273 vs 318

I am really thinking that with my dream of 12's being limited by the rule book, that I will just build the 273 with the mild cam,redo the heads for unleaded gas,add a 4barrel and appropriate headers. The car won't be a screamer,but it will look and sound good. A buddy of mine also has an A-body 8 3/4" laying around that He said is "workable". Anything I do is going to make the car at least a little better in the performance end.