MSD 6AL How to wire
 

Guys I am about to order an MSD 6AL 6420 with rev limiter (I assume this is the one which is adjustable) and want to know how easy it is to wire up to replace original Bosch CD unit (1982 3.0 SC engine)

Simple
 

Very easy install, i just installed the 6 btm in my car, took about 2 hrs. And yes! The single green wire going to the distributor is actually 2 wires, splice into this one at the ignition box end.

Tim

Green to green on the magnetic pick-up. Just tap into the existing wires for the power and tach. Tach wire is purple and black. Don't bother taking a wire all the way to the starter or battery. The 3 fuse block has a nice unswitched 12 volt supply with a 20 amp fuse.

-Andy

And several years later, the wiring diagram is printed on the unit, if you misplace the paperwork.

Pay attention to the requirement of the signal wires from the distributor must be run separate from the remaining wires from the MSD box. Don't run everything in one harness or there is a chance of interference and you will get a corrupted signal to the box. That will change the timing at high revs and make for a bad day. Other than that, adding an MSD is one of the easiest thing you can do to your Porsche, at least that's my experience.

Lindy

And so the next question is will I need a tach convertor for an 82 euro SC? Whats the better buy the 6al or 6al-2?

MSD Wiring.....
 

When I installed an MSD 6A in my SC, I just put male terminals on the wires and plugged them into the factory master plug that came off the Bosch CDI unit. Very easy install this way and will be easy to put back stock later if desired. Other than the six wires in the plug, you will need a power lead (I used the starter as a power source) that is fused, and a ground. I ran the ground to the frame and then to the engine just to be sure that I got a good ground. I turned the rear window relay horizontal and mounted the 6A just above it running front to rear of the car. That way the stock cover will cover most of the MSD unit. I also replaced the 3 fuse panel with a 4 fuse panel to make a fused connection for the main power lead to the MSD. Hope this helps. Good luck with your project!

Most 78-83 SCs don't need the tach. adapter. I said most because some need it, some don't.

I am still not sure if I am going to order this unit or not, cant seem to find difinitive evidence of whether I need a tach adaptor or not also been on MSD forum and a lot of people complaining of issues with the units. Can someone put me out of my misery and recommend this change or should I leave well enough alone dont want to plagued with ignition problems>...

Let me help, add up all the problems on the MSD forum and divided that by the MILLIONS they have sold in 40 years of making this unit, the number of failures will be very low. Buy the tach unit but don't install it and if not needed, send it back.

Never, ever had an issue with an MSD product. I've used it on my Porsche and many other V8 builds. You have to read and pay attention to the directions and, if you do, there will be no problems. Highly recommended!

Lindy

Ok James Brown you have convinced me it is now officially on my xmas present list...

"I feel good"

:)

I know this is an older thread, but what kind of improvements did you find with the MSD? I have the box and matching coil pack ready to install. Just kind of wondering what I can expect to gain if anything from this? I purchased them both for another project and thought I might just install them in the Pcar if it's worth the upgrade. Thanks guys.

Msd
 

After adding an MSD 6A and coil to my SC, it had a smoother, stronger idle and ran better all the way up to redline. Worth every penny!

If you want a plug and play solution with a dyno proven increase in power, our CDI+ units work with all the original Porsche components. The units are also mappable for ignition advance and have many other features such as a shift light output, soft and hard rev limiters etc.

See www.classicretrofit.com for the technical manual and the independent dyno test cell report.

Looks really nice bit of kit, Jonny - great classic look too.

(Liking that fuse panel as well)

Cheers
Spencer.