Mk1 Mk2 commonality

The engines and transmissions have a number of differences but can be interchanged. However the Mk1 engines don't have a take off for the mechanical fuel pump as they use an electric one situated at the rear. There were changes to the 2nd gear ratio and the final drive ratios but not sure if the latter is true for Oz cars as I seem to recall they retained the lower gearing.

Early Mk1 cars had different drive shafts (not the plunging type). As there were changes in Oz to the engine mountings on Mk11 cars they may have a different engine front plate but all that can be converted if it is the case. Mk1 engines had smaller inlet valves and lower compression but that shouldn't be an issue - you can fit a Mk11 head to a Mk1 engine but not the other way round. I think Mk11 Oz cars ran with lower compression than the UK because of lower quality fuel. If you fit a MK1 engine it would be advisable to to keep it's distributor, carb and inlet manifold to keep the timing and fuelling right. The MK11 car starters were pre-engaged (UK) so there would be a bit of fiddling with the wiring but nothing too onerous.

I can't comment on the auto transmission but would be surprised if there are differences between Mk1 /11, but stand to be surprised!

No doubt I've forgotten a few things and others will add to or correct the list.

David