I have done it, using a flat6R and a 1.0 pod. I don't remember having trouble with the interior, and I also used a mag suspension in the rear. The spur gear was a 28T, and no problem with that either. On Ninco the car became ultra fast, but that has to do with the increased downforce that led to higher grip and managed to make use of the extra power. For non mag tracks, I think it wouldn't help so much....
I switched it back to SW eventually. I see no point in having a 312PB that laps faster than an Avant Slot R10 modern LMP racer.