I put a lynx adapter and a dual throat weber carby off an xe or xf falcon on mine years ago. Gave it a fair bit more top end, and was bloody cheap. Also had extractors. I had a friend with the same car and this put me fairly solidly ahead of him.
They use these in sport trucks in cali etc for years and the americans, (who also had the turbo 22rte) made a lot of carby/inlet manifolds for these and the 22r. Look in the states for good tuning on these engines. The most common build seems to be a 20r head on a 22r block.