Well I'm not one to tell anyone what to do. I don't know what the owner wants, and I don't know what kind of budget you are working with,... but you gotta keep that supercharger/side draft weber on there!! It looks so mean! I understand wanting to step up the CCs a bit from an EA63, but perhaps you could fit the supercharger set up to an EA81, maybe re-jet the weber?
Do you think there is anything interesting in the case? Modified cam maybe? High compression pistons?
The owner told me to get it to run and drive for him, do what I think is best. If it was mine I would have done an EJ22, but he wanted to stay with a carb and something that looks more original. Other than that it's up to me what to do.
The EA63 is done for. It must have been detonating bad with the supercharger. I found a melted spark plug. I tore it down and one head is melted in the chamber, the top of one piston is on the way out. It's got a couple of valves starting to burn and one cylinder is pitted from sitting. It's just got stock pistons, it does have an aftermarket cam, there is an old school sticker on the car for it too.
The EA81 on the other hand is in nice shape. No wear in the cylinders, everything looks good. I'm putting it back together with all fresh factory gaskets and putting a weber on it. That's what's going in the car.
I know people like the supercharger, but it's small and unreliable, it obviously killed the EA63. It was made in the 50's for 1200cc VW's and it's too small for an EA63 no less an EA81. They don't make any real boost anyway. The guy who owns the car isn't really into subies, he's a vw guy. I just want the car to run well for him and be reliable.