Ignition: New Electronic Dist. WITH Non-working Tach.

[StudeRich]

This question 4 days ago did not get answers on the recent Electronic Dist. String, so I am re-posting it here.

Did any of you connect a Analog, Stock Studebaker Lark/Hawk/Avanti Tach. to one of these Electronic Chicom Dist.'s?

Mine did have a Tach. Wire on the Dist. so I wired it there, not to the Coil Negative Post as a Factory points Dist., but the Tach. does not work on my Avanti that DID work.

I see that the instructions call the wire to the Tach. a "Digital Tach. Wire".
I wonder if they are not compatible with our Factory Analog Tach's with Sending Units?

I know there WAS prior talk a while ago about this here, but I don't remember the answer.

[StudeRich]

STILL, no one who has an Electronic Replacement Distributor with a factory Tachometer has seen this request for a little help?

[Videoranger]

Rich, I'm thinking you'll need a signal adapter. I haven't made the distributor swap, but I'm thinking about going that route. I did a google search of electronic distributor and analog tach. Sounds like using the factory Stude tach might be do-able with the right adapter and hookup.
http://www.marshallinstruments.com/f...tail.cfm?id=29
also came across this, it's from a chevy forum, but the principle should be the same:
You need to install a tach filter between the tach wire and the distributor. The waves that an HEI distributor puts out cannot be properly read by MOST analog factory tachs. I have heard (but never personally seen) of very few instances where a tach worked without any modification. Anytime someone buys a harness from us that is modified for HEI, we typically inform them that they will need to put a tach filter in line on that wire. Accell and Mallory both make a piece, but most any Camaro or Monte Carlo or other HEI vehicles from the 70's/80's will have a tach filter on them if they are equippped with a factory tach. A junk yard trip is possibly in order. They look like a condenser with wires coming out of each end....1 to the coil/distributor cap, the other to the tach wire. They are a plug and play deal. They show up on ebay pretty regularly and can usually be bought for 35-50 bucks. Good luck!
A response from an actual Studebaker owner that has gone this route would sure help, as there are some variables dependent on the application and what electronic distributor is used.

[bezhawk]

I had to use this when I put a hall effect triggered ignition in a Stude. MSD Ignition 8920 MSD Magnetic Pickup Tach Adapters | Summit Racing

[E. Davis]

I have the mopar EI conversion and the tach didn't work. I called Summit and one of their techs walked me through a wiring procedure that fixed the problem. Might want to give them a call as they are really knowledgeable on those things.

[StudeRich]

Without a Degree in Electronics, mine is 1960's Automotive Mechanics (Electrical), there is no way I can understand this Mumbo Jumbo.

Which Type are Hall Effect?

There are Two or more situations involved here, most talk about the Later HEI Systems on newer Cars with HEI compliant Tachs. with MSD Capasitive discharge ignition where you increase the Voltage from 4 Volts on the POWER Wire to the Tach, and then there is THIS totally different info, talking about filtering out "Noise" in the Ground RPM sensing Circuit.

http://www.marshallinstruments.com/products/9219.cfm

I am not sure that $85.00 MSD Box Bez recommended is what we need for a 60's Factory Tach. with the "Electronic Distributor", Maybe.

Sounds to me like the Wrong Parts or connections here could Smoke the Tach.

What I don't get is; what is the Difference between these Chicom Electronic Dist.'s and a Pertronix Module?
BOTH are "Electronic Ignition", but the Pertronix works just fine with a self contained Sun Tach connected to the Coil (-) Dist. Ground Wire and These do Not with the Factory Type with sending units. It must be the DIFFERENT Type Tach.?

[Lark Hunter]

Okay. Please pardon the potential ignorance here, but is there something bad enough wrong with the original distributors that prevents their continued use in these cars? Is it to avoid changing points every 10k, or are the original distributors just unworkable pieces of crap? It just seems like there's a lot of grief involved in getting a tachometer to play nicely with the new parts, so what is the rationale?

[StudeRich]

There are supposed to be advantages to these like; easily Adjustable Vacuum Advance, Programmable Mechanical Advance, it has 3 Sets of Springs and 3 Advance Stops to set it for Performance or Economy, of course no setting points, more stable Dwell, better Bearings.
But like a Pertronix conversion, if the Module Fails you better have a Spare or you will be walking!

But No, there is ABSOLUTELY NOTHING Wrong with the 1940's State of the Art Delco and Autolite/Prestolite Distributors except they are Old, the trick is properly Maintaining them.

I don't have a problem with a few NEWER things on my Old Cars, but in most cases I prefer not noticeable like the Pertronix System, but these are not terrible looking and almost out of sight, so just OK. I CAN paint it Black!

A BIG reason I wanted the Electronic Dist. in my Avanti are those difficult to adjust DUAL Points. They have to be individually Adjusted and dwell checked and then checked for Total Dwell before it is right, a total Pain without a Distributor Machine.
I know I should send it to my friend "Bud" a poster here, but that takes more time than I had, the Dist. was in Stock.

But all I want to do is get my Avanti Tach. working, so not to get into "Electronic" or not would be good, there are Dozens of Strings about the Pluses and Minuses of them.

[Lark Hunter]

Gotcha. Now I understand the appeal a bit more. I've only messed with one dual point distributor that I can remember.

[christophe]

Cam angle can be easily adjusted without a distributor machine and out of the car. The dizzy is to be held steady by its shaft. Then, you have to fabricate a thin hand that will be affixed to the body of the dist and a graduated sector that represents the angle you're aiming for. By hooking a test bulb or an ohmmeter on the points, you'll then be able to read the cam angle by rotating the body around the shaft. I has to use this on my Citroën DS 19 engine. Later, when I hooked the dwellmeter onto the engine, the cam angle was spot on at 90 degrees. I also like this method because it allows you to notice any unequal cam wear.
Nice day to all.

[JoeHall]

I had to use this when I put a hall effect triggered ignition in a Stude. MSD Ignition 8920 MSD Magnetic Pickup Tach Adapters | Summit Racing

Bez,
Pretty sure that's the same adapter I tried in one of the GTs I installed the HFI with electronic dizzy in. It worked, but the needle tended to lag, IIRC. I gave up and installed a modern tach to mate with the modern ignition. It looks close enough in the GT's dash for me. Of course I'll be 'judged' by purists at SDC Meets, but that's not a big deal for me. LOL

[DEEPNHOCK]

I had to use this when I put a hall effect triggered ignition in a Stude. MSD Ignition 8920 MSD Magnetic Pickup Tach Adapters | Summit Racing

That would make sense. I 'think' that their ad is conveying a 'crank trigger' style of magnetic pickup.
But, a Hall effect pickup would/should be the same, inside or outside the distributor body.

[Captain Billy]

Insight to the trigger differences

https://www.youtube.com/watch?v=PKl3WHv6w3M

[StudeRich]

Everything here so far has been about Modern cars 70's and newer, no '60's Cars with a Sending Unit AND a Tach. Head.