Non Model A & B Distributors
- Thread starter LeroyM
- Start date
Jonnyenglish
Member
Anyone got any more info on this? Which model, years etc will work on the A?
Joey Anchors
Junior Member
Sorry to bring back an old thread, but I was doing some research on dual points and found the modern Mallory 2301105.
When using one of these do you keep the stock coil and is the distributor a 6v setup?
My plan is to run one with a Scalded Dog single intake/97, Lion III, Y-dual headers and when/if the A's engine needs a rebuild I'll be upgrading the cam/crank/bearings at that time.
When using one of these do you keep the stock coil and is the distributor a 6v setup?
My plan is to run one with a Scalded Dog single intake/97, Lion III, Y-dual headers and when/if the A's engine needs a rebuild I'll be upgrading the cam/crank/bearings at that time.
Tom Wesenberg
Well-known member
Dual points give the coil more dwell for more coil saturation. This might help on a high speed V8, but certainly isn't needed on a Model A. Purdy mentioned several times about the hot spark of the FLAME THROWER coil he used, if you need more spark. I've had good service from my stock ignition and slant pole coil.
A note on "hot coils": A Super Duper Flame-Throwin' Bug Zappin' coil only produces enough voltage to fire the spark plug no matter what it's rated at! When the points open and the coil's primary field collapses, voltage rises in the secondary windings only until there is sufficient energy to jump the plug gap. Thus, if 5,000 volts is enough to produce a spark, 5,000 volts is all the coil will produce. Higher compression pressure and/or a larger plug gap requires more voltage so the plug may not fire until the secondary voltage rises to maybe 10,000 volts. The advantage of a Mega Trick Zap-Ya'-Good coil is the reserve capacity. If the plug gap or rotor gap wears larger than specs, the coil can still fire the plug. It will also handle higher compression than a stock coil.
On the down side, a hot coil draws more amps than a stocker. which amperage of course flows through he points. Therefore points don't last as long. Also, if the plug gap and/or rotor gap gets too large, you have a higher voltage flying around inside the cap which can lead to stray sparks jumping to ground, jumping to the wrong plug, or eating through the rotor.
With stricter emissions laws in the '70's manufacturers had to go to a leaner fuel mixture. It takes a larger plug gap to reliably fire a lean mixture, which requires a higher voltage coil, which requires more current, which burns points quicker. Thus we now have solid state, or electronic, ignition. We also have heavier and better insulated plug wires to contain that high voltage.
On the down side, a hot coil draws more amps than a stocker. which amperage of course flows through he points. Therefore points don't last as long. Also, if the plug gap and/or rotor gap gets too large, you have a higher voltage flying around inside the cap which can lead to stray sparks jumping to ground, jumping to the wrong plug, or eating through the rotor.
With stricter emissions laws in the '70's manufacturers had to go to a leaner fuel mixture. It takes a larger plug gap to reliably fire a lean mixture, which requires a higher voltage coil, which requires more current, which burns points quicker. Thus we now have solid state, or electronic, ignition. We also have heavier and better insulated plug wires to contain that high voltage.
hardtimes
Well-known member
Hey 40 Deluxe,
Well stated. In addition, there are a few 'things' that can be easily done to help keep the spark going to where it is supposed to and not elsewhere.
Along the lines, and in keeping with the magnetos mentioned, as distributors of spark, here's a side drive four cyl example from the shed.
Anyone have the other half of the 'drive' that connects to the cam cover ?
Just connect it to the right front of you engine
Well stated. In addition, there are a few 'things' that can be easily done to help keep the spark going to where it is supposed to and not elsewhere.
Along the lines, and in keeping with the magnetos mentioned, as distributors of spark, here's a side drive four cyl example from the shed.
Anyone have the other half of the 'drive' that connects to the cam cover ?
Just connect it to the right front of you engine
Attachments
Last edited: