@ #37: How exactly do you expect the efi to increase the power output in any meaningful way? The only real world advantages to efi is that it saves a meaningless amount of fuel and is more precise to keep tha stoichiometric ratio under all conditions which is a prerequisite for the cataclist to do a somewhat meaninful job.
Well, you could start with the 650 & UCE section where folks are using the tuners to increase both drivability & power. EFI allows accurate metering under a highly variable set of real world conditions, like altitude/air density, air temperature, etc. Viczena has lectured long & hard on this. Many members here have dyno time verifying it. Personally my 24mm carb on my 2002 ES350 works adequately for my needs, but 16-18 HP isn't hard to come by.
"Bee not the first by whom the new is tried, nor the last to cast the olds aside" B. Franklin