This Bounce spring kit is intended to be use with a basic Seat and Guide machine or a Bridgeport type mill.

The springs are very stout, takes 30 lbs pf pressure to deflect, this helps to have a better control on cutting head, eliminating the "Roller coaster" effect and it's damping action helps control chatter.

Note: This kit will fit .375" and .385" top pilots only.

7 different Delrin bushings to sort out different situations, there is one special bushing for small tip holders and two spacers/extensions for deeper runners, also an aluminum ring stop for heads that have been ported and have an uneven valve guide boss, this stop rings provides a flat all around surface for bounce spring, which helps on seat concentricity.