It is recommended that all supercharged LS engines have their crankshaft and balancer either keyed or pinned. Some aftermarket crankshafts and balancers come with keyways machined into them whilst the OE engines do not. If they are not keyed or pinned the harmonic balancer may spin on the crankshaft and cause damage to the crankshaft and balancer.
The kit will enable to you precisely drill your crank and balancer, allowing you to place the pin between them.
