Man, that's gotta be the BIGGEST turbo I've ever seen on a 750.
The one I knew here in Denver, on a K4, was about as big as my fist, 5 PSI boost max. It was like yours, sucking the carb through the turbo. It was a 40mm Mikuni with jets the owner drilled himself, and an intake manifold made of smallish round tubing: his idea was that since it was boosted, the intake tract size wasn't all that important. I only got involved because he would run low on fuel in the float bowl after a few seconds of on-boost run (about 1/4 of the way down the track). We ended up fitting a small fuel pump with a bypass relief valve right at the carb, set at 4 PSI (I think), from a snowmobile, if I remember right. It got him into the 10s, too, so he was doing something right.
Then there was the one on the CBX I saw at Bandimere's strip one night: it was about the size of yours. The exhaust ran right in front of the timing plate, so the owner made (had made, actually) a very expensive billet piece with a drive and sprockets to raise the ignition up alongside the engine's fins. Then he used POINTS and a points cam! Man, that CBX was one track-burning streak, too, with beautiful fittings everywhere and even chromed piping. Rumor has it this bike is in Hudson, CO today.
Two of his buddies rode a pair of identical CBXs around here on Saturday nights (they used to work at the old Fay Myers on Alameda, for you Denverites), smoking the rear tires just for fun!
I hope you get it running: what a blast it will be!
