the biggest improvement is a result of the right ignition curve. And that can be done by someone who knows a little, has $20, and $10 worth of timing tape and advance weight springs.
exactly the same thing i was thinking. that ign curve does wonders.. the first one i ever did was an old accel dual point. heck had to be close to 290 years ago now... a friend showed me how to do it... got me 3 tenths in the quarter. i couldn't believe it.. but when you actually look at it and understand what just happened it becomes clear... it went from bringing total timing in at god knows where with the heavy springs that were in it to bringing it all in by about 2200 rpm... man did the car feel different....