Tom Lowe on Inliners.org is the one to talk to. A few years back they did a hugh dyno thrash with a 292 and 250 swapping every cam and intake they could get. Ask for the results and some turbo information. He runs a turbo 292 all the time. At one point someone on the same site gathered all the 250 292 cam spec's that were and still are available and posted them in a nice organized spread sheet. Try and find that for reference.

Joe