I think the Torana in the picture might be a LC or LJ six cylinder? Did Peter Sloman run one of these prior to the LH SLR5000?
Regarding Blondie's Standard Ten, the engine was the 2.1 litre 4 cylinder Standard Vanguard engine that was also used in the Ferguson TE20 tractor. With a supercharger, power output was considerably more than the original 948cc 4 cylinder as factory fitted to the Ten. Looking at the photo, I think Blondie is also using a beam front axle 'sprintcar style'. Trevor Gray used to do the same with his early Vauxhall sedan.
Speedway Saloon rules of the day (and until quite recently) required engines to be of the same number of cylinders and from the same manufacturer as the body, although a fairly wide interpretation of 'manufacturer' was applied by competitors and allowed by the then Speedway Control Board.
For example General Motors was considered as one manufacturer and that's why Chev engines were seen in V8 bodies by the likes of Pontiac, Oldsmobile and Holden to which Chev V8's were never fitted. But more than a few competitors pushed the barrier including Mike Weymss' Simca Vedette which ran a Ford 302W. How a French car that had a French built 2.3 litre V8, based on, but with few parts interchangable with the old Ford V8 60 motor, and whose manufacturer 'family' wise was actually part of the Chrysler group, could legally under the then rules run a Ford small block certainly puzzled a few. Perhaps the later change of body make to the Sunbeam Tiger, which was actually produced with a Ford 260W was a follow on from this?