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Ok, so I am VERY new to forums but I need a little advice.

I have a highly modified 408w in a 1996 Cobra. I have built this car from the ground up. I recently bought a complete powerdyne bd-11a with a billet impeller from a friend for $150. To cheap to pass up. It's currently being rebuilt (belt, seals, and bearings).

My question is this... I have read through these forums that this supercharger only makes 400-500hp but I'm certain that I make more horsepower than that without the supercharger. Is it possible for that to be a problem? I also plan to run an intercooler and piping for it as well as an air cooler. I built this engine for boost with girdles, APR studs for everything, and dish pistons.

I know that everyone says that powerdyne is practically junk but for less than $500, I won't complain.

Thanks guys.
 

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a supercharger makes 0, zero, horsepower

it moves air at a certain pressure

you need to find out what cfm it can move at what pressure

then compare to your engine

the sc must move more air than your engine to create higher than atmospheric pressure into the cylinders
 

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x2 ^^what he said

if you want real world results

My cousin has a 95 gt, it had a stock bottom 5.0 in it with a set of trickflow heads and ported gt40 intake. With a junk s-trim vortech or the like cant recall exactly. It made 301rwhp n/a and made 585rwhp at 17lbs of boost with the blower maxed out spinning the piss out of it. Inlet temps were over 320 degrees without meth (non interooled). I had to put a 15gph and a 20 gph meth nozzle on it spraying in to the blower to keep the ACTs around 120 degrees.

that engine lasted about 10 years and well over 500 passes with daily driver duty for most of its life. When she cracked one of the stock hyper pistons one day sitting at a redlight he ripped the stock 302 out and tossed in a 393 all else being the same other than a super victor intake. The engine now made 330 rwhp n/a and at 14lbs of boost (same pulley) still put down 586rwhp. The junk chinese crank he had snapped on startup one day when i was daily driving it. We put my spare 408 rhs headed engine in it that makes 390rwhp n/a and at 9 lbs of boost (same pulley still from the original 302) it still put down the same 591rwhp.
 

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Don't bother - that thing will likely be a restriction on your motor. I'm not sure what you mean by "highly modified" but if it's anything like my definition of the same term, then even if you do manage to make any boost, it'll likely be so far off the compressor map you'd still make more power N/A. A blower's compressor map not only tells you how much air it can move at a certain rpm, but it also requires a certain PR (pressure ratio) to work efficiently. I can't find a map for that thing, but here's one for an S-Trim:



A BD-11 on a healthy 408 will probably way off the map to the bottom right. You'll need to spin the ever loving ##### out of it to get a 1.1 or 1.2 pr. Efficiency will be horrible. But it might make a little more torque - at least until it starts losing power (vs N/A) up top.

I'm the master of undersized blowers - I've learned about all the bad things that can happen the hard way. This one will likely grenade itself and send junk through your motor before it gives you any useable power. If you can even find a pulley combination to make any boost.
 
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