How to upgrade an R2?

[Avanti83]

If you are interested in the car staying close to original, start a conversation with Jack Vines Packard V8 above about having your engine or a replacement rebuilt.

Ir you don't care about original, get a recent Chevy LS with your choice of trans and put it in. Cheap performance and reliability.

There are engine mounts to adapt the LS to the older SBC mounts used in the later Avanti's and programming is available to upgrade the original LS computer to be used in another vehicle.