redtop spools but boost doesnt make it to the wheels.

[unwtdhero]

So i got this car a month ago, and all it needed was a alternator. So i ordered one off here and installed it and it works, but heres the problem. I thought i had a boost leak, but my gauge says vacuum lowest : 20; Boost highest:7.
So alls good except when i drive every gear the bov (hks ssqv2) always whistles. And none of my boost is reaching the wheels, and my clutch seems to catch very well (stage 3). So help pleeze, i have searched but nothing is of help. thanks yall.