If the intake is a 4 hole style you can modify it into a "twin oval" set up with open right and left sides. Adds a little plenum volume and allows the air/fuel to make a slightly gentler turn into the runners.A port match to the heads couldn't hurt either. Do the heads have the 1.6" exhaust valves? You could go up to the bigger ex. valve for a little gain.Recurve the distributor to get all the timing in as early as detonation allows.Play with carb. spacers.