current MBC to one that sounds like it will work better. So I'll look for one that has less air bleed to control boost, and a quicker boost response. My current one holds 30+ psi, so I don't think I'll be able to improve on that function. I'll look into the Hallman. As an aside, did your belt squeak just start, and do you have an underdrive pulley (chrome or some super smooth surface)?