No more gravity turn?

@GoldenShadowGS
that sounds like a good method. maybe you can try the competition i launched few months ago, the rockets has an evaluation program that gave me hard time so i updated it in this capsule

My gravity turn is set to prograde the entire time after the initial tilt shortly after launch. I control my ascent entirely with throttle. I set throttle to a value to keep time to apo at a constant 55 seconds away until my Apoapsis reaches the desired altitude. At that point, its safe to stop engines and plan a circularization burn.

The efficiency depends on the initial tilt angle. Too much tilt will causes extra aero drag at best and not having the TWR raise the apo at worst, Not enough tilt will cause too much gravity drag. I set up a vizzy program that will control all of this and I can set different tilt angles to run trials and see which tilt gets into orbit with the least amount of dV used.

@GoldenShadowGS
You may never reach apoapsis if you depend only on the prograde lock, it will keep getting higher and further away, you have to override it at some point

@crowxe You will reach zero degrees when you reach apoapsis.

@Rizkyman that sounds efficient to have prograde all time for less project area drag. But the problem is if you followed prograde, the pitch will never drop to zero, it will halt at certain angle.

Gravity turn means you don't need to change your pitch, let the gravity do it by the craft following prograde line. That's the efficient way rather than pitching down the craft.
Lock Heading: Prograde

Basically speaking gravity, air density, TWR would be the main factors. Air density wouldn't be the first factor however. To calculate the efficiency you have to learn gravity loss.