I have a overdrive too, I 've almost run a gallon through it and it runs great. My carb settings are 2 turns open on the HSP and no adjustment to the LSP. I've had problems with glow plugs, I seem too be going though alot of them, already went through 4. I use the OS #3's. Other than that i've havent had any problems with the velocity 17 engine, except just newbie problems. My only problem I had was when I went through a ditch full of water, about tire high and the water splashed up under the hood and socked the air filter(im assuming thats what happened). And then it shut off. It works now though, luckly that didnt kill it. When my enigine dies ill probably invest in a fantom or picco .15 engine.