argue, argue . . . that what every bugger seem do on here!
well let look at it this way the air in to the solenoid is destined for the ram . . . how else does the bolt move. . . if the solenoid gets starved of air then the bolt ain't moving anywhere quick. . .so hence the VFF mod to separate air specifically for the solenoid. . .to stop drop off (i guess). . . .the LPR well it does what it says on the tin, lowers (controls) the pressure of air to the solenoid. . .so you can raise the valve pressure which will provide higher air flow. . .and as Walker boy say allows the dwell to be lowered.
Now to me purely from a design point of view (I ain't an impy owner!) using both the VFF and LPR together would be benefical. . . because firstly the LPR will give controlable pressure to the solenoid and the VFF will provide a storage of air to make sure it doesn't get starved!
But if the impy had a decently design high flow valve and separate air chamber for the LPR none of this would be required!!
oh yeah walker it's the hammer that hits the valve . . . not the ram
But on the original topic. . . .have a go of both a see what you like!!
So everyone chill and be good kiddies and play nicely!