Every hobby has its jargon, and LEGO® racing is no exception. This glossary decodes the parts and mods vocabulary — grouped by the Speed Shop’s component families so you can jump to the bit you’re building — and ends by decoding the words we use around the site.
Aero & Bodywork
- Canard
- A small angled fin on the front corner of the car — a dive plane, borrowed from real aero kits.
- Diffuser
- The rear-lower slope assembly under the tail, common on Technic hypercars — cosmetic on a LEGO build.
- Splitter
- A flat lip under the nose that visually splits the air — wedge plates and tiles under the front.
- Gullwing / scissor doors
- Opening panels hinged to lift up (gullwing) or swing forward and up (scissor), as on the Sián and Daytona SP3.
Engine & Drivetrain
- Fake-motion engine
- A Technic engine whose pistons move as the wheels turn — cosmetic motion, not a real power source.
- Differential (diff)
- A geared unit that lets the driven wheels turn at different speeds through a corner; AWD flagships run one front and one rear.
- Forced induction
- A supercharger or turbo element — the exposed blower is the classic hot-rod look.
- Ackermann steering
- Steering geometry that turns the inner wheel more sharply than the outer, so both track the corner cleanly.
- HOG (hand-of-god)
- A knob or gear left exposed so you can steer or drive a function by hand — 'the hand of god' reaching in.
Wheels & Tires
- Staggered setup
- Running a narrower wheel and tire at the front than the rear — the classic hot-rod and drag stance.
- Integrated tire
- A single-piece wheel with the tire moulded on, rather than a separate rim and rubber tyre.
- Balloon tire
- A tall, fat tire with lots of sidewall — the 43.2 mm and 56 mm sizes on Technic supercars and off-roaders.
Cockpit & Safety
- Roll cage
- A bar-and-beam frame inside the cabin that protects the driver — common on rally and stunt builds.
Driver Gear
- HANS-style collar
- A neck-brace accessory over the shoulders behind the helmet, echoing motorsport's head-and-neck safety device.
Livery & Detail
- Livery
- The paint scheme and sponsor decals that identify a car — the defining Speed Champions detail layer.
Trackside & Pit Gear
- Light tree
- The start-line gantry of sequenced lights that counts a race down — a trackside staple.
Power & Electronics
- Powered Up
- LEGO's current motor system (2018+) — Technic hubs, angular motors and an app or Bluetooth remote.
- Power Functions
- The retired 2007–2020 motor system — M/L/XL motors, an IR receiver and battery boxes; still common secondhand.
Aftermarket
- RC conversion kit
- A third-party motor-and-battery kit that makes a static Technic build drivable by remote — clearly labelled aftermarket, never as an official LEGO product.
- Light kit
- A set-specific LED lighting kit with the wiring pre-planned for a model — headlights, tail lights and underglow. A third-party add-on, deep-linked to the maker.
Bricks & Octane, decoded
- Speed Shop
- Our parts, mods & gear hub at /speed-shop — every component family, from Aero & Bodywork to Wheels & Tires, in one place. We deep-link out to the makers; nothing is rehosted or sold here.
- Garage
- Your personal collection on Bricks & Octane — the sets and builds you own or have your eye on, kept in one showcase.
- The grid
- The community's shared stream of builds. “Put it on the grid” is our way of saying share your own — a race-day starting grid of everyone's cars.
- Paddock
- Where a featured build gets pulled out front for a closer look — our spotlight on a standout MOC, like the paddock behind the pit lane.
- Fair Play
- The LEGO Group's Fair Play guidelines, which we follow to the letter: LEGO® is only ever used as an adjective, we never show the LEGO logo or rehost anyone's instructions or images, and every build links back to its creator.
- Bay
- A vehicle category in the showroom — Sports & Supercars, Race Cars, Monster Trucks and the rest. (In the Speed Shop, parts are grouped into component families, not bays.)
- Pit Wall
- Our team's internal operator console for running the site — a behind-the-scenes tool, not a public section you can visit.
A note on the name
LEGO® is a trademark of the LEGO Group, which does not sponsor, authorize or endorse this site. Part lookups deep-link out to the catalogs; we rehost nothing.