Well folks I am going to give some input here as I used to own the better car that used the 2.8L; Ford Capri. Anyway, dlofc, as is said the 2.8L is a very strong motor although the '74 motors were problematic as it was the first year of the 2.8L. As ohgami mentioned: rod through block; I heard that alot back then. If you are willing to start with a slightly better 2.8L get one from a '84 to '86 Bronco II, Ranger, or Aerostar. Bigger cam bearings (another weak point of the car 2.8L), and I am pretty sure the crank was strengthened. As for performance you could get ahold of Norm Murdock at
www.teambltz.com or join the caprilist through Yahoo-groups. Norm more than likely has what you need for your motor, although it is spendy. By joining the list you might be able to get someone that might part with an Offy 360 4bbl intake. As for Norm he has been racing the Ford Capri since the '70's so his input would be very good. Norm only does emails no phone calls.
For what it's worth this is my first post. Also, in the past I had a '74 M II 2+2 - 2.3L 4sp, a '76 M II 2+2 - 2.3L 4sp, and a ''78 M II coupe 2.8L auto. And of course 6 Ford Capris.
Later. Pepse.