hay, why it's AWD?
30 fps on nForce 8600GT and ~20 with lags on Radeon HD3400. It's all because of polygons. I can easily speed up it to 50 by converting to perfect geoms
About recoil - you can use this tech
The problem is you need to place all textures inside you scene or no one see it because if you set texture in run-time you need to have it on disk. So result: epic fail.
You must store explosion texture somewhere in scene (like on invisible box). Since it's created during runtime and we don't have it there is only white boxes instead.
It's not bouncy, it's like it should be. No suspension, remember. Add it and everything will be fine. Plus you can adjust springs to any desired values.
Well, ok, but the problem is your vehicle is 2 by 9 meters so it's about twice bigger than usual tank.
So in result it's only 30 km/h equivalent, which isn't so fast.