from the looks of it, and untill its closer to being done it will be hard to tell, but it looks like the seats are like 16" further back than stock and depending on the fuel cell placement they are likely going for a much broader polar moment than what the stock configuration will allow. this gives them the ability to have a car that will sit flatter in the huge whoops more like a trophy truck rather than getting bobbed all around.
which by the looks of it, and how well the last car Jimco built worked, i bet this one is going to be absolutely insanely fast. i am sure it has a lot more going into it rather than just your standard "slap a cage on it and go racing" build.