The FRPP crate engines are essentially stock parts, so they'll hold boost as well as a stock engine would. For the price of one of those engines, you could get one from a quality builder such as CHP, DSS, RNH Performance (Rick 91GT on here) and have a better foundation to work with.
yea talk to Rick he build's and races them and you know he knows what he is doing. Tell him you want to run boost and he might know some secrets to help with that.