S&S Cycle · New
S&S Cycle 84-99 BT w/ Stock Heads 88in 3 5/8in Big Bore Cylinder & Piston Kit - Wrinkle Black
MPN 91-7502 · Store SKU ssc91-7502
Supplier stock checked 11/8/2026, 4:37:40 AM UTC. Adding a part does not reserve it.
Request a return within 30 calendar days after delivery. New parts must be unopened and unused.
Shipping & returns ↗This policy does not limit rights required by law.Free standard shipping on eligible parts orders of $100 or more. Oversized and freight items excluded. Fitment, taxes, availability and final totals are confirmed before payment.
Product details
This 3-5/8" big bore kit will increase the displacement of stock 80" Evolution big twin engines to 88" using the stock 4-1/4" flywheels. The kit includes S&S 3-5/8" borecylinders, 3-5/8" bore flat topped forged pistons with rings and wristpins, head gaskets, base gaskets, exhcaust gaskets, and instructions. The cylinders are shorter than stock, so shorter pushrods, and shorter manifold will be needed to complete the engine. Stock cases will need to be bored out to 3 5/8".
Manufacturer fitment & guides
Check 91-7502 against the manufacturer’s application information below.
A manufacturer application guide is not available for this listing. Request the exact application from JuiceBuilt before payment.
Part-specific notes
- Not CARB approved. Destination and intended-use restrictions must be checked before sale.
- Emissions acknowledgement required before purchase.
