I think Tim is spot on about the pipes. When Carleton was running there was no silencer requirment in the rules. Now there is, so most of his exhaust system development is out dated for me. Terry's Mk4 cams are available.
Terry has had a raft of health issues this past year. He fell down an embankment, the tire on his bike exploded on the dyno and a chunk hit him in the head and he recently had an operation that was more involved than he had hoped. Despite this, he will be at Bonneville and the Rally. He will be with Pat Manning much of the time.
John, it sounds like a good set up. Carleton used John Renwick's cam, which I also had in my engine, which makes power up high, but more importantly, it does not drop off quickly. John does not sell retail because he makes them himself and he cannot do the quality necessary for such sales. Carleton and I have 500cc Prince heads, not the 600 ones. I have not used it as it is illegal in some of the venues that I run. If you run Vintage, you have to have original cases, cylinders and heads. They are not illegal in AHRMA road racing, so Carlton used his road racing. There were still a lot of hours and money spent to make that head flow. As I remember, the intake was pretty easy, like one day on the flow bench. He then spent more than a week on the exhaust port trying to balance the flow.
David