Engine Transplant Question

[Boyscout]

IMHO you would be better of with a good 998. If you up the CR to as high ad you can get it on the small bore head. All the economy mods as per David Vizard, you will get close to your targer consumption. Performance will be better than the diesel as well. The cost of the conversion will probably be more than petrol costs over the lifetime of the vehicle.

Modern common rail diesels have complicated control systems and is beyond the scope of most. Earlier diesels are heavy and have relatively low power output for displacement.

Possible candidates are Opel Corsa diesel. Imported Toyota 2C which will have to be mated to Mini gearbox or other suitable box.