The valve is meant to be used with a rubber fuel bulb. Open the door, give it a small squirt right into the cyl. then close the door. I think Sullivan still sells them but any small plastic bottle would do. Back pressure was not a concern back then. That is one of the first engines with a muffler. Before then we didn't run mufflers. If you want to quiet it down, put a nut and bolt through the hole in the front of the muffler. Get the centre of the tank up level with the needle valve if you can. Don't know what you mean by nozzle to pressure pipe. I have a bit later Fugi 15 in a combat job. Keeps up with the rest of them on 25% nitro. Name is Gord. Holler back if any more questions. Glad to help.