Heres a little tech about 28-35 stock Ford wheels and some aftermarket ones
All these wheels had 5 on 5.5 bolt pattern and about the only other thing they had in common was that they all have a space for a flange inside the bolt pattern circle. This flange or two plane bolt patteren pad was only on mechanical brakes so when using 40-48 or any other brake setup a spacer should be used to give the 1928-35 wheel support on the inside of the bolt pattern, but many people dont and they ussually seem to be ok. But you should definately not use newer ford wheels on mechanical brakes.
Anyway, here a little about each stock wheel.


These are 21"x3" wheels with welded spokes. As you can see the top spokes are straight lace and the bottom spokes are single-cross. They have a rolled bead rim and are prone to cracking on the hub from one of the bottom spokes to the bottom or back of the hub.


30-31s are pretty much the same thing as 28-29s except for they are a 19"x3" wheel with a normal bead rim called knife edge. Same pattern for spokes, cracks in the same place and welded spokes.


These are 18"x3 1/4" wheels with welded spokes. The spokes are single cross on top and bottom. Hubcap hole size is 5 3/4, as is the rest of the wheels mentioned here forward. Unlike the two Model A wheels the lugnuts on these are covered by the hubcap.


These are 17"x3 1/4" rims that are pretty much the same as 32s.


Same as 32-34 wheels but they're 16"x4" These are by far the most plentiful because back in the war years, when a car needed new tires, a set of these wheels with new tires could be had for less than a set of 17" or 18" tires because of the price of rubber if you could find them. A good way to tell these apart from 17s and 18s without measuring is the valve stem hole. The 16" has a normal hole in the flat part of the rim, while 17" and 18" have the hole in a humped up area. (see pictures of the 17" and 18")


18" Ajustable Motor Wheel

17" Bent Spoke Motor Wheel

16" Bent Spoke Kelsey

16" Ajustable Spoke Kelsey

Some of these wheels have rivited spokes that have to bend right before they go through the rim so they can be rivited striaght, this is how they get their nickname "bent spoke kelseys". Where the spokes go through the hub they are not welded or rivited, but loose. Most of the 16" wheels are made by Kelsey-Hayes while most of the 17" and 18" wheels like this you'll see are made by Motor Wheel. You can tell if it's made by Motor Wheel or Kelsey-Hayes by looking at the dimples on the lower spokes. If the dimples go in, toward the bolt pattern, then its a kelsey, if the dimples go out, toward the rim, then its a Motor Wheel. Also the Kelseys have 40 spokes and the 16" Motor Wheel had 36. The 17" and 18" Motor Wheel has 32. The 16 inch Kelsey bent spoke wheels came in 2 different widths 4 inch is the most common and a 4 1/2 wide that had a flat area around the valve stem hole. Kelsey and Motor Wheel also built ajustable spoke wheels. The spokes on an ajustable wheel are held together by little nuts called nipples. The nipples go through the rim and screw onto each spoke. Kelsey made ajustable spoke wheels in 17", 16" and 15", they also had 40 spokes. On the 17" and 16" the top spokes crossed twice and bottoms crossed once. On the 15" wheel the topspokes only crossed once and the bottoms didn't cross at all. Motor Wheel made an ajustable spokes wheels in 18", 17" and 16". The spokes on Motor Wheel ajustables were swedged, which means they are bigger where they come through the hub than where they connect to the nipple.
Kelsey and motor wheel also made adjustable spoke wheels in 16 X 4 with lock rings for easier mounting and dismounting. The rims where made by firestone Lock ring wheels are like trucks had in the 1930s thru about the 1970s

Taken from a post by "Wheelkid" that originally appeared on the HAMB