Hi Andy that is better known as a self propelled power plus.It doesn't have a power torque engine.It is a full crank 160cc,it should have a different head from and normal full crank engine.Just to give it more kick.Where as in the other picture you added is my 1977 VC-160 Auto Drive Mark III.You one should have a G4 carby,(could have been replaced with a LM carby by now)Not a lot of difference.Yours should be around the 1978-1980.Post up the engine number(Carby side lower crankcase)I may may be able to tell you year from that.I would have thought your Victa code would have been WU189A8 or WV173A8 depending on which model you have.Any more questions please ask.

Here for a good time,not a long time.