Installing the Nelson/Paxton EFI Supercharger System
by Travis Shrey

     Rotaries love force-fed air.  Limit the amount of boost you'll run to under seven pounds and you can make do without an intercooler.  While seven pounds doesn't sound like much for a Turbo II, the 6-port NA engine uses higher compression rotors and, with the secondary intake ports open, offers considerably larger intake duration and flow to work with.  If you can manage to keep your foot out of it, your fuel consumption won't drop a bit; when you want to get on it you'll be rewarded by the kind of acceleration only modified TII drivers get to experience.

     The image at right is a picture of all the parts included in the Nelson package.  You can see the Paxton unit, the aluminum mounting bracket, the fuel pressure riser, the new serpentine pulleys and belts, the top radiator tube (with aluminum water neck) and the new throttlebody elbow and horn.  Also included are the flexible airpipe from the air filter, the rubber elbow for the supercharger intake, as well as a heat shield for the front sixport.

     The first thing you'll want to do is remove the alternator pulley and eccentric shaft front pulleys (3) and replace them with the included aluminum serpentine pulleys.  Then remove the alternator, lengthen the wires for the plug on the back, and rewrap your wiring harness (on 10 year old cars they get brittle - be gentle!) and run it under the throttlebody and secondary fuel rail.  Remove the water neck and upper radiator hose (now is a good time to replace the thermostat) and install the aluminum spacer and new water neck.

     Remove the aluminum mount for the airpump and use the three bolts to mount the new supercharger/airpump bracket.  It is now critical to align the pulleys for the serpentine belt; mount the supercharger on the bracket.  Using a straight edge, project from the face of the supercharger pulley to the alternator pulley.  You'll probably find that the supercharger needs to be spaced back - in my case it was quite a bit.  Using the spacer washers mount the supercharger so that the face of the pulleys are lined up.  Because I had to space it back so far, the mounting bracket needed to be ground out to allow for the oil fill tube on the supercharger.  The same things must be done with the airpump if you are running tree-hugger friendly.  Mount the rubber elbow on the back of the supercharger and run the 3" flex tubing up the the AFM and connect.  Mount the new throttle air horn on the throttlebody and the connecting elbow from the supercharger to the air horn.  Install the new top radiator tube and fill with coolant.

     Next you need to find a place to mount the included fuel pressure regulator.  Under boost the FPR cuts off the fuel return flow, effectively boosting the fuel rail pressure.  I mounted mine on the bracket made available when one removes the cold-start assist reservoir and pump.  The return line from the engine goes to the IN nipple, and the OUT nipple gets connected to the chassis return line.  Be sure to keep fuel lines away from metal edges - especially if you're mounting the FPR on the same side as the exhaust manifold.  A leak would be bad, to say the least.

     Tighten the serpentine belt using the tensioning pulley, recheck all connections, fill the supercharger with oil, and fire the car up.  When the supercharger is new it is very hard to turn.  After about 200 miles it gets much easier; until then it may be necessary to increase the car's idle, especially if you've gutted the throttlebody like I have.  Make sure you don't have any fuel or coolant leaks and take it for a test drive.