14 sec ... that's pretty fast. Most stock Corvettes with 5.7 liter or even 7-liter ran in the 14s ... only a very few are 13-sec cars from the factory.

With the light weight of the Datsun 1200, its not too difficult to make them a 14-second car. I'd go with the A15 and build it up just like you'd build an A14 (the extra 7% displacement will help).