Ignition Upgrade questions...
 

I've got a stock '78 911SC. My mechanic says my ignition control unit needs to be replaced, because it is working intermittently.
(This is my version of his words, so please excuse statements the may sound incorrect)

He suggested Perma-Tune, but says he's used MSD before as well. I'm read alot of threads, and sounds like overall people seem to lean more toward OEM or MSD slightly over Perma-tune. The idea of an upgrade over OEM is appealing to me, but the reality is that I have to sell the car soon, so I won't get to take advantage of it much.

MSD is the least costly of the 3, but I'm concerned about mounting. Will this be tough to mount in place of the stock CD on a 78 SC?

Do I need the Rev limiter version?
I believe that my car has a rev limiter already, it's just not adjustable. Will I loose this if I go to the MSD 6200?

Do I need new ignition wires? My mechanic said it wasn't necessary, but to get the "matching" coil with the ignition system I choose.

With the MSD, do I need the Tach Adapter for a 78 SC?

Any other words of wisdom regarding this topic?

How about just this one question...
Does anyone know if I'll need the tach adapter if I install an MSD 6200 on a stock 78 SC?

Ignition Replacement...............
 

I installed an MSD 6A unit in my '80SC about 4 years ago. My car already had an internal regulator alternator so all I had to do was rotate the rear window defrost relay 90 degrees to make room for the MSD. I used crimp on male blade terminals on the MSD wires and simply plugged them into the 6 wire master plug. I did not need to use a tach adapter. The main power comes from the +12v terminal on the starter and I ran a ground wire to the mounting base and then on to the engine. Here is a picture of my installation:http://forums.pelicanparts.com/uploa...1215745794.jpg

The stock wiring cover mounts over the MSD using the stock bolts. The money that I saved by using the MSD instead of a rebuilt Bosch CDI went into a new set of Magnecor plug wires. This is an easy mod with good results. Try it, you will like it! Good luck with your project.

Everything I've read is that there's no rhyme or reason as to which car needs it and which doesn't.

So, buy it (it's cheap). Try without. If you find that you don't need it, then sell it as new here, and make 95% of your money back.


I also would suggest getting the rev limiting version, so you don't have to trust the somewhat archaic mechanical rev limiter in your stock distributor.

Have your CD unit rebuilt?