Honestly, another 2.5 class would be ok, but it would really have to be a big difference from the 2.6 and workstock to be a good varient class. In order to do that you would have to limit air and fuel both, and even go as far as limiting electronics on CR vehicles, and pump size on 12v's.
Electronics: I would outlaw any stand alone AND EFI live all together. Any power electronics used must be in form of a hand held programmer and/or a box that plugs inline with the factory wiring harnesses.
Turbo: Small Frame off the shelf turbo's only. i.e: S300, HT2B, HX 40 or 50, GT40 (i think, maybe GT42) and any other similar turbo series. Limit every aspect of the turbo aswell so that no custom job could slip in and take the show. Air to Air intercoolers only, no water or bottles of any kind.
Injection pumps: Limit to one CP3 on CR engines, p-pump engines are allowed up to a 12mm. I know alot of fuel can still be had out of a 12mm pump. If you think it would be necessary, you could even limit things such as DV's and plate sizes maybe, maybe not.
I know it would be hard to enforce the turbo internal limits and p-pump limits with just a basic visual inspection. But honestly this would have to be a protest thing. If someone protest, then what ever is protested on the truck in question would have to be taken apart and measured to prove that the truck is legal. If that person will not want to tare his truck apart, then they will be stripped of thier winnings for that pull.
This would be the only way you could really regulate that class, but it would still be a money class.
The only problem with doing this is, I believe the workstock class and a 2.5 class such as this would be way too close to being the same on the track.
What would actually be a better idea I think would be to allow the 12v and 24v VP trucks, and also the Ford 7.3L to run a 2.45 turbo, still being a small frame charger and with other internal limits to make it basically an off the shelf turbo. I know alot of you are thinking "well why not let the CR vehicles use a 2.45 aswell", but honestly, we all know a stock turbo 12v or VP truck probably will not stand a chance against a CR vehicle in most situation. Even with an HE351 turbo, I still don't see either of them giving a CR a good run for thier money at least.
Just throwing this out there. THis is the idea I had in my head if some one wanted to make this class run with a sanctioning body. I just don't see how you could have much difference between the 3 classes with adding the 2.5 back. It would be closer to a workstock level IMHO. But if used in a county brush pull, or added as a non sanction class at a sanctioned event (sanctioned members could not pull the 2.5). This would allow people with a basic off the shelf 2.5 charger and a box or 2 to get thier feet wet to see if they like it with out getting discouraged because they got dead last in the 2.6 class and couldn't pull workstock.
Like i said, just throwing this out there. Don't hate on me too bad about it........