Hi Mf ,Gadge and Paul
that cowl could be seen from space (with a spy satellite anyway).
Why is it so big?
The Wolf Garden Cowl would work as a noise suppressor it's the 4 stroke version of the 2 stroke Victa Vortex.
that motor has an interesting feature combo; apart from the dipstick, the alloy muffler a la Kirby/Tecumseh 2-stroke is very unusual.
The two top images are the 4 stroke and the 3rd image is a 2 stroke motor (different mowers).
Cheers
Max.