I was under the impression it was the other way round. The AXX engines were less "restricted" by emission controls.
But yes it true the AXX is the last of the lean burn. Basically putting less fuel into the engine when it doesn't need it. Cruising at legal motorway speeds for example.
The the bean counters also had an input. Early GTI were sold with a huge reduced margin, some even say at a loss!!!
So wouldn't be surprised if cheaper alternate components were used too in the later 06MY.
Later cars lost 10 speaker stereo, Blue Tint Windows, Naked Roof (unless SatNav fitted) rear window seals (3DR), S3 lower arms (Before they were fitted to the Audi S3) plus some little touches like the alu trim to the ash tray.
Else the engines are physically pretty much identical. All producing a "claimed" 200PS ~ 197BHP.
Hopefully someone more knowelgeable can correct or shed more light on this.
