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Hi,  This is my first post on your forum. I thought I would ask the experts across the pond for some help.
I have bought a 1971 Aston Martin DBS V8 for restoration which does not have its standard Aston 5.3 Litre V8 engine. In place of it is what I think is a Chrysler V8 as it has Mopar labels on everything. I have been on the imperialclub site which gives you the position of the ID numbers and serial numbers but the only number I can find is stamped on the block near where it joins the Torqueflite  autobox which was standard on these cars. It read A421C with 00227 below it. The carb is a 4 barrel dated 97 on the casting. I have some pictures of the engine but don't know if you can post them here. Can anyone help me ID the engine? It sounds great when you start it and give it some gas ! It runs at 35-45 psi oil pressure at about 2000rpm so it appears in good condition.

Cheers from UK.