dart 340 I.D.

71 Darts in the US didn't have a 340 available unless it was a Demon. It could have had an engine transplant.

A Canadian swinger 340 could be a possibility, highly unlikely.

That's interesting! I didn't know that. I'm gonna say that it is a plain 318. I might still go back and get it for the 8 3/4 axle and V8 parts. I can sell the axle to pay for the car and still end up with V8 conversion stuff.