11" High Performance High Stall speed converter for 727 Mopar Torqueflite transmission. 2400-2800 rpm stall speed range. Great for street and street strip cars. Improve your launch, get quicker ets and better mph. This JW converter gives great efficency as well as higher stall speeds and greater torque multiplication. If you will be using this with an external balance crank we can add the correct balance weight to the converter before shipping for a small additional charge. If you need the crank set up for external balance, please e-mail us when you order and let us know what engine size you will be using, and that you need it set up for an external balance crank.