Why switch box marked 4/8 1969?

[timguy]

I wish to sell a vintage Mercury switch box from my stock and don't quite understand the marking. It is part number 332-2986A-22. What does the 8 mean? So apparently it will not fit the six cylinder in lines? This is a brand new item I have had on my shelf for many many years. Thanks, Tim

 

[racerone]

Likely works on a V-8 Sterndrive.

 

[timguy]

Thanks, Racer. Mercury is quite confusing sometimes to me. I prefer OMC, also interchangeablity.

 

[faztbullet]

The only Mercruisers I ever saw with this was 427ci's in a houseboat with TR drives and a old military river patrol boat that had outdrives that could swivel from 90° to 45°.

 

[timguy]

So that was a Ford? Crazy! In automotive applications, electronic ignition came out in the mid 70's.

 

[racerone]

Ignitions on outboards was ahead of automotive in the late 60's to a degree.

 

[Quicksilver]

It means 4 cyl 2 stroke or 8 cyl inboard this was for the tach signal.

 

[timguy]

Agreed, Racer. So in this case this was only to provide a tachometer signal but did not control the spark electronically? I don't think this subject has much merit today but I have never seen it covered. It's so easy to just hook your tachometer to the distributor side of the spark coil on a points ignition. Why the box?

 

[Quicksilver]

The way the ignition worked was engineered for Mercury's tach which used higher voltages and rise times. When you bought a motor you could get the tach to go with it which was a better one than a car tach (waterproof, shock proof etc.).
anyone that buys that swichbox can use an alternator driven tach.

 

[faztbullet]

So that was a Ford? Crazy! In automotive applications, electronic ignition came out in the mid 70's.

No it was a Chevy

 

[timguy]

Okay, interesting. So what year is the box? One guy on eBay has it listed as a 1969, so its really for 1975/76?