Say you lock the distributor at 33 degrees. Set your timing at idle, about 1000 rpm. Run it forever there, until you learn about slew rate and that 33 degrees at 7400 is more like 27 degrees. There’s an easy 15-20hp loss maybe more. If you lock it out, set the timing at your MAX rpm. When you do that, at idle it’ll show more than than 33 degrees, And through peak torque you’ll be on the verge of rattling unless you have a lot of converter and a light car.