Re: What makes for a ‘racing’ lower unit?

[legendre]

It seems that tractor LUs fell out of favor long ago, particularly in general service engines. So what was the theoretical advantage of the tractor design?

The obvious difference is that in a tractor, the prop is first through the medium, and the tractor LU structure tails the prop – whereas with a standard pusher, the LU structure leads the prop.

So was the leading-prop arrangement believed to be superior in some ways? Was it ever so, and if yes, why isn’t it still used?