Don't know about big boost, but I'm building a RB with twin 72mm turbos. They should b egood for about 25 psi. Still waiting for the pistons... but after that it will go together and most likely driven this summer. It's based on an Indy RB block, 4.25" x 4.5", CR about 8.8:1, air to air intercooler, roller cam with 270+ at .050", FBS heads and a sheetmetal intake. Here is a couple of pics of the intake being built.