I have a sanwa MT4s transmitter.
Should i set the throttle epa at 100% or 150% them recalibrate.
Can I set it at 100 recalbrate then adjust epa to get more punch.

the radio will not add more punch that way

calibrating at 150 will increase the level of precision by 150/100 = 50%

That means when you adjust the EPA, it won't be nearly as drastic as setting it at 100

I would only do this if you're struggling to find a brake setting between 2 points at 100, which I personally have never felt the need to increase precision myself.