MSD IGNITION Q'S

[jimmcd]

I have a 912E (I know, this is a 914 forum-but it seems to get more traffic), and I recently installed an MSD ignition (6A). How do I get my tach to work???? I tried the white wire, neg. side of coil, and nothing. I just got the tach back from VDO so I know (I hope) it's not that. Do I need the tach module for the ignition? I'm running points.

[HarveyH]

I'm not sure about the MSD kits, but Crane makes two tach adapter kits for their CD ignition modules. The choke type (the cheaper adapter) worked fine on my car. Instructions are included with the kit. The choke type is just like a transformer with no secondary winding. It's just a coil of wire around a laminated iron core. The more expensive unit has a circuit card.
Harvey

[DonNewton]

As you're driving a 912E, you'll need an electric tach (as seen in the 911SC and up). I realize that "electric" is not the correct term, but for the purpose of this response, it works. Anyway, I converted my 6A MSD on my race 914 to the (God help me) NASCAR 7AL2, and needed to pick up an SC tach. Amazingly, as soon as I had the tach in, it worked as it's supposed to.

[PeteD]

I have an MSD-6A on my 914 and can tell you with certainty that you need the "MSD 8910 white wire trigged tach adapter" that MSD sells in order to get your VDO tach, that used to just connect to the coil, to work. It is a small, transformer looking thing that takes the signal out of the MSD unit and makes the waveform compatible with the VDO tach. I don't know if Pelican stocks them, but you can alternatively get one from JEGS or Summit.

[John Rogers]

The previous post is right. You should get the "tach adapter" which is basically a little transformer. You need it with most stock Porsche tachs and I use one with my Autometer tach just to isolate it a little from the high voltages and frequencies of the MSD unit. You should find the engine runs cleaner and smoother with the MSD box instaed of the stock system. Good luck.

[iustasail]

I just instaled the MSD-6 unit and had to use the Tach adaptor. If you chose to get one do not try to plug the Tach guage sending wire into the MSD box. The plug in the box is only for the modern electronic tach. You will need to splice the tach sending wire into the white MSD to Distributor wire along with the white Tach Adaptor wire(the red Tach Adaptor goes to a switchable 12 V source)the Tach adaptor will then act like a little coil thus providing the 80+ volt wave required to run the old tach. I had a lot of trouble getting it to work because my directions were wrong but if you set it up as above it should work quite well.