Hi friends

I need to ask you a question

currently my car (01 Miata 5 speed box changes)
has MP62 supercharger + stock Pulley motor + SC Crank Pulley Nose 62.5mm
and load 10 psi with a peak of 11.3 psi

I want to buy SC Nose Pulley 60mm or 58mm to improve power
(I hope to improve 2 psi, which would you recommend?)

other question is:
"As my box 5 speed resists" which I recommend to keep it safe.
I have currently 949racing clutch Ceramic 4 puck - Sprung Hub kit with + Flywheel.


thank you very much for your help