From that day forward, a 15-inch rotor blower is called a 6-71, a 16-inch long rotor is called an 8-71, and a 19-inch long rotor is a 14-71 blower. As you can see, the bigger the number, the longer the rotor, and the more power it will make.” The Screw Blower.
What do the numbers mean on a supercharger?
In terms of sizing, it all comes down to the volume of air that the supercharger can cram into the cylinders of the engine each time the supercharger spins around. The ratings for superchargers are therefore given in L/rev (litres per revolution) or cc/rev (cubic inches per revolution).
What is a 10-71 blower?
Littlefield 10-71 polished alum. competition blower. This blower has nylatron and Teflon stripping to insure maximum efficiency on your engine. Rotors are billet and hard anodized for a long lasting supercharger and a tighter inside tolerance creating a more efficient supercharger.
Why is it called a 6-71 blower?
GMC 6-71 Blowers
In 1939, they finalized development of a 2 stroke diesel engine with six cylinders (among others)of 71 cubic inches each (totaling 426 cubic inches, coincidentally). It was called a �6-71�.
What is a 6-71 blower?
In GMC diesel nomenclature, 6 represents the number of cylinders, while 71 represents the cubic-inch displacement per cylinder. So the displacement here is 426 cubic inches, and that is the approximate displacement of the blower as well.
20 related questions foundHow much does a 871 blower weigh?
The blower is drilled six spots in the rear for fuel with the top opening measuring 10.50" inch to provide maximum boost. This blower can be moved back on the blower manifold or run in the stock location. Blower can be ordered polished for an additional $300.00. Blower weights 80 lbs.
How much boost can a 6-71 blower make?
Driven 11 percent under, the 6-71 produced a boost curve that began at 4.2 psi at 3,300 rpm and rose to 8.3 psi at 6,400 rpm. This pulley combination produced peak power numbers of 602 hp at 6,400 rpm and 551 lb-ft of torque at 4,700 rpm.
How many liters is a 6 71 blower?
The GMC 6-71 diesel engine with corresponding 6-71 blower was frequently used as a truck engine, marine engine, or generator power source or a pump power source. These units are 7.0 Liters, 426 cubic inches, and rated at 190 HP.
How many cubic inches is a 671 blower?
A 671 pushes through 426 cubic inches.
Is a blower the same as a supercharger?
– While the purpose of superchargers and blowers are basically the same – to pump air into the engine at a rate that is beyond the force of atmospheric pressure – superchargers are driven mechanically via the belts that run off the crankshaft or by an electric motor, while blowers use centrifugal force to push the air ...
What is a Helix supercharger?
Hi-helix blowers are defined. as any supercharger with a rotor twist greater than. 60 deg. Overdrive limit only applies to 14.71 size.
How does a Roots blower work?
What is a “Roots Blower”? A roots blower pump is a positive displacement rotary lobe pump that operates by pumping a fluid with a pair of meshing lobes not unlike a set of stretched gears. Fluid is then trapped in pockets surrounding the lobes and carried from the intake side to the exhaust.
How much boost does a 871 blower make?
Our first whack with the 8-71 used a 63-tooth pulley on the top and a 54 on the bottom for a drive ratio of 0.857:1 (14.3 percent underdriven) making peak boost of 7.6 pounds at 5,900 rpm and delivering 724 lb-ft at 4,800 rpm and 754 hp at 5,900 rpm.
Do superchargers make boost at idle?
Inactive. The supercharger will not make boost at partial throttle because it is sucking air through the thorttle body. The bypass valve is just to improve efficiency at partial throttle.
What is a good compression ratio for a supercharger?
The optimum compression ratio is 8.0:1. Higher than 8.0:1 is not necessary or recommended. Fuel, ignition timing, and total boost could become critical factors.
How do I know if I have a 6-71 blower?
Another dimension to note is that a 6-71 rotor is 15” long, the 8-71 rotor is 16” long, a 10-71 rotor is 17" long, a 12-71 rotor is 18" long a 14-71 rotor is 19" long and the 16-71 rotor is 20” long. All rotors are the same diameter with the exception of the small rotor 6-71.
How many Litres is a 6-71 supercharger?
I.e. 6-71 is 3.0 liters or an 8-71 is the same as a 4.0...
What is the difference between a Roots blower and a screw blower?
The screw blower may look similar to a roots blower, however, it functions differently. The roots blower acts like a pump for the air as it goes into the motor, whereas the screw blower is more like an air compressor in how it forces the atmosphere into the engine.
At what RPM does a supercharger kick in?
The supercharger begins increasing intake air pressure just above idle. Between 2,500 and 3,500 r.p.m. both blowers work cooperatively to boost the intake air to a regulated 22 pounds per square inch above atmospheric pressure.
How much horsepower will a blower add?
Blowers make horsepower and lots more torque than a standard engine. The amount of extra horsepower really depends on what your engine is like. On a 350 Chev, Weiand estimates an extra 100-120hp with one of its low-blow superchargers on an otherwise stock motor.
Why does a supercharger whine?
Superchargers are driven by a belt connected to the engine crankshaft. This means that they spin at a high rate of speed, which can create a whining noise. Another reason for the characteristic supercharger whine is because of the way air moves through them.
How much HP can a 8 71 blower make?
5. The biggest chunk of aluminum was, of course, the polished 8-71 from The Blower Shop. Capable of supporting over 1,000 hp on the right combination, the 8-71 looked right at home on the BPE 540. 6.
Does a roots blower compress air?
How Does a Roots Blower Work? Roots blowers are typically oil-free, air-cooled technologies comprised of two rotors that spin in opposite directions. Once the compression chamber comes into contact with the outlet port, compressed air flows back into the housing from the pressure side.
Why do they call it a roots blower?
The Roots-type blower is named after American inventors and brothers Philander and Francis Marion Roots, founders of the Roots Blower Company of Connersville, Indiana USA, who patented the basic design in 1860 as an air pump for use in blast furnaces and other industrial applications.
