Car appreciation... the aesthetics, the engineering, etc

Piffle. The LS1 is a classy lump and parts for it (even in Aus I guess) are dirt cheap and very readily available. It's incredibly flexible and tunable.

Those Jag V12s run hotter than a bradford vindaloo and cost a packet to rebuild.

Pretty sure none of the modern V8s kicked out more than 400hp...though they are a nice engine.

Dirt cheap. Precisely. Fitting one to a Jaguar turns a thoroughbred into a mongrel.

The Jaguar V8s kick out a lot more than 400bhp in their supercharged variants.
http://www.jaguar.com/gb/en/r/r_specifications
The 5 litre supercharged v8 gives 510/625 except in the XKR-S where it gives 550/680.
Unsupercharged is 385 horses which is still more than a crate LS1