I have to concur with Pat - a 350 is just not designed for the kind of grunt a blown BBC will generate, no matter how light you tread on the gas. All it will take is one good lock up where the rear tires bite down and you be calling a tow truck for the ride home and the street sweeper to recover what's left of the transmission.

Even a very well built 350 is limited to the 450HP range on non-blown motors..