Must have a look at that, Enfields had 4 sp foot change for quite a while prewar.
Big range of models though, maybe my interests have been concentrated.
Yes, it was reputed that the military asked Enfields for more power from the (sidevalve) WD/C, since even for convoy work it wasn't too speedy.
The WD/CO (ohv) was the result, but only being a 350 it and the M20 and 16h were about the same.
btw, I've mown the grass/weeds with a mower with an Enfield G (ohv 350), and it only needed to be idled,
talk about chomping through the grass. Where my interest for Enfields came from ?