Tuning 362 flat top valve question

[baranjhn]

I have a 362 that I like to shoot at the 12 ft. lb. level. With 6 pumps I come in at 11 flat with 13.43 gr JSB pellets. With 7 pumps, I get a little over 12 ft. lbs. My question is: If I install a flat top valve and piston, could I get 12 ft. lbs. with even less pumps? Or do these just add room for more air and I'd still need to pump 6 or 7 times. My goal is less pumps for longer shooting sessions at the 12 ft. lb level.

 

[airgunner53]

A flat top piston ads more power by means of maintaining the same pressure per stroke. The pump cup will experience more flex and will compress resulting with increased head space as the pressure in the valve increases resulting in more head space between the pump cup and the valve cone. Key would be to remove head space. A modder here introduced the mod of reducing head space by installing a pin in the inlet valve. This alone would increase pressure and reduce the number of pumps needed even with the stock pump cup.