Applications
Built for One System. Coming for Every Shifter.
ShiftMass™ is a modular weight and head platform. One base, one ring set, any head — tuned for your car. We launched with the most-requested Subaru and Toyota fitments, and we're expanding from there.
Shipping Now — Subaru & Toyota Sport Compacts
Standard Lockout and Large Lockout Complete Systems are live. Multiple head profiles, eight weight settings each, and proper fitment for the factory reverse lockout — no thread adapters, no universal parts.
Standard Lockout fits:
- Subaru WRX 2015–2025 (6MT)
- Subaru STI 2004–2022
- Subaru BRZ 2013–2021 (Gen 1)
- Scion FR-S 2013–2016
- Toyota 86 / GT86 2013–2021
- Subaru Legacy GT Spec.B 2006–2012
- Subaru Forester XT 6MT 2014–2018
Large Lockout fits:
- Subaru BRZ 2022+ (Gen 2)
- Toyota GR86 2022+
Next Up — Direct-Thread Base
For manual transmissions without a factory reverse lockout collar. Same head system, same brass weight rings — a different base, cut and threaded for your car's pitch, no lockout cavity. Not an adapter. Not a universal part. A base machined for the thread you actually have.
Thread pitches in this round:
M10x1.25 • M10x1.5 • M12x1.25 • M12x1.5 • 3/8-16
Good fits include:
- Classic American — Corvette, Camaro, pre-2005 Mustang (3/8-16)
- Older Subaru 5MT — WRX, Impreza, Forester, Legacy
- Honda — S2000, Civic (non-Si/Type R), Integra, RSX
- Classic Japanese — Miata NA/NB/NC, 350Z, 370Z, MR2, Supra
Also In Development
Ford Mustang 2015+ • Focus ST • Focus RS • Fiesta ST • Toyota GR Corolla • GR Yaris • Shelby GT350
Don't See Your Car?
Manual transmissions come in a lot of thread pitches and shifter designs. If yours isn't listed, tell us what you drive. Email zach@shiftmass.com with year, make, and model. We keep a research list, and the right signal moves things forward.
Hear It First
Drop your email in the signup at the bottom of the page. New fitments, new head designs, new materials, anything else in development. No spam. One email per release.
A Different Philosophy
Most knobs lock form and function together. You pick a shape, and the weight comes with it. Want a different feel? Buy a different knob.
ShiftMass separates them. The head is form — shape, material, finish. The weight stack is function — how the shifter loads, settles, and returns. Change one without giving up the other.
The goal is simple: give drivers the balance that suits their transmission and their style. Your car, your hand, your throw. Dial it in and leave it, or keep changing it. The base stays in the car either way.
ShiftMass isn't a generic weighted knob. Every product we ship is engineered for the specific factory shifter it fits — correct thread pitch, correct lockout fitment, correct gate pattern, correct feel. No thread adapters. No universal parts. We'd rather be late than ship something that doesn't work right.
One base. One ring set. Any head. Your feel, your car, your range.