ANY SUPERCHARGER GURU's out there?

[bull the rogue welder]

i'm pondering the installation of an overdrive pulley on my weiand 174 blower on my 454 .
right now my pulleys are 7" crank and 3 1/2" nose. the specs on the motor are 8.4:1 static flatop forged pistons ,750 demon BC , dyno'd 568 hp /575 torque @ 6700rpm with 5psi boost. = 12.1:1 compression
going to the 2 1/2" nose pulley will i have enough blower for that motor? or will it spin to its max and the motor will starve for more? if the blower could keep up will that put me off pump gas?

[squirrel]

I dont know about how that'll work out with it spinning that fast...might be near the point of diminishing returns?

Also that's not much carb CFM for a blown big block.

[SuperBuickGuy]

IIRC there are 142, 144, and 177 blowers.

That said, I had a 144 on a 406 that I went to a smaller pulley to get higher boost (from 3 1/2 to IIRC 2 5/8). It did provide higher boost, but it added a lot of extra heat and detonation. The B&M blowers are just not that efficient, so they work great on a motorhome or pickup where you want an extra 100 hp to pull; but you start spinning them tighter and the law of diminishing returns starts to apply.

That said, there is a solution. A chemical intercooler... Nitrous. Adding nitrous to that mixture cools the charge in addition to adding another 100 hp. I'd avoid the methanol intercoolers because they don't give you the same bang for buck (they don't cool as much as nitrous). Preferably you'd put the nozzles under the blower to avoid trying to force more air in an already crowded space.

You have a concern about providing enough air - the short answer is it will even with the 3 1/2 pulley. You can pull the belt off (or have it come off under boost while trying to sell the car) and it will run, but it will run quite sluggish.

[bull the rogue welder]

i'm happy with the setup i have i was just curious about the smaller pulley i'm getting the hp and torque i expected thats plenty of carb for that setup i think..... i dont want to have a gas tanker following me around everywhere i take it.

[JoeyG]

I gotta agree with squirrel, the pulley change will net you 2-4 more lbs of boost but the blower is gonna turn into a microwave of heated air. You might be able to get by with a plate methanol kit but then your kinda moving into a band-aid effect for not that much benifit from the get go.