Can make it simple...but labor intensive (you have to test.cronograph a lot).
1. Open the transfer port restriction screw up.
2. Fill to 2800psi and shoot 25-30 shots.
3. For now, IGNORE the energy per shot.
4. If the shots start slow and increase in speed by quite a bit over those 15-20 shots, then you need to increase the striker spring tension....adjust the spring tension in 1 turn IN and try again with a new 2800fpsi fill.
5. If the shots start fast and decline over those first shots, then you need to LESSEN striker spring tension a bit ...adjust the strker spring tension OUT 1 turn and try again.
6. Ideal is for the velocity at 2800psi to start off about 3% slower than whatever the max speed turns out to be...and decline to about 3% uder that max speed.
7. Fill to 2800 psi and now look to the transfer port restriction screw. If you want max-reasonable power for the best shot count, then just screw the transfer port screw in a little bit at a time until you notice an unexpected deacline in speed/energy. Then back it out 1/4 turn...that's about as much energy for the fill pressure as you can have with a decent shot count.
8. If you have an eye on even less energy (lets say you fixed on 12 foot pounds), then just keep tuning the transfer port restriction screw in until you get there (starting a little low at 2800...peaking at somthing like 2400...and falling down under 3% of max at about 210-19000psi).
Havbe two of the critters....the abocve pretty well works for botu with good efficiency/log shot counts....just nto the mega energy some folks crave.