For my 77 Carrera 3.0 (WOR) which system is better for my ignition and why? MSD is a lot cheaper($200 vs $300) but Permatune seems to be much easier to switch. Is a MSD unit difficult to install or am I thinking it is more difficult than it actually is? Sorry for the repeated ignition problem questions. As problems occur, being a beginner to all this I need to learn everything from the ground up. Thanks Tom and John for your previous help.

 

The Permatune is certainly an easier installation - apparently plug and play. I don't have any personal experience and you'll probably get several responses from those who do but, if you search this board for "Permatune", you're going to find mostly negative comments.

I've recently been investigating the MSD as a replacement for my Bosch CD for two reasons:

performance improvement - I've had good
results on (non-Porsche) road racing cars and
have heard good things about driveability and
performance improvements on street 911s

when the Bosch CD dies (it is 22 yr old), the
MSD is a much cheaper replacement.

According to the MSD tech staff (915-855-7123), the MSD completely replaces the Bosch box and uses the existing pickup in the distributor. You will need the MSD tachometer adaptor kit and a different coil. From what I read, a new distributor cap, rotor, plug wires, and opening up the plug gap a bit would be a good idea too. Lots of folks have made the switch and it apparently isn't difficult.

 

I dont have any experience with the MSD but I do have the Permatune coilless unit on my SC. the instal was straigt forward and it has a completely factory look. Performance-wise I have seen no improvement. My plugs still foul regularly and I dont think I gained any horsepower. My car has equal length headers, no cat, and headwork(for reference). Good luck,

 

I just installed an MSD6-al and coil in my SC. I have only started it once so I can't comment on performance. The install was time consuming. I had to fabricate up a bracket to hold the unit and the coil. It just fits.
Dean