"Baselining" my 225

Even with a bunch of idling and "flooring it" to test the kick down, the ignition tune up and carb swap has gained me 2MPG.
I bumped the timing up from 8* BTDC to 12* BTDC (it goes to about 24 total when revved). It seems a little perkier and goes down the road great, but at the cost of needing an extra revolution or so on hot starts. I'll run it like this for a tank or two and maybe try 10*.
It's definitely smooth and happy going down the road at the current settings. Runs cool, no pinging under load, etc.