Excuse the Bill Clinton reference in the title, but I had a quick thought on the DeltaWing proposal. No, stay with me. Hey, no, put down the gun. Really, no! This won't be that bad! Whew, close one!
Perhaps the most often heard comment on the DeltaWing is, "I wonder if they can apply some of the principles from the DeltaWing to some of the other chassis designs." Basically, can you rework the Swift to be based on the open-source model, or could the Dallara be changed to embrace the fuel-flow regulation model of controlling speeds?
Some of these could maybe work - the fuel regulation seems fairly straightforward - but others are so fundamentally different that I just can't see a chassis design company like Swift suddenly deciding to open-source their work.
The single biggest advantage I see to the DeltaWing, though, is that it solves the problem of how to let multiple engine manufacturers run very different engine configurations. I said the fuel-flow regulation model might be applicable to other chassis, but it goes well beyond that. By no longer requiring the engine to be a stressed member of the chassis (unlike pretty much every top-rung formula car of the last three plus decades), it is far cheaper to supply engines for the car. In fact, the engine cost is one of the biggest areas of cost savings under the DeltaWing plan! Without that fundamental difference, the DeltaWing would not be such a radically cheaper chassis. It also (in concert with the proposed fuel-regulation system) allows teams to install basically any internal combustion engine that will fit in the engine bay. Inline-4, V6, V8, straight-6, flat-4. If it fits, it flies.
So why don't the other designers go this route? I'm not an engineer, but looking at the other designs, they all look like the engine is a pretty major part of the rear end. I would be shocked if the Dallara, Swift, Lola, and BAT designs don't use the engine as a stressed member. That not only means that the engines are much more expensive to produce, but that they must conform to a much tighter set of dimensions, which basically puts you back in a position of mandating a particular layout, and soliciting bids. Sure, maybe you end up with Honda, Lotus, and Volkswagen all supplying a turbo 4 engine, and that's certainly a ton more competition than the IRL has now, but it's way less than you could have in the DeltaWing, and it's way more expensive.
As I've said numerous times when discussing the DeltaWing, I am not convinced that it's the right direction, but to consider it without giving plenty of attention to the engine portion of the puzzle is to miss a major advantage of the plan.