As mentioned in earlier posts by other members, the Morgan 3W engine is not a Harley but a S&S proprietary design, sharing no parts with Harley engines. Even the V angle, at 56 1/4 degrees, is different from the Harley traditional 45 degrees. It does have in common an uneven firing order for that characteristic 'Harley' sound (and vibration). Being 2liters, it is not too small for the 3W, there are many cars heavier with much smaller engines and with far less torque.

13year old article about the X-Wedge: [url=https://www.jpcycles.com/countersteer/moto-101/s-s-reveals-innovative-x-wedge-engine][/url]https://www.jpcycles.com/countersteer/moto-101/s-s-reveals-innovative-x-wedge-engine

Now if S&S with produce the X-Wedge with a master/slave connecting rod design, or an offset crank pin, for a 360 degree firing order (both piston reach TDC at the same time with alternating firing, like a parallel twin Triumph) with a gear driven balance shaft, then the Centra [likely] wouldn't be needed.