Would there be any interest in a programmable electronic points replacer?

dumb person

dumb person

Well-known member
I know lots of you (including myself) like the simplicity of the original system. So i'd design something that was about 5 minutes work to swap back to how the model A should be.


While tinkering with electronic ignition i found i can make a very simple system for the model A with programmable advance. You could dial back the advance for high compression heads, or add a small potentiometer to the carb' for maximum fuel economy. A simple D.I.Y. device you too can make at home.
It could be as simple as a tiny box on the firewall under one of the coil fastener clamps.


Or if you have more resources you could make something that replaces the points cam (although i'd rather leave the points cam and make a points plate without points)
My current set up only works well on 9 or more volts.

So before i order parts online & hope they come (if i have spare time, hopefully i will, considering...)
 
So I guess 9 volts or more means a car already converted to 12 v is a prime candidate. Given how fussy my phaeton is about ignition timing, I'd be interested in more info like $.
 
Advance mapping for model a ford engines is simple,1 degree advance per 100 rpm fits the bill.Raising compression does not change that basic parameter,in fact,advancing above that for high compression can cause damage.
 
Adding a potentiometer (throttle position sensor) to a carburetor will be of little value without extensive mapping of a specific engine build because it would not be independent of fuel metering/lambda/lean/rich.

What is really needed is a MAP sensor input so you could have a selection of vacuum advance/retard profiles over selectable RPM advance tables. (A generic MAP sensor is about $25) That would give you excellent economy cruise and quickly compensate for variable engine load while accelerating, going uphill, etc.

Missing from all the points replacement systems and modules for older Kettering ignition vehicles is a time-out system to prevent current drain if the engine is stopped with the dizzy cam sensor in the old 'points closed' position. Not only does this prevent the coil from cooking due to 100% dwell saturation time, it keeps your output switching MOSFET from getting smoking hot on its heat sink and possibly failing. Easy to do- output gate clamped via a simple timer until the cam sensor delivers pulses less than a few seconds apart.
 
Last edited:
MikeK said:
Adding a potentiometer (throttle position sensor) to a carburetor will be of little value without extensive mapping of a specific engine build because it would not be independent of fuel metering/lambda/lean/rich.

What is really needed is a MAP sensor input so you could have a selection of vacuum advance/retard profiles over selectable RPM advance tables. (A generic MAP sensor is about $25) That would give you excellent economy cruise and quickly compensate for variable engine load while accelerating, going uphill, etc.

Missing from all the points replacement systems and modules for older Kettering ignition vehicles is a time-out system to prevent current drain if the engine is stopped with the dizzy cam sensor in the old 'points closed' position. Not only does this prevent the coil from cooking due to 100% dwell saturation time, it keeps your output switching MOSFET from getting smoking hot on its heat sink and possibly failing. Easy to do- output gate clamped via a simple timer until the cam sensor delivers pulses less than a few seconds apart.
Click to expand...


Can I get an app for that?

David Serrano
 
The problem with getting away from standard is that when you break down on a tour, your buddies can’t help you. You better have a spare you can put on, or be able to fix it yourself. 8
 
I would be interested. I talked to a company at the SEMA show last year that is making programmable distributors for 60's V8's. He said he could probably make one for a Model A, but it would be in a V8 housing. Not ideal. The MAP sensor input would be a must. Running a Zipper now, but would be great to be able to have the retard feature under load.
 
Flathead said:
Or......you could use mechanical points. :)
Click to expand...
Well, yes. Points are resistant to EMP, nuclear fallout, and polarity. But i've been there done that.

I did get it working on 6 volts with some trickery
But then the microcomputer died from voltage spikes.

I'll defeat this puzzle somehow...
 
Jacksonlll said:
The problem with getting away from standard is that when you break down on a tour, your buddies can’t help you. You better have a spare you can put on, or be able to fix it yourself. 8
Click to expand...
With the 12 volt prototype i made, you wouldn't need a spare. You'd just bypass it & use the points as per factory. It was using the points as a reference to cam' position.
 
Along with MikeK's suggestions, you should add a knock sensor for optimum spark advance at all times.

Back in the day I put a points eliminator setup on my '74 Mustang V6. IR sensor across the cam lobes (with adapter) switched a transistor to drive the coil. No more burned points or worn rubbing block. Worked great until I sold it in '81.

Yeah, those 6 volts are a PIA, especially the negative ones.
 
Last edited:
lsr490 said:
Has anyone looked at this http://www.kirkengines.com/index.php#1 ?
I have two on hand and looking to install one here shortly.
Click to expand...

The product description states that the coil should be 3+ ohms: “The use of . . . coils with resistance values lower than 3.0 ohms will cause the module to fail.”

It looks like you’re ok if you have converted to a 12 volt system but those of us with original 6 volt systems may not be able to use it.

Unless the the electricity gurus on the Ford Barn can suggest a workaround, it may be worthwhile to bite the bullet and convert to a 12 volt system. Too bad I just bought a new 6 volt battery.

I’m interested to hear what your experience is.

David Serrano
 
lsr490 said:
Has anyone looked at this http://www.kirkengines.com/index.php#1 ?
I have two on hand and looking to install one here shortly.
Click to expand...

The product description states that the coil should be 3+ ohms: “The use of . . . coils with resistance values lower than 3.0 ohms will cause the module to fail.”

You’re ok if you have converted to a 12 volt system but those of us with original 6 volt systems may not be able to use it.

Unless the the electricity gurus on the Ford Barn can suggest a workaround, it may be worthwhile to bite the bullet and convert to a 12 volt system. Too bad I just bought a new 6 volt battery.

I’m interested to hear what your experience is.

David Serrano
 
lsr490 said:
Has anyone looked at this http://www.kirkengines.com/index.php#1 ?
I have two on hand and looking to install one here shortly.
Click to expand...
The original post of this thread was for a system to add ignition advance. This device does not do that.

Among the multitude of devices designed to replace capacitive resonance(the condenser) with a single sharp field collapse in the coil ('transistor switching'), this one is the worst I have seen.

Here is what is inside:
picture.php
Since this is not an electronics forum I won't go in excessive detail, but if you get a dozen 30 minute trips in a Model A with this in the distributor it will be a miracle. It was designed (poorly!) for a lawn mower.

Even the manufacturer's install instructions tell you very bad things about the design:
"Operation with a poor or non-existing ground can instantly destroy this device when power is applied!" (You need a dedicated ground to the battery in a Model A)

" Do not mount in the breaker points box as overheating and subsequent failure will occur!" (breaker points box on a lawn mower is equivalent to the distributor on a Model A, a HOT place!)

Good luck with it!
 
rally 1 said:
Check out MSD #8680, adjustable timing control
Click to expand...
That device provides MANUAL control just like the advance lever on an A. Additionally, it only has a 15 degree range. The O.P. ('dumb person') wants to automate that function.
 
The model T programming wasn't playing nice on a single cylinder, and for some reason decided microseconds wasn't going to work anymore.

So i made do with milliseconds.
So close to making a simple module that bolts across the 2 coil posts...
It was even working on both 6 and 12 volts.


https://youtu.be/9YYLSqjWV9s


But then the pro-micro died from me trying to make it use shared ground/power with the coil & battery.
Hmm.... At least the coding side is getting closer.
 
With all due respect I ask what will be the significant advantage over what Henry used in his cars. Regular points are simple to install, maintain and very inexpensive. Why try to reinvent the wheel?
 
You must log in or register to reply here.
Back
Top