I get the impression that most people continue to take timing of up to 20lbs or whatever they are running.

I read a long time ago (in reputable articles) that after ~12lbs you should flatten off your timing curve. This is what I've always done... I get my timing down to 14* (or whatever) at 12lbs and then flatten off from there.

Am I crazy or are others doing this too?

 

I always thought you get on a dyno and tune the timing from that. Just guessing a X amount of timing is not the right way. Dyno will tell you the best timing to run.

 

overlay you torque curve on your dyno charts...add 2-3 degrees and see if you pick up significant torque. tune by MBT basically.

As the rpms increase you'll want to advance the timing because the actual elapsed time (in us) it takes for flame to propogate and create cylinder pressure doesnt change, but the angular velocity increases.(rpm) You'll need to give the flame kernal the same amount of time to generate the max cylinder pressure when the crankshaft is perpendicular to the force applied (T=RxF)(obviously its not as static as that...but you get the idea)

When I tuned my timing I took almost no timing out until 6psi and then took more timing out as I followed my VE table/ compressor map. I ran about 4 degrees retarded from what I thought was right...then went to the dyno and tested it.