[olddog]

I'll make another point. About the only things you can adjust, on a car engine, carb, by an external adjustment, is the accelerator pump, choke, idle speed, and idle jets. Anything to do with normal driving and WOT AFR is pretty much changing parts. In particular, jet sizes, power valves, and air bleeds. Tuning the AFR at WOT, which is where the hidden Hp is, requires draining fuel, disassembly, changing parts, and reassembly. If you are doing this on a chassis dyno, you are getting charged by the hour. So now you are playing with fuel on a hot engine in a car with a glass body encased in a flammable plastic. Or you are paying extra costs to allow the engine to cool.

If I am tuning an EFI car, I type some numbers into a look up table and press enter. I do not even have to turn the engine off.

Timing is the same way, I type in some numbers and press enter. You may be pulling a distributor and changing springs. You are locked into changing parts, while I am typing numbers and pressing enter. I have tremendous flexibility to shape my timing curve to any shape I want, you are limited to mechanical linear slopes. I can shape my AFR table to give any AFR I want at a multitude of operating conditions. You are limited to the physical parts available. I can try countless variations in minutes while it takes you a half hour to try one.

Which is easier to tune?