I'll take my roots blower any day, first reason for the looks (wow factor). It may not make the peak boost of a centrifigul but I make max boost by 2k and hold even all the way to 7k. As for them not taking RPM I have had mine since 1989 on two different motors and have turned it 8k before. There is not even a blemish on the rotors. Maybe Holley has changed some stuff, mine is an original B&M but they look exactly the same. If it were me I would build a blown stroker.

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69 Mustang 331cu in DSS level 20
TFS track heat, DSS rockers, lift:.573 .276, Bigs 750, MSD 6AL & billet dizzy, B&M 174 @7psi, AOD 3.5k stall, 9" 4.11