Yes, pressure is controlled with that allen socket.
Tell us what injectors you have fitted, and if you can check - tell us what size nozzles are fitted in your injectors, and we can guestimate what pressure the reducer should be set at.
The reducer will come preset at 0.9 bar, it can be adjusted to a max of about 1.5 / 1.5 bar by unscrewing the allen socket. Most likely (can confirm this when you answer the above), best results will be had with pressure set at the reducers full 1.4 / 1.5 bar pressure. Better to err on the side of too much pressure for your application / reducer combination. When you have reached the highest pressure setting, you will hear a click when unscrewing the allen socket (this is the screw coming off the threads inside the reducer), further unscrewing will not increase pressure further. To ensure maximum pressure, unscrew until you hear the click then unscrew until the point is reached just before you hear another click...
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