Ignition Upgrade


(Photo: Welch)

The IH V220 has a 549 petrol V8.  Rumor has it best mileage may be around 4mpg…

At one time back in the late ’50s, this may have been the largest truck engine of it’s type.


For all that swept volume, it doesn’t have much go.

The compression is good and even, the fuel supply appears adequate, yet once the truck gets rolling, it feels weak and for lack of a better word, ‘lumpy’.

I suspected something in the ignition, as breaker point gap changes made a difference.

I’m not much of a fan of points ignition.  Electronic  sparkers deliver hotter, more consistent  spark, and they either work, or not.

It seems that recently, the quality of both points and condensers has dropped, to the extent that I will re-use old parts when possible.


Rather than use a Pertronix conversion, I opted to adapt the breakerless ignition from a late ’70s Dodge truck.  In part because the system is simple, relatively cheap, and readily available, and also as I have a NIB spare controller for my ’88 W100 plow truck.  Another consideration is the relative expense of the Pertronix, both initially, and should it fail.

I have heard some rumors about sensitivity during jump starts. (This may not be true, but…)

This is the mock up of the ‘breaker plate’.  This disc will rotate under vacuum advance.  The black Sharpie marks everything that will be removed.

The lower plate is original, and the black plastic is the previous breaker mount.  It slides in a semicircular slot in the lower plate.

Adding clearance for the trigger wheel.  This 4-jaw is junk.  The jaws are loose and the work is not parallel to the face.  It was free, and this is the first time I made use of it. The sloppy work holding isn’t critical for this part anyway.

Clearing out the lower plate. I need to preserve the two small cutouts above and to the left of the boring tool.  These notches seat the friction spring for the black plastic advance plate.

I am holding my good 4 jaw in the 3 jaw.  This is Ok for light cuts at slow speeds, but at some point I need to get an actual back plate…

Removing all that doesn’t resemble a horse…

Test fit.

If I do this again, I will have the actual distributor on the bench to better determine the layout.  As was, the truck was up the road a few miles…So I guessed.

I had hoped to be able to install the rotor shaft, and then the plate/pickup assembly.  It didn’t work out that way though, and the whole thing is just a bit less serviceable.

Spinning the South Bend.

With the easy part done, I am now past the point of no return.  With the lobes turned from the rotor shaft, there is nowhere to go but full steam ahead.  The cam is case hardened, but workable with carbide bits.

Trigger wheel inverted to locate the first spring pin hole.

These holes are not 180 apart.  The inner dull metal is soft, while the outer shiny metal is hardened.

Turning the shaft to accept the trigger wheel in it’s correct orientation.  I made a mistake, as the collar should be thicker.  The wheel is tight enough on the shaft, so along with the spring pins, it won’t matter if it isn’t seated fully.

More or less.

All over but for the shouting.

And it works.  The truck runs quite a bit better, no doubt in part to adjusting the timing closer to where it should have been.

Smells better too.