RBS is proud to offer the legendary Fowler F-11 supercharger line. What is a F-11 you may ask. Well it is one of the most innovative supercharger that have come out to racers in a long time. The F-11 design, which went into production in early 2001 on 14-71 units, brings added elements of performance and safety to the racing world.On all the Superman style units, the front bearing housings have three inches of billet material that are press fit into the rotor case and push the rotors back in the case allowing the air to come and load the front of the rotors providing a smoother transition of airflow and providing more boost and cooler air as the air does not get so beat up entering the blower. This bearing plate design increases the strength considerably over the common dowel pinned bearing housings normal to most supercharger designs. The rear cover is also captured in the same way. This design also benefits repeatability of rotor location. As these units are overhauled, the doweled design tends to wobble out the bores and the rotors find themselves misaligned over time, which can cause supercharger malfunction. This blower uses precision caged roller bearings in the rear and precision ball bearings in the front as well as double lipped teflon seals for superior sealing. RBS is proud to offer the newest in F-11 rotor design to help give you the winning edge. This unit is available in a 6-71, 8-71, 10-71, 14-71, 16-71 and are you ready for this 18-71. This blower can be ordered in a standard 60 degree rotor or a 120 degree hi helix rotor depending on the use. RBS can help the customer choose the best supercharger for your application. The snout is included and you get your choice of 4.00" or 5.00" depending upon your application. BLOWER WITH FIVE INCH SNOUT WEIGHTS #138.00. Measurement on the 14-71 for the guy wanting to see if it will fit with firewall or windshield from center of rear blower stud hole on the 2, 4, 6, 8, side of the engine it is 10.50" to the rear bearing cap.