The "Average Joe" way of boosting power:
1-Increasing octane value. Commercial octane boosters, or moth balls in the gas tank.Tried and proven.
2-More efficient air intake.take off the air filter cover for short & fast bursts
3-Optimise fuel-air mixture, and try to add another combustible gas to the mix. (i personally used a propane tank,leading to the carb of my '86 Tredia) The diffrence is huge.Also,you can try to use hydrogen(harder to come by),acetilene,oxygen (a bit of an oddball really,but should work),Alcohol vapours,butane and lpg might work too.They're all pretty easy to get. Pretty much DIY. Try not to blow yourself up.Use a gas regulator!
4- reduce weight and eliminate friction. Should be obvious.
5-Questionable...Set your distributor to give the spark a bit later,when the compression is at its highest point.