My first guess would be a slipping clutch. How many miles on the clutch?So, every once and awhile after some brisk driving I get the smell of either brakes or clutch...well the other day I also noticed smoke!
It seemed like the smoke was coming from UNDER the car. It was also kind of windy that day so I couldn't pin point it.
Is the smell a normal thing? I'm pretty sure it still has the stock pads on it.
Could the clutch not be releasing all the way?
You can test for slippage by accelerating (and/or popping the clutch) at a very low speed ( 10-15 mph) while in a higher gear (4th or 5th). If the engine revs freely the clutch is slipping. If the clutch is not slipping the engine should bog or at least struggle slowing against the higher gear.