The Works Edition of SP Concepts' Big Bore 4.5 for Twin Cam baggers — the same 4.5-inch muffler platform, with the system pie-cut and purge TIG welded back together by hand at SP Concepts' Lake Elsinore, California factory.
FITMENT
SP Concepts publishes this system for 1996–2016 Harley-Davidson Twin Cam Touring (Bagger) models. We list it for the 2014–2016 Twin Cam Touring models we carry parts for: Road King, Street Glide, Street Glide Special, Electra Glide Ultra Classic, Ultra Limited, Ultra Limited Low, CVO Street Glide, CVO Limited and CVO Road King (2014–2016), plus Road Glide, Road Glide Special, Road Glide Ultra and CVO Road Glide (2015–2016 — Harley-Davidson did not build a 2014 Road Glide).
Not sure it fits your bike? Email info@norcalbaggersupply.com — email is the fastest way to reach us — and we'll confirm before you order. You can also call 916-626-9030 (Mon–Fri, 9 AM–5 PM PT).
CALIFORNIA NOTICE
Race use only — not legal for use in California. SP Concepts labels this system a “Competition Use Only / Race Ready” product. It does not conform to California Air Resources Board (CARB) standards, carries no CARB Executive Order, and does not contain a catalytic converter. It is not legal for use on pollution-controlled vehicles operated on public streets or highways in California, and we cannot ship it to a California address — orders shipping to California will be cancelled and refunded. Available for shipment to the other 49 states.
SPECIFICATIONS
Manufacturer: SP Concepts (Stainless Powered Concepts) — Lake Elsinore, California, USA
SP Concepts part number family: SPC-4-003-WE (each finish carries its own part number, shown on its variant)
System type: 2-into-1 full exhaust system
.065 stainless steel headers, stepped from 1¾″ to 1⅞″ to 2″ at the collector
Hand TIG welded; machined stainless steel header collars
18mm O2 bungs with 12mm adapters — allows stock or autotune sensors
Complete hardware kit included — everything needed to mount it up
4.5″ high-flow performance rolled cone muffler with a stepped baffle from 2¼″ to 2½″ — increases bottom to mid range torque and horsepower
Finish options: Stainless, Black ONYX, Platinum
Works Edition: precisely pie cut and purge TIG welded by hand at SP Concepts' Lake Elsinore, CA factory
INSTALLATION
Install using the included complete hardware kit. SP Concepts' official install video for their 2-into-1 exhaust systems — the video SP links from its own FAQ install guide — is embedded below.
QUESTIONS RIDERS ASK
What makes this a Works Edition? SP Concepts pie-cuts the system and purge TIG welds it back together by hand at their factory in Lake Elsinore, California — a meticulous, labor-intensive process they describe as producing a work of art in the end.
Which motors can this system handle? Per SP Concepts, it increases bottom to mid range torque and horsepower on all motors, and tuned properly it can accommodate 88″ to 143″ engines.
Can you ship this to California? No. This is a race-use-only part that does not conform to CARB standards, so we do not ship it to California — see the California Notice above. It is available to the other 49 states.
