Originally Posted by Mohavvalley

Those 8-71 are on 525sc, same set up I got, and MT has interesting in HP differences.

So to conclude I could run them but it's still be restrictive and hurt HP, would you recommend 800's

Originally Posted by compedgemarine

when talking roots style blowers you need to understand how they work and what they are designed to do (as was said above they are air movers). the blower comes from the old detroit V series diesels. those motors are two stroke. the only reason for the blower was to move air into the cylinders as the two stroke setup had no intake vacuum in the intake and without the blower it wont move enough air on its own to even start. later with the V92 series they added a turbo to build boost and the last version had a bypass so the boosted air would bypass the blower as it then became a restriction. they then got adapted for hot rod use and other than helix rotors are basically the same. the air moves around the outside of the case and meets back at the middle so they are not really compressing any air, just moving way more than the motor needs so it makes boost. as such they were never designed to have fuel stuffed in there at the same time as the air so it does not control it well, again as was stated above. the more evenly you can distribute the fuel the less the blower screws up that delivery. the issue of boost is one of the things that always bothers me when people say " I want to run 10 psi" or whatever. boost is a reference only. a motor with small intake ports will make lots of boost and no power while a motor with big ports and low boost will make lots of power with the same blower and pulley setup. this is why it is so important to build the whole system together as a opposed to just throwing a blower on in hopes of making big power. just my two cents tho.