Total Advance timing 3TC weber DCOE RPM question

[clemsyn]

Trying to get the best timing on vehicle. I set the initial timing at 15 degrees (by adjusting my dizzy) at 1000 rpm, at 3000 rpm my total advance timing is 24 degrees (using timing light with a dial). A few questions...

1. Do I need to block the brake booster connection before I do this testing.
2. Do I need to go higher RPM for total advance timing (like 4000 rpm).

Thanks.