[Early_S_Man]

Kevin,

Sure, Porsche started putting an exceptionally reliable system on 906E's in 1967 ... called BOSCH! Dual ignition equates to multiple sparks, right?

You aren't the only person on this board who questions MSD relibility ... besides myself!

John Walker does NOT recommend MSD on SC engines ... says he has a whole box of failed units removed from problem cars! Bosch units fixed the MSD problems.

I have personally never seen any difference in performance between working Permatune and Bosch CDI-units with 'clean' wiring and connectors! So, with that said, why not clean up your Permatune installation and return your ignition to original factory performance ... which I assume was fully satisfactory, 30 years or so ago???

Is your Permatune box blue or natural anodized aluminum finish?

For any owners of cars with marginal or misbehaving Bosch CDI-units ... the following will ALSO serve as an electrical 'tune-up for YOUR CDI!

To assure proper operation of your Permatune unit, I recommend the following steps be taken:

1. Clean the braided ground straps at the coil, distributor, and relay/fuse/regulator/CDI-unit panel. Run an additional ground strap -- at least 12 ga. wire -- from the upper left mounting bolt of the Permatune unit to the leftmost mounting bolt for the MFI filter mounting bracket ... clean the body panel and corner of the Permatune box where the strap will attach! Apply Dow Corning 4, 11, or 112 to the strap connections.

2. Clean all four 1/4" Faston tabs on the Permatune box ... shiny-bright!

3. Clean the Red 12 Volt supply wire to terminal 'B' of the CDI-unit plug at the fuse block ... loosen, remove, and clean set screw. Then, remove wire end and clean. Reassemble with a coating of silicone grease.

4. Clean the FOUR individual female Faston connectors that connect to the Permatune box. The three wires in the rubber/plastic boot can be carefully slipped out an inch or so to work on them ... dip, spray, or brush on a bit of vinegar onto the female Faston and let sit for three-four minutes. Rinse off with distilled water, then isopropyl alcohol and let dry. Test for the presence of 12.5+ Volts at the CDI-end connector of the Red wire with the ignition switched on!!! Test for a snug & secure fit onto a new 1/4" tab. If loose or marginal ... crimp the siodes of the female connector slightly to increase the tension, but DON'T close the gap entirely!!! Test the fit on the new tab again. If snug and satisfactory ... proceed to the next connector ... when all three 'captive' connectors are clean, pull back down into the rubber boot. Apply silicone grease to all four and re-attach to Permatune unit.

5. Clean the 1/4" tab and connector on the Black/Violet wire at the distributor!

6. BE SURE that you are using the proper & correct Bosch 0.221.121.001 or 0.221.121.006 coil for the CDI-system, and that the terminals and connectors are clean and snug! Test the coil for primary side resistance of 0.4 to 0.6 Ohms, and secondary resistance of 650 - 780 Ohms at room temperature.

Test your system by starting the engine and doing a test drive ... I believe you will find full power performance again at your disposal!