A lift bar is the rigid rear torque link on a dirt Modified or Late Model. A pull bar does the same job but carries a spring, puck or Belleville washer stack, so the bar can give under load.
These names are not standardized, and you will hear lift bar, lift arm and pull bar used loosely. The clearest line comes from the parts catalog. Wehrs Machine files lift arms and pull bars as separate product families, and calls one part both names — “we’ve taken the lift arm to the next level with this two piece billet beauty” — with a heim-adjustable top arm for pinion angle and 5th-coil mounts at 29, 31, 33 and 35 inches from the axle tube. Their pull bars are the opposite idea: spring, puck and Belleville-washer versions, one built to “accept a 2-1/2″ spring or up to a 3″ puck,” sold on the promise to “build any rate curve you desire.” Ask your chassis builder which yours is.
A lift bar and a pull bar manage the same torque two different ways, so setup advice written for one will move your car the wrong direction on the other.
Read the full post:
Panhard Bar Adjustment and J-Bar Setup: How Height and Angle Change Your Car