braided wires: do I need to, though? I'm guessing the braided wires are to reduce interference and prevent crossfires - causing backfire and exploding airboxes? But is it really necessary? I have a pop off valve too!
TIA
Anthony

Oldporsche · 06-06-2002, 08:17 AM

I believe that the braded wires have been found to unnessarily drain your bank account.

Good luck,
David Duffield

Early_S_Man · 06-06-2002, 08:53 AM

Saffs,

Many CIS cars have worked just fine with the early replacement sets, and I have yet to EVER hear of a crossfire or backfire problem turning up after the early wires were installed! Just as a bit of confirmation ... the '74 factory brochure shows 2.7 CIS engines at the factory with early-style wire sets!

pwd72s · 09:20 AM

Anthony, Warren just made a great post on how to use a multitester on the Beru connectors...it's probably on page 5 or 6 by now...but by doing this, you might save a few bucks, buy the wire only? Gee, with a few "pretty pleases", he might even tell us how to connect raw plug wire to the factory connecors?

Edit: Here's the string with Warren's post on how to test...
Beru connectors, are VW the same?

Rich911E · Rich911E's Garage

I just got a set from Alan Johnson here in San Diego. They are 8mm wires with the nice connectors for (get this) sixty dollars. I was skeptical, but myself and KeithO64 both got a set and they work great. Can't beat the price.

Rich

Early_S_Man · 06-06-2002, 10:43 AM

Paul,

Thanks for the kind words! Yes, the shielded ignition cables can be rebuilt with bulk Name-brand spark plug metal-cored wire from Belden, Packard, AC Delco, Autolite, etc.

The early Beru connectors have a male screw inside the dust boot that is quite similar in profile to a wood screw ... and it just screws into the stranded-wire bundle of any metal-core ignition cable. The later CIS-type Beru connector used on the shielded cables, and the only one that is still officially available from Porsche ... has a female thread machined receptable that a 911.609.310.00 crimp-on connector with male screw tip screws into.

To disassemble the old cable ... just take the Beru connector in your left hand, and grab the wire firmly with the right hand as close to the connector as possible, and quickly twist the wire counter-clockwise to break the connection. Installing the old=style connectors is just a matter of 'starting' the screw in the center of the stranded-wire bundle and firmly screwing the wire into the threads. For new-style Beru connectors the new bulk wire must have a new threaded brass threaded tip crimped onto the end. Mercedes and Porsche dealers have the special crimping tool, or a crimping tool for coaxial cables using RG-58/U 50 Ohm coax (smaller than the typical TV cable RG-6/U or RG-59/U 75 Ohm coax) can be used. an additional crimp is needed to connect the stranded wire to the tip, and Porsche uses a special 3-lobe crimp die. With copper-core bulk wire I drill the end of the brass tip with a carbide #55 wire drill bit so the connection can be soldered. That makes a satisfactory, strong connection that is superior to a crimp that may pull out when unscrewed in the future! Old factory-crimped wires may pull out when disassembled! The tip will then be rather difficult to remove, and the Beru connector or distributor connector MAY have to be replaced!

Here is an earlier thread with detailed discussion about rebuilding the cables ... which I have just bumped:

Ignition Wires