It's not the power that is the issue. The 020 TD sets up an occilation in the 22k to 23k range that becomes a brick wall holding the rpm down. Even mounting it on a piece of pergo on the test stand and pre-drilling the screws I ran into this. I could take the same motor and bolt it in and pick up 2-3k or more. Could be why cox propped it with the 4.5 X 2 prop and keep the rpms down.