Originally Posted by funola

Shooting down is better, but shooting horizontal is OK. I was talking about bending a set of injector lines and have all injectors connected to the IP while mounted to the engine. If the lines are long enough and there is sufficient clearance to point the injectors down, do that by all means. If not, then horizontal is fine. At 2000+ psi, the spray pattern is not going to be affected by much whether the injector is horizontal or vertical. Make sure you put a clear jug on each injector and don't shoot any fuel into your skin.

ps what is a "gauge with a top pressure needle"?