340 or 318 turbo

I have a 1972 Dodge Dart 4 door as a parts car with a 318 already running low compression. I picked up a 1973 340 low compression I have a single turbo. And always wanted to build a 33318 but the 340 fell into my lap [ame="http://www.youtube.com/watch?v=jaGKq0s7CWY&feature=youtube_gdata_player"]Turbo V8 - Franks VJ Chrysler Valiant - YouTube[/ame]. Had made me want to build a 318. Car that I want to build up is a 1967 Dodge Dart I have a good size Garrett turbo an 8.8 rearend.