Check your spark plugs and fuel filter.
I think you might have a bad head gasket. Just a guess.
Stalling rough. Like stalling while on a hill. That made mine skip.
Most of the time rough running and stalling is due to vacuum leaks. There is more of a load on the engine when it is in gear, so that lends itself to stalling out. When I look for vacuum leaks, I have the engine idling (maybe you need a friend to keep it from stalling) and then spray carburetor cleaner around the various hoses & gaskets that could be leaking. Any increase in the idle speed would be an indicator that you have a leak in that area.
your idle settings might be to low. check on your engine near your carb for a small screw that is all by itself
A bad cdi, will cause no spark if its completely bad, but if its going bad can cause misfires, random stalling and rough running, like alot of backfiring and stuff.
300zx twin turbo lots of black smoke and running rough
Poor fuel miliage, rough idle, no start, poor acceleration, stalling.
Rough idle, low injector pressure Sputtering stalling. lack of power
sound like bad rings It doesn't sound like bad rings, if it was burning oil the smoke would be blue. Black smoke sounds like it's running too rich, that would explain the running rough, stalling and lack of power, it's getting more fuel than it can burn.
Clean out the IAC (idle air control) or replace it. Check the TPS (throttle position sensor) also. Clean out hte intake also.
Trail shoes are shoes for running in rough terrain. They are bulky and heavy I do not recommend running with them in places were there is not rough terrain.