Dirty, read the below brief history of Cragar wheels that I lifted from the Roadsters.com website. There is no mention of a 4 inch wheel ever being manufactured. Cragar doesn't list one one their website either. That doesn't mean that there wasn't one, it just means that I couldn't find any mention of one. Unless you are purchasing wheels new, be careful what the seller is calling a 4 inch wheel. Depending upon where the measurement is being made, the wheel could appear to be a 4" or a 4.5 ".
As a side note, you can fit even the narrowest of street tires on a 4.5 inch wheel without any issues. Visually, there wont be any discernable difference between a 4" and a 4.5" wheel.
"The design of the Cragar S/S began in 1962, with marketing starting in 1964. Its styling was influenced to some extent by American Racing Equipment's highly-successful five-spoked Torq-Thrust wheel.
The S/S was one of the first production wheels to use a cast aluminum center with a rolled steel rim (both of which were chrome-plated), the way some 1957 Cadillac wheels were made. The S/S was also the first die-cast aluminum wheel. The wheel was designed with ribs and extra material added near the hub. The result was a wheel that offered a load-carrying capacity that was unmatched in the aftermarket wheel industry. Its classic styling made it a huge success with drag racers, hot rodders and custom car builders.
Cragar S/S wheels were made in 15 by 4 1/2, 6, 7, 8 1/2, and 10-inch sizes, and I've also seen early versions of them in 16 by 10.
In addition to the standard 4 1/2, 4 3/4, and 5-inch bolt patterns, S/S wheels were originally also available in the then-popular early Ford 5 1/2-inch bolt pattern.
The original Cragar S/S is still being produced, along with a newer version, designed by the late Larry Shinoda, which is offered in larger diameters."