"Back in the day," before the demise of Modified Eliminator, there was a variety of modified cars that were the staple of NHRA's showcase of racing rolling stock; Gas Coupes, Street Roadsters and Modifed Sports Cars. These cars were, ostensibly, all cars that had been (usuallly) re-powered with engines that were heavily-modified and gave their host vehicles performance capabilities well-beyond their original designs and usual-displayed abilities.
This made them appealing and exciting to watch; Thr idea that a Model A coupe (or, roadster) for example, could achieve the kind of performance that was the norm in, say, A Gas Supercharged, was so foreign to the oriiginal visual concept that most folks expected of a square-bodied Model A, that its surreal appearance, going 140 mph at the finish line, made spectators do a double-take, and that scenario was repeated, over and over, as multitudes of really fast cars (that looked as though, they should never have had the kind of performance that was commonplace in the Modifed Eliminator ranks, caused fans to stare, awe-struck, at the cognizant-dissonance on the racetrack.
Fast-forward to 2016. The cars that populated the class Pro Mod's early days, emulated yhat scenario I just described. As I remember it, the currently-popular trend toward late-model (aerodynamic) bodies was not too much in evidence, with a large variety of "fifties" (and, earlier) bodies populating the class.
Plese correct me if I am wrong, but it seems to me that, reading the class rules, these cars have a lot in common with the Gassers and Street Roadsters of the early days; Both were/are mandated a 10-percent engine setback, both use and used 4-wheel, sprung, suspension, both require(d) "door-car" bidies, and, both have/had heavily modified engines with a conventional transmission setup.
These are, more than anything else, the "Gas Coupes" of the new millennium.
The only difference is, they make a LOT more power!
I think that if NHRA would offer some kind of performance-based incentive to these racers to encourage the utilzatuin of "early" body shells, it might increase their visual-appeal and the already-popular class might become even MORE popular...
Pro Stock is not looking good right now, and the possibility exists that someday, Pro Mod could be upgraded to a "Pro category" status.... but, I am not holding my breath...