[yuhaoyang]

a dboys spring in my custom G&P mechbox output enough eK to go through the side-bottom of a pop-can. And the dboys nozzle doesn't seal. it makes air gush out the bottom. actually, neither does the piston head. yeah... get a modify cylinder set is all I can recommend really... also the DBoys spring is really really short and very strong, which is how it achieves such high fps. Most springs are about an inch longer.