KB Performance, 96" to 103" big bore piston set. +.040"

07-17 Twin Cam (NU)

For 96" to 103" (3 3/4" to 3 7/8") big bore conversions. Used with stock heads and cylinders. By boring the stock cylinders from 3-3/4" to 3-7/8" big bore size engine capacity will increase from 96" to 103". Comes with T6 heat treated 390 Hypereutectic cast pistons with 16% silicone levels which enables running a very tight clearance for longevity and hardly any piston noise. 10.0:1 CR with 85cc head. Head type: Flat top. +1.9cc / Compression height 1.076". Bore 3.875" / Stroke 4.375". Rod length 7.667". Note: Top compression ring will need additional clearance. See instructions.