Upgrade Points Distributor To Fire With A TFI Module

[bmbm40]

Converted my wife's daily driver to points-controlled electronic ignition using a Motorcraft ignition module off a '93 F150. Credit for this swap goes to gofastforless.com. I emailed the man who wrote the site to verify a couple of specifics, and he responded, which I appreciate.

The goal of the project was to keep from having to clean/change points, which are hard to get to on this vehicle. But the after-swap test drive showed an (unexpected) noticeable improvement in idle quality, (50 rpm increase in idle speed), throttle response and acceleration clearly better. Felt like the first drive after a timing advance, after a season of running with soggy timing. I wager an economy improvement is a sure bet.

This is not a Ford vehicle, but the information may be valuable to those with old-vintage engines, where ignition upgrade options are limited, or you prefer to keep the factory points distributor in service. For this vehicle there are no upgrade options, except PerTronix, (requiring breaker plate mods to fit it). A proven factory engineered and built ignition over a compact aftermarket unit provides more peace of mind IMO.

The TFI module controls the dwell, the ignition system operates on full battery voltage, and the points only see milliamps of current. A vast improvement over the ballast resistor, full amperage passing across the points, and regular tuning to keep the points clean and properly gapped. The gap is unimportant, as long as they make-break contact, the module handles the rest. The coil fires on points opening (breaking the contact), the same as stock, therefore no ignition timing change is necessary. (Using a Chrysler ignition box on points, the coil fires when points close (make contact), requiring a resetting of base timing.)

Post-swap timing and dwell check showed no change in ignition timing. Dwell was 30* at idle, 31* at speed, and never varied. (Inline 6)
Relative to swapping a distributor this is a far easier conversion, and leaves the factory timing curve intact.

Use a GRAY colored module. Any black module won't work. The early type with the 3 pins on top will work, the newer remote-mounted modules are better, already bedded in a heat-sink. Use the factory harness plug if available.

**EDIT- Follow-up report, 9/30/2024: This system is still working perfectly 14 months after install. Untouched since install. Engine starts instantly and runs perfectly. **

PIN 1 and PIN 4: IGNITION SWITCH POWER (full battery voltage) AND COIL POSITIVE (+)
PIN 2: POINTS WIRE. This is the wire from distributor to coil negative (-) when stock. Remove from coil (-) and attach here.
PIN3: not used
PIN5: COIL NEGATIVE (-)
PIN6: GROUND
View attachment 17369

If the module is well grounded, pin #6 GROUND can be omitted. I used the pin, running the wire to the voltage regulator/engine block ground lug on the generator. Take the time and get everything clean. A good ground is key to correct function and longevity.
View attachment 17371

Take the time to solder the connections, and use a quality glue-infused shrink-tube.
View attachment 17375

BEFORE
View attachment 17372

AFTER
View attachment 17377

View attachment 23571

View attachment 17390

Appreciate the update. This is a great ignition mod.

 

[DON]

Good stuff Frank.

 

[chad]

If it were a wagon I’d “know where U live”.

 

[alwill923]

I just installed a DUI dizzy. Probably more expensive but a lot easier.

 

[chad]

Frank sez wrong diz this app.
the ‘module’ (or whatever the thing was called then) looks smaller than the ford of the era.

“...Using a Chrysler ignition box on points..."
one of our most active, informational (a cam engineer?) guys here usta swear by these.
(bon; bombe something like that) I think Ilearned that co was probably 1st in ele. ignition
creation (in US?) from him.

“...Credit for this swap goes to gofastforless.com..."
THAT guy has given me more than any 1 (even Mustang Steve) in my weakest area. Sure
makes it worthwhile to surf (rather than get more household chores done). aahahahaa

I see your mod was for points inacessability. Where’s the dizzy on this FH? I dont C in pics.

 

[Frank]

I see your mod was for points inacessability. Where’s the dizzy on this FH? I dont C in pics.

Yes that's right. The distributor comes out of the block at around a 30* angle, almost sits flat. And the points mount on the bottom of the plate. There's no way to see the points at all, never mind the awkward body position leaning over the fender trying to fine tune them. The engine has an external oil pump, so the straight angle from the pump to the cam to the distributor is almost horizonal. I reclocked the dist so the points are on top, but it's still a hard reach and hard to see.

Oil pump


Distributor

 

[Frank]

“...Using a Chrysler ignition box on points..."
one of our most active, informational (a cam engineer?) guys here usta swear by these.
(bon; bombe something like that) I think Ilearned that co was probably 1st in ele. ignition
creation (in US?) from him.

The Mopar box is good. The snag is that it fires the coil when the points close, the opposite of other systems. Thus there will be a rotor-to-cap alignment problem, since the distributor has to be moved to correct the significant timing difference of when the coil fires. The rotor will not be aligned with the cap tower when the points are closing. So more modifications to re-phase the distributor are needed for it to be right.
Blairsville Ed ran a Mopar box on a points big6 successfully, but he had to remove and relocate the slot in the rotor about 20* to get it to fire right.

 

[chad]

thnx for the 2nd pic. It DUZ show da tough location. Glad U came up w/a fix.
I’m thinkin it’d B insane to try’n efi the lill flattie. Nother way round (but wrong direction).

Still fening for your Y/M but wagon model. My American 400 vert (’61/3) model had such
a smooth motor folks would laugh @ the kid (1970) @ the light thinkin it had stalled out.

 

[Adriatic Machine]

Great article but I don’t see any suggestion of part numbers for this gray box module. I guess I could ask the auto zone guy for a gray box module just to watch his head explode but that won’t do much for my car.

I just went back to points on my 59’ 223 after doing the 300 distributor upgrade. I’d like to keep the points and run a module. My buddy suggested I use the MSD box but I really don’t know enough about this stuff.

 

[Frank]

Great article but I don’t see any suggestion of part numbers for this gray box module. I guess I could ask the auto zone guy for a gray box module just to watch his head explode but that won’t do much for my car.

I just went back to points on my 59’ 223 after doing the 300 distributor upgrade. I’d like to keep the points and run a module. My buddy suggested I use the MSD box but I really don’t know enough about this stuff.

The MSD box has a greater potential to arc over in the small distributor caps on the old points distributors. And they're sensitive to RF frequency from the points/ plug wires, the module is not. For me, it's also too much fire power for a stock daily driver, MSD is just not necessary- aside from the drawbacks listed above.
The module can make as hot a spark as any factory system, depending on the coil. A can coil will work, the stock points coil would probably work, IDK for sure. On the Rambler I've got an old Mallory can coil that specifies "for electronic ignition", it was already on the car with points-only when I got the car. On the truck with points/TFI I'm using a TFI coil, factory on the EFI era engines.

I had the module already, on the engine in this article. Used, off a '93 F150. For the '79 truck I bought one for the '93 f150 application. I think RockAuto had the best price. I also went with Motorcraft which was more expensive than the off brands. #DY1075

1993 FORD F-150 4.9L L6 Ignition Control Module (ICM) | Shop Now at RockAuto

Ignition Parts and More for Your 1993 FORD F-150 at Reliably Low Prices. Fast Online Catalog. DIY-Easy. Your Choice of Quality. Full Manufacturer Warranty.

www.rockauto.com

To make wiring simple and dependable I got the module harness from here, good quality working good on the truck.

Standard Ignition 6 Terminal Multi-Purpose Connector S-544 | O'Reilly

Find the right Standard Ignition 6 Terminal Multi-Purpose Connector for your 1962 American Motors American at O'Reilly Auto Parts. Place your order online and p

www.oreillyauto.com

If you want to replace your points coil and stay with a can coil, get one for the DS2 era. A '79 F150 listing will work.
If you want to go TFI coil, this will be the best match for the components and probably the hottest spark. Get one listed for a '93 F150. I got the TFI coil now on the '79 from RockAuto also, for a '93 model.

As far as heat dissipation for the module, the big factory heat sink shown in this thread seems to be overkill. I have the module mounted on the inner fender on the truck. Flat surface, sanded paint off and used heat transfer grease. The module never gets more than slightly warm to the touch.

 

[Adriatic Machine]

Excellent! Thanks again. A friend of mine has been trying to convince me to take this route, although with the MSD box.

I was running Pertronix in my Loadomatic system and recently upgraded to the 300 style distributor which came equipped with NOS points. I like the idea of using an OEM design module. I gotta say I’m impressed that people figure these things out. Good work!

 

[Frank]

The module

Excellent! Thanks again. A friend of mine has been trying to convince me to take this route, although with the MSD box.

I was running Pertronix in my Loadomatic system and recently upgraded to the 300 style distributor which came equipped with NOS points. I like the idea of using an OEM design module. I gotta say I’m impressed that people figure these things out. Good work!

Thanks. I'm impressed too, 'cause I sure didn't figure it out. It really does work well. I'm 100% happy with both vehicles, they start instantly, run flawlessly. It's true there is some benefit to the MSD box with it's multiple sparks. I prefer as simple as possible, keeping the stock timing curve and not worrying about magnetic or RF noise messing it up. Points are considered a digital signal because they are on/off. that's why the TFI module works, the factory Hall Effect distributor is on/off. All other electronic ignitions are a magnetic sine wave including Pertronix.
Let us know what you come up with!

 

[sixtseventwo4d]

I was running Pertronix in my Loadomatic system and recently upgraded to the 300 style distributor which came equipped with NOS points. I like the idea of using an OEM design module. I gotta say I’m impressed that people figure these things out. Good work!

Have you checked to see if the Pertronix will transfer into the other distributor?

 

[Adriatic Machine]

Have you checked to see if the Pertronix will transfer into the other distributor?

Yes, I did check and it will not fit. The Loadomatic 223 advance plate is center pivot so the Pertronix module has a small curve that kind of wraps around the magnetic pick up sleeve. The later distributor pivots from one side and has a flat magnetic surface.

 

[Adriatic Machine]

The module

Thanks. I'm impressed too, 'cause I sure didn't figure it out. It really does work well. I'm 100% happy with both vehicles, they start instantly, run flawlessly. It's true there is some benefit to the MSD box with it's multiple sparks. I prefer as simple as possible, keeping the stock timing curve and not worrying about magnetic or RF noise messing it up. Points are considered a digital signal because they are on/off. that's why the TFI module works, the factory Hall Effect distributor is on/off. All other electronic ignitions are a magnetic sine wave including Pertronix.
Let us know what you come up with!

Sure thing! I won’t have time to mess with it until next month the earliest. When I do get around to it I’ll post some pics and share my results. Thank you for sharing the links / part numbers
Jimmy V

 

[chad]

“...MSD is just not necessary - aside from the drawbacks listed above...."
plus expense.
“can coil” known (@ suppliers as ‘oli filled’) as there were those w/o oil looked same

RELIABILITY: 1967 Classic oil-filled coil The oil-filled ignition coil is one of the oldest types of ignition coil and belongs to the category of distributor ignition coils. It can generate 25 – 30 kV and will supply several spark plugs via a mechanical distributor. Vintage and older cars often have classic can-type coils filled with oil or asphalt, which tend to run out. 1991 Distributor block ignition coil This ignition coil is also in the distributor ignition coil class. It was developed to guarantee increased reliability and output compared with the can-type ignition coil. 1998 Complete ignition coil systems This design is used by some vehicle manufacturers. It combines several single-spark and dual-spark ignition coils into one unit, also known as a ≫rail≪. It is mounted on several spark plugs simultaneously. One benefit: such systems can be equipped with an ion flow gauge, which can be used to monitor the combustion quality in the engine control unit.

DOWNSIZING​

1999 Block ignition coils With the increase in engine performance, ignition coils have had to produce higher ignition voltages, while simultaneously withstanding higher temperatures. Block ignition coils were developed to meet these demands. This type of coil can generate up to 36 kV and is available with single-spark and dual-spark technology. In the single-spark design, each ignition cable provides one cylinder with high voltage. In the dual-spark variation, the high-voltage pulse is delivered to two spark plugs simultaneously. One of these spark plugs produces a spark that sets combustion in motion. The second only produces a support spark. The exception: engines with two spark plugs per cylinder. 2013 Pencil coils Modern downsizing engines are more compact, but boast turbochargers, and sometimes even compressors. Due to the higher pressures and fast mixture movements in the combustion zone, high ignition voltages of up to 40 kV are needed, and the risk of disruptive discharge or interference increases. Therefore, this type of ignition coil is installed directly onto the spark plug, where it also generates the high-voltage pulse, decreasing the risk of power loss or voltage flashover. In addition, this construction type takes up very little space in the engine bay.

Here’s another for interest.
I use the DSII Ford ignition system as I’m post SCV/LOM (’64 and ’68). I was given the brain/controll box for that (post ’77 DSII)
that comes w/the prefered ‘blue strain relief module’). I will replace it with a later GM 4 Pin HEI as it’s smaller, more easily sourceable,
cheeper (last 2 big points for me). The hei makes it hybred so purests may say “No”. My net is acting up or I’d post the schematics (very
simple). Y can get it at go fast for less dot com. A very good site to learn what you say is a bit ofa puzzle 4 U right now.
H T(his all) H

 

[Frank]

“...MSD is just not necessary - aside from the drawbacks listed above...."
plus expense.
“can coil” known (@ suppliers as ‘oli filled’) as there were those w/o oil looked same

RELIABILITY: 1967 Classic oil-filled coil The oil-filled ignition coil is one of the oldest types of ignition coil and belongs to the category of distributor ignition coils. It can generate 25 – 30 kV and will supply several spark plugs via a mechanical distributor. Vintage and older cars often have classic can-type coils filled with oil or asphalt, which tend to run out. 1991 Distributor block ignition coil This ignition coil is also in the distributor ignition coil class. It was developed to guarantee increased reliability and output compared with the can-type ignition coil. 1998 Complete ignition coil systems This design is used by some vehicle manufacturers. It combines several single-spark and dual-spark ignition coils into one unit, also known as a ≫rail≪. It is mounted on several spark plugs simultaneously. One benefit: such systems can be equipped with an ion flow gauge, which can be used to monitor the combustion quality in the engine control unit.

DOWNSIZING​

1999 Block ignition coils With the increase in engine performance, ignition coils have had to produce higher ignition voltages, while simultaneously withstanding higher temperatures. Block ignition coils were developed to meet these demands. This type of coil can generate up to 36 kV and is available with single-spark and dual-spark technology. In the single-spark design, each ignition cable provides one cylinder with high voltage. In the dual-spark variation, the high-voltage pulse is delivered to two spark plugs simultaneously. One of these spark plugs produces a spark that sets combustion in motion. The second only produces a support spark. The exception: engines with two spark plugs per cylinder. 2013 Pencil coils Modern downsizing engines are more compact, but boast turbochargers, and sometimes even compressors. Due to the higher pressures and fast mixture movements in the combustion zone, high ignition voltages of up to 40 kV are needed, and the risk of disruptive discharge or interference increases. Therefore, this type of ignition coil is installed directly onto the spark plug, where it also generates the high-voltage pulse, decreasing the risk of power loss or voltage flashover. In addition, this construction type takes up very little space in the engine bay.

Here’s another for interest.
I use the DSII Ford ignition system as I’m post SCV/LOM (’64 and ’68). I was given the brain/controll box for that (post ’77 DSII)
that comes w/the prefered ‘blue strain relief module’). I will replace it with a later GM 4 Pin HEI as it’s smaller, more easily sourceable,
cheeper (last 2 big points for me). The hei makes it hybred so purests may say “No”. My net is acting up or I’d post the schematics (very
simple). Y can get it at go fast for less dot com. A very good site to learn what you say is a bit ofa puzzle 4 U right now.
H T(his all) H

Hey chad! Thanks for the info. The HEI module works great on DS2. That's what's on my other truck, the '90 with the original 300. I like the HEI module better- as you say, cheaper, way more compact and can keep a spare in the glovebox,

 

[chad]

some of the racers use it

 

[pmuller9]

And they're sensitive to RF frequency from the points/ plug wires, the module is not.

Can you explain what you meant by the MSD box being sensitive to RF frequency from the points/ plug wires?
I'm not familiar with this problem.

 

[wsa111]

You need spiral wound spark plug wire to eliminate interference.