I have a LA .46 on a profile Cardinal that I have been flying for several years. I usually run a 11-5 Pro Zinger prop. I have found that at 650 feet above sea level here in north Texas that about 3.5 ozs. is more than enough fuel to do the pattern. I use 10% or 5% nitro and 29% castor, what we call Super Stunt fuel. I use a clunk tank set up on a two line system with pressure from the muffler. It always burns all the fuel. I have thought about getting one of the free flight timers to mount on the ship so the fuel would be cut off somewhere around 7 1/4 minutes or so. Then when I go fly in the higher elevations I am not concerned about over runs. I flew in Albuquerque last August and the first flight ran over by 6 seconds. I did receive a fair judge and lost landing points. It is strange that one flight will run short of fuel and by adding just a half ounce of fuel the engine will run another 2 minutes. Really when you stop and analyze a flight there are a lot of factors that have to work in your favor in order to score well. And that is just the mechanical and atmospheric part not to mention the subjective judging that we all do and get. Here in Dist. 8, we the Dallas Model Aircraft Association, give out an award in Oct. for the Dist. 8 Championship. It is given to anyone making the most scoring in the district contests. Dale Gleason has won it the past several years now. It takes lots of money and time to travel to the out of state contests, the equipment has to work well, you have to fly it well, and place. Not an easy feat by any means. I have seen men take on this challenge in past years and win the coveted trophy only to of accomplished that and we never see them again. Trophy hounds! If this is you then you have my blessings. Personally I had rather compete and let you take the trophy home with you and to of enjoyed my day of flying. Anyway go fly the engine and experiment with different fuel levels. I'll bet that 6 ozs. of fuel will get you a 10 minute run.