TBS XR Race Inserts are crafted from billet aluminum in an array of sizes.  Meant to change when boost is activated, a smaller opening boosts quicker and a bigger opening produces more boost on the top end.  A quick way to tune your blower at the track, these inserts are available only for the race series blowers.

Available in:

• 11"
• 10"
• 9"
• 8"
• 7"
• 6"
• 5.5"
• 5.35"
• 4.50"