KB Twin Screw

[Mr.VENGEANCE]

how bout on an LS7?

[thetoystore]

how tall is the kb supercharger?

[67 ls1 vert]

Droolguy
I did not do any cutting to get mine to fit. Im sorry, my keyboard is old and the keys dont work well anymore.

[Droolguy]

The KB twin screw is fairly compact, they fit under classic car hoods without any real effort at all.

If I had to guess I would say they are less than 5 inches tall.

[calforniacuda]

Many of the KB or Whipple s/c's bring the intake air in through the rear of the unit, helping with height. The old roots designs had intake air coming in throught the top.

[1970 TT Rustang]

roots are 3 lobe and screw are 4 lobe and more effecient

[CarlC]

roots are 3 lobe and screw are 4 lobe and more effecient

The latest generation of Eaton superchargers are also four-lobe designs.

[DeltaT]

Twinscrews have internal compression. Roots (including the twisted vane) are air movers only - all compression is done in the manifold as a result of packing in more air than can be consumed by the motor at a given rpm. The twinscrews also do this, but their internal compression gives them an efficiency boost which results in a lower amount of heat per pound of boost as seen by the motor.

Not all twinscrews are four lobe. The KB are four lobe on the male side, six on the female. The Lysholm and Whipple (and now the Vortech version which is from Lysholm) are 3 lobes on the male and 5 on the female. The internal compression on the twinscrew is the result of air getting trapped between the rotors and actually being compressed as the volume of space (due to the unique shape of the screws) gets smaller. In an ideal world, the twinscrew should produce about 1.4 times the boost for the same heat as the Roots.

Eaton makes their efficiency charts for the TVS units a little better than ideal, because they do not take the power needed to drive the blower into account on the charts. The Lysholm charts do. People will hold up the Eaton charts as 'proof' that the new TVS units outperform a twinscrew, but testing with the same size unit has shown that the twinscrew outperforms by a good margin.

Jim