i was wondering why a stall leads to lower numbers on the dyno? yank has told me that their stalls are more efficient than stock. if that was the case wouldn't they increase horsepower throughout the powerband?

 

If the converter is more efficient than stock, it will make more power on a dyno. Some (many?) higher stall converters are not more efficient than stock (they slip more) meaning they would show a little less hp on a dyno, but still make your car faster in a 1/4 mile. Some of Yank's converters are pretty efficient.

 

that and i heard higher gears do the same thing?

 

more drive train loss in a4 than m6 pretty big difference. get a built tranny, wont have the problem as bad as a stock tranny