- Joined
- Oct 13, 2004
- Messages
- 1,781
Actually, the on-off valve was MOUNTED between the remote NV and the carb. The only fuel tubing connected to the valve went directly to a third line into the fuel tank. The controline people that flew the Navy Carrier event used this type of fuel system to fly fast laps and some very SLOW laps, also.In the early 70's, Leland Morton and I had a 2 stage fuel valve in a B Proto ship that was centrifugaly operated. It had a primary jet for takeoff and a secondary that opened when the centrifugal force overcame the spring.(When it came on the pipe after takeoff). We flew that setup sucessfully for about a year and half. It worked well at times, but didn't have consistancy. The KISS principal is the winner in most cases. In my experience, you also can't give up the velocity in the venturi, or make the case so large that it suffers for lack of base compression. Bigger is not always better. It still has to pump.Back in the late 1980's ( 1980's technology, anyone? ) I played around with a .21 Mono and pressurizing the fuel tank with crankcase pressure from the engine. From what I can remember now, crankcase pressure is somewhere around 2 or 3 times more than typical pressure from a tuned pipe. Only drawback to using crankcase pressure was that you had to incorporate an on-off valve between the remote needle valve and the carburetor. This valve was operated with the throttle servo. When the engine was operating at full throttle the valve was shut, allowing pressure to build up in the tank. When you started closing the throttle, the valve would open which would allow pressure to bleed off from the tank. If all of this extra pressure stayed in the tank when you throttled back the engine would flood and cut off. Initial runs showed that the system did indeed work, but I didn't really see enough gains in performance to warrent the extra work in putting this in the boat. Just something else to go wrong, you know? Another idea from my controline flying days..............
Dick Tyndall
Bob keeps bringing up names from the past that sound familar. I believe that the FAI Speed fliers used something similar.............weren't they called "speed switches" or something like that?
Dick