1. Since you have an LSN setting that is drastically different, you should be very careful with the head shim thickness. I personally would not run that engine with less than a .4mm thick head shim, but it's your engine. If you do go with a shim less than .4 check for signs of detonation - frequently.
2. you can get more punch by changing clutch adjustments and gearing.
3. What tuned exhaust pipe and header are you running?
"Yellow Jacket" Mugen MTX-6, Picco Torque
TeamNITRO RC Club, Lynwood, Illinois