This one goes in your mouth, this one goes in your ear, and this one goes in our butt. Hang on a second....
OK, someone please explain this photo. Does it run backwards? Using the larger exhaust valves for the intakes? Are those HOnda 750 carbs? Was this on purpose? Is the distributor running off the waterpump? inquiring minds want to inow.
One could also ask: "Does it even run - or is it just a show mock-up?" That being said, only a re-machined cam would be required. Looking at this setup, I don't believe performance was the goal, likely the intake is going in through the small valve... Does are just assumptions, of course.
The distributer is driven off the camshaft sprocket. There are some old-school dragster applications that did that, but what I can tell from the pic looks homemade. No water pump in the standard location. See the black fittings pointing down on the front of the block, and the ones coming in the back of the head? There's probably an electric inline water pump somewhere under the car. Even if it's a 283 that's 2600cc a bank. Carbs about have to be too small and CVs with no air box or even filters are never going to be 100% right. It probably runs just well enough to start and putt around car shows.