I don't see why the intake is limiting, why not just do the 400g hack, I run speed density on a 65mm also on my vf37 on e85 making 340/340 consistant on mustang and airboys that's at 26 tapering to 23 no restrictive wall, it really sounds like when I had my vf37 with a 20g wheel, and the compressor wheel overflowed the exhaust wheel. What goes in must come out.