The LA .40 is not known for its power and in some circles, a flat out dud but they do run well. Have somebody show you how to tune it in. Some people run their engines on a bench before installing. I feel that is a waste of time and just break mine in on the plane. Get it dialed in as best you can and once you get your high end leaned out, richen it up a couple hundred rpms. Somebody around should be able to show you how to tip the plane up to check the enging also.

You can also double check what youe done by running the engine at an idle and pinch off the fuel line by the carb until it dies. If the rpms increase before the engine quits, your low end needle is to rich. If the rpms just go down and the engine quits, low end is too lean