...Ya could pull ALLA that crap and cure about 100% of your vacuum secondary headaches...forever!
Talk about a snappy throttle response!
But, on a more serious side, assuming the mechanical dimensions are close, then it is things like cam timing, spark timing, fuel/air ratio, plug condition, etc, etc. etc. that makes up the tune; aside from passenger perceptions, It could be one of those things. How do they compare on the dyno (is a better question)?
P.