42671 Pro Race Under Drive Harmonic Balancer and Pulley Kit - Ford V8

Accessory drive systems have been made more compact on Late Model V8 engines like the Ford 4.6L and the GM LS1 by machining serpentine belt grooves on the OD of the crankshaft Balancer. The crankshaft Balancer functions as a combination crank Balancer and crank pulley on these engines. Under drive Balancers are smaller in diameter than stock production crank Balancers which slows the speed of the accessories and reduces the HP required to drive them. Since performance and racing engine applications generally run at higher RPM, the water pump, alternator and power steering pump speeds can be reduced to save HP and still meet engine cooling, electrical and vehicle steering requirements.

Note #9 This Kit includes a Balancer, a pulley for the short shaft water pump, alternator pulley, new crank bolt, alternator bracket bolt and an installation bolt. OE Belts to be used.