You fellas using the OS 160 twin, what brand and size prop are you using? I'm using a pro zinger 18x6 prop and can't get a good loop. It falls out of it or if I try to do a large loop it runs out of steam unless I apply down elevator first and even then its iffy. I was thinking maybe a carbon fiber 18x8 but wanted to see what others are doing. The engine is turning 8200 rpms with the pro zinger.