Which msd tach adapter ?

[michel richard]

Do I need ?

I have a 2.2 E on which I have been running stock Bosch electronic ignition. I'm putting an MSD ignition in, and the engine runs fine.

I initially mistakenly wired the tach wire to the coil, but got the 3X and 2X error at low rpms. I tried connecting the wire to the MSD box, but then the tach does'nt work.

I've researched the this board, but posts are not always clear as to which ignition is in the car being discussed.

So, I understand that the tach adapter 8920 would be for 3.0 engines that have the magnetic pickup distributor (and in which there are not points), while the 8910 adapter would be for my setup as well as for someone converting from the earlier straight points and condenser ignition.

I have points in my distributor, but the stock system uses these only to generate a signal.

Is this all correct ?

TIA

Michel Richard

[Kevin G.]

Michel -

I am running a 2,2S motor in my 72T Targa, and recently replaced a Permatune ignition with the MSD 6A unit. I had previously replaced the points system with a Crane optical system, so the points are long gone. When I bought the MSD, I also purchased the tach adaptor - the 8910.

Once installed, I connected the lead from the Crane to the MSD 6A unit without using the adaptor and the tach runs just fine. Again, I no longer have points, but I can't see where there would be a difference - it's the same wire with the same purpose. Maybe the tachs are different between 70 and 72.

You may wish to try the connection once again to the tach terminal on the MSD unit. If it still doesn't work, you can have my unused tach adaptor for the cost of shipping. (I stupidly threw away the receipt, so I can't return it).

Good luck,

[michel richard]

Is your tach adapter for sale ?
michrich@videotron.ca

[michel richard]

Kevin, I did'nt read your post to the end before my post just above. I'll be in touch.

Cheers

[jabb]

Hi michel richard
I would think you need the 8910.... I used the 8920 becuase I have the magnetic pickup and an 82 tach.

Are you using the White wire in the MSD this is where the 8910
adaptor is designed to interface with.

The 8920 has 4 wires....
Red to switched power.... blcak to ground..... purple to the existing tach wire..... and a white wire that plugs into the MSD tach lead.

Hope this helps............

[CamB]

I agree - your tach should work without a tach adaptor (the 8910 if you do need one).

Was the black/purple wire initially hooked up directly to the coil (with your old ignition?). If so, it may not be the original tach.

(edit) It should have gone to the CD box or the speed switch looking at the wiring diagrams. You could also try connecting the tach to the points (the MSD white wire). Basically if the tach adaptor is installed, it gets a +12v signal with one wire and the other is hooked onto the points with the tach - I think it juices up the signal for the tach.

[Kevin G.]

Michel -

Sorry, I couldn't arrange shipping until this AM (Tuesday). It went out USPS Priority from Chicago. Total Cost $6.35 US. You can find my mailing address on the shipping label. Hope it works for you.

To all you Pelican Heads from Chicago - this is my first trip here and I am IMPRESSED! Chicago is a beautiful city, and I can't believe how clean the downtown area is! The weather has been fantastic, hope you are all enjoying what I understand is unusually good driving weather instead of being stuck in a conference.

Good luck, Michel

[michel richard]

Thanks,