Does anybody have experience with running a remote needle valve and pressure system in free flight? I have a Royal .25 engine that is set up for combat with a remote needle valve and the airplane I have in mind for it uses a crankcase pressure system. So with the needle valve about an inch away from the venturi, I am wondering if it might lean out on launch.
I had a remote needle on my OS MAX III 29X, in a 650 sq in Dixielander. There was no problem with running or surges but I eventually modified it to a regular intake-mounted K&B needle because it was such a pain to fill the bladder. I generally have a shut-off in the pressure line and just fill through that and close the shut-off before re-connecting the line. With the remote needle the shut-off would have had to be upstream of the needle in order for the needle not to restrict the filling process – and then the shut-off would be difficult to operate during starting. I ended up filling through the flood-off line and using the timer shut-off. It worked fine but it was just such a nuisance to have a different arrangement on that aeroplane compared with all my others that I changed it.