From someone who has had both Powerdyne's, the BD-11A and XB-1, I would say the BD-11A isn't a bad entry level blower but you will want more soon enough. You will hit the potential of the belt driven BD-11A real quick as well. Don't get me wrong, it can make decent power but it's rated at 800cfm at 9psi. There are a few people out there running them way beyond their potential but many do so using upgraded internal bearings and belt. If you go Powerdyne, I would go with the gear driven XB-1. Equal to the S-trim and perhaps then some. If costs and oil tapping is an issue, the P1SC might be a good bet. At least then you have room to grow.
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There are only three things the copilot should ever say:
1. Nice landing, Sir.
2. I'll buy the first round.
3. I'll take the ugly one.
Powerdyne Supercharger Kit for 1986-1993 Ford Mustang GT/LX with 5.0L (Complete 9 psi Kit w/By-Pass & Fuel Pump) (satin)
$2,699.00
ProCharger P-1SC-2 High Output Supercharger Kit (NON-INTERCOOLED) for 86-93 Mustang 5.0L (NMRA Real Street Legal | 8-Rib | 6-20psi)
$2,499.00
As you can see the Powerdyne is not as cheap as it looks, the ATI is a much better blower for the $.
Some info about the ATI:
These revolutionary new SC ProCharger models are the first and only gear-driven centrifugal superchargers to feature self-lubrication. The SC models share many of the design elements which deliver the record-setting durability and performance of ProCharger competition superchargers, and are also quiet and street legal. The P-1SC is the most popular automotive supercharger, and with its rugged design is the only self-contained supercharger durable enough to be backed with a 3 year warranty (not available on all systems) and powerful enough to harness the benefits of intercooling. The patented design eliminates the need for oil lines and tapping the oil pan, thanks to its exclusive oil pump, which aerates the oil to create the oil mist lubrication required by the precision bearings and gears. This oil pump (aeration pump) does not require priming at start-up, and oil changes are required only every 6,000 miles. SC ProChargers also feature an internal step-up ratio of 4.10:1 for improved belt tracking and traction, and are cast with permanent molds for the highest quality finish.
Thanks to this new technology, the industry leading power and durability of gear-driven centrifugal superchargers is now available without tapping into the engine oil system. The P-1SC ProCharger supports up to 1200 cfm and 825 horsepower, and has been rigorously tested for load and continuous duty. The P-1SC features a radial impeller for its optimal combination of average boost and efficiency, and is available as an upgrade to the P600B.
I just put a Powerdyne BD-11A and ran a 13.22@108.8 seeing 5psi shifting at 5000. I would went to 5200 had the car not been so hot. I love the SC so far and the install was easy. I got it used for less than $1000 with only 500 miles on it!! BTW, you can buy a 9lb kit for $1900-2000 from most places online or you can buy it has the 9lb Ford Racing Parts SC kit. I was concerned at 1st with all the bad talk abou them on the net but it really performs well. My friend used this sam SC on his car and ran a 10.81@126.7 with a 13lb pulley. The ProCharger is very nice, but I've also heard they leak too. So hard saying. I think you can get a ProCharger for like $2200 on the net too new. They all do the same thing, I just didn't have the $$ for new one and this was good deal for me. I'm happy!
I bought my Powerdyne new for a SN95 (usually a bit higher than the fox kits) for just under $2100. I got what was the equivalent of the 9lb kit (that usually lists for $2400-2500) without the computer chip. The chip isn't very good.
So it was the 6lb kit with a factory 9lb pulley swap, By-pass valve, and 255lb in tank pump. The kit has all the brackets, hoses and fmu. I picked up a used Vortech fmu with adjustable discs.
I've so busy with other things that I have not installed it yet
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95 GT Convertible
BBK shorties, X-pipe, Magnaflow CB
CAI, 70mm TB, GT40 intake, 1.7 RR, UD pulleys
SFC/braces/JR, AUC Arms
1966 C Coupe - New restoration project
2004 Chev Silverado 4X4
I've been running my PD for about 30K miles now and am very happy with it. I bought it new in '97 for $2150 as a 9# kit with a 6# pulley. Once I had it running right (timing, fuel pressure, etc.) I put the 9# pulley on and a big smile on my face.
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Black on black '95 GT ‘vert, 9# PD, AFR 165’s, Cobra intake, 65mm TB, Lightening mass air, 42# injectors, 190 pump, 1.7 rockers, X-pipe, Flowmasters, 'Z' trans , 3.27's, KB subs, Bilstein shocks/struts, H&R race springs, MM LCA’s & CC plates, Cobra brakes, Cervini's Stalker kit, S281 wing.
Powerdyne 87-93 S/C what you think? 
BTW, you can buy a 9lb kit for $1900-2000 from most places online or you can buy it has the 9lb Ford Racing Parts SC kit. I was concerned at 1st with all the bad talk abou them on the net but it really performs well. My friend used this sam SC on his car and ran a 10.81@126.7 with a 13lb pulley. The ProCharger is very nice, but I've also heard they leak too. So hard saying. I think you can get a ProCharger for like $2200 on the net too new. They all do the same thing, I just didn't have the $$ for new one and this was good deal for me. I'm happy!
Seeing 6-7psi on cooler day...better hookup..
