Another D/Dart 275/273 question???

Your probably making peak horsepower around 6500rpms and peak torque around 4500rpms I imagine you want to shift high enough that next gear starts in around your torque peak, I'm thinking of building my 273 but almost everyone says its a waste of time how did your turn out would you recommend?

I have built my 273 from 65, its a commando. Well I have put a camshaft as the 340s, big valves 2.02/1.60. OpenAir intake with an Edelbrook 600 on the top. HP exhaust with 2.1/2" dual pipe with X-pipe.
Here is the teoretical result.

As soon the summer comes I will see if it is correct :glasses7: