All supercharger brackets attach via alternator attach bolts. you need longer than stock alternator bolts and lots of miscellaneous **** - it's not fun.
Anything is possible
You guys are saying CF blowers aren't good - etc, but what they do is make power reliably. There is no guessing whats going to happen at 4k rpm - the engine picks up linearly and all is well.
Roots blowers can be somewhat unpredictable. They're always making boost so when you first rev it up theres a instant "shock" to the motor that has the same effect when shifting sometimes... its a noticeable difference from a CF.
A twinscrew is the least "noticeable" setup. The rotors spin compressing the air - the rotors are often coated with teflon and have like .001" of gap. The rotors DO wear, and need to be refinished eventually. There are several makes of twinscrews...eaton makes on and whipple makes one. The power band on a twinscrew is much different than on a CF or Roots. The TS blower acts like a larger motor. The torque curve is the flattest thing - people often think you're dynoing a large V8 when dyno'ing a L6 with a TS.
The only downside to a twin screw is that it replaces the intake manifold. This means there is no room for an intercooler. Some kits replace the intake manifold with an inline air to water intercooler - some don't. Some people have been successful fitting the Eaton blower from mercedes c230 kompressor motors into BMW 318's (e30). However, it doesn't mount on the head like that, but rather ghetto all over the place with plates that convert the direct runner into a collector etc.
A lot of VW guys use Lysolm or Autorotor kits. They were so badly they only get about 6k miles before the blower is leaking boost inside to outside. You can see in the above picture how "unbulky" the actual main body of a twin screw is. All the seams are prone to opening.
The kit pictures above is the Eurosport kit, which sells for about $7,000 uninstalled. It replaces intake manifold including the fuel ports. Is it worth it? Max power out of them tends to be a little lower than CF units, however CF units only make their peak power at peak RPM. I am turning 9 psi @ 6500rpm. I have a max of 7200 RPM rev limiter which would be well over 10 psi - 11psi. The twin screws are only running 6 or 7 psi, but its constant. The power is everywhere and not just up top like a CF unit. Some people like that, but i actually prefer getting kicked in the butt at 5000 rpm.
Also! The unit you pictured in the first post is a Powerdyne unit originally used by Dinan and some RMS kits. These blowers are HORRIBLE. If you find one on ebay, run. You can see the buldge on the front of the unit - that is the drive belt. There is an internal belt in there that links one wheel to another, so the turbine spins. This belt breaks OFTEN. It's a real pain and generally not efficient as they leak boost out all of the orifices etc. I am using the ASA supercharger... its internally geared 15:1 compressor:drive pulley. Geared superchargers are MUCH preferred over belts - there wont be a chance of a belt breaking.
My blower:
By the way, if you are doing an M3 crank in a 2.5 block you need 3.0 or 3.2 rods as I recall... which is kind of a bump in the wrong direction if you have a NON VANOS motor.
Oh one more thing... about the remote mounting of the twin screw. ALL the pressure on the blower will be at the pulley, so with a long neck, the TS has a dendency to dip if mounted on a bracket. This causes angle at the pulley and throws belts a lot. Ask any 318 owner with the eaton setup. the manifold replacement method is much more sound. I only threw a belt once, and it was when I was pissed off.
One more edit: TS set is making 350 hp on OBDII 3.2L M3. There are CF guys making over 450hp. The TS kit is also $8500, not $7k as previously stated... and thats $8500 uninstalled.
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