Going to MSD System, What tach adapter and hook up Options

[DonTraver]

The biggest problem I've had with my 6 had been the original CDI ignition system. I've finally had it with 40 year old tech.

I've decided to go to MSD 6 ignition. I'm still running points with the stock Bosch distributor so I'm going to need a tach adapter, if I've read the MSD papers right it's a current triggered tach system.

So has anyone done this conversion to MSD and what tach adapter did you use and what hook up, anything to look out for? I've also heard a long time ago about sending tach to I think Hollywood Speedo(?) to have tach rebuilt for a MSD system, any info on that?

Thanks in advance for any help.

Anyway, that's about all.

Later, Don

[john rogers]

Hi Don, here is what we did with my race car which would be similar to your setup. I bought the MSD box and tach adapter from Summit racing and the tech guy knew what adapter to get when I said Bosh distributor and porsche tach. I also bought their electrical gizmo that eliminated any electrical interference with the radio (mine was the race two-way radio but your incar stereo could be affected. We also eliminated the points and that was great for maintanence purposes. I can not run the stock wires anylonger (solid core) so Blackforest had a shop make some of the 8mm race wires with Porsche connectors on the end that work great. I finally went with an MSD tach so the tach adapter is not needed but it is still in the circuit anyways.

[Allan]

I didn't need a tach adapter with the MSD.

Worked just fine.

[jasons]

With my 4 cyl and a Pertronix, and an 8920 tach adapter, this is a diagram I made and had verified by some MSD tech on their support forum. I used the 8920, because I happen to have it on hand. However, I think either will work but the wiring may be different....

[Aaron Cox]

Don,

you can get away without a tach adapter....

which wire does the MSD use as a trigger signal from the dizzy? you dont even have to use the tach drive on the box.....

TEE into the signal wire from the dizzy to the box, with a piggy back spade, and it SHOULD WORK.

i believe the white wire is the Tirgger signal to the box

AA

[DonTraver]

I'm using the white wire to the distributor. I tried the piggy back, didn't work. Also tried the tach output from the MSD, didn't work.

Allen, I suspect that your tach has been modified to run with the MSD. Did your 6 come with the MSD already installed or did you install it?

Jason, thanks for the print, think I'm going to need the 8910 adapter for points

Later, Don

[Allan]

Allen, I suspect that your tach has been modified to run with the MSD. Did your 6 come with the MSD already installed or did you install it?

Mine was running the stock CDI when I got it.

[DonTraver]

Allen, it had the stock cdi? So how did you hook up your tach? I don't get it right now, not unusaul. If I've read the prints right, the tach wire is the purple and black wire.

[Porcharu]

The biggest problem I've had with my 6 had been the original CDI ignition system. I've finally had it with 40 year old tech.
...
Later, Don

So your moving to 37 year old tech? Get 3 or 4 of them - you will need them as they die on you. I don't mean to be negative but I have had nothing but crap luck with MSD products. My old boss had a huge (like 1/2 a cubic yard) of MSD 6AL's that failed on his old race car. (IMG:style_emoticons/default/barf.gif) (IMG:style_emoticons/default/barf.gif)