Overview
Meet the 1/7 scale ARRMA LIMITLESS 120 8S, officially the fastest production spec ready-to-run RC car on the planet. This is not your casual weekend basher—this is the king of the speed demons, built for drivers who think 100 mph is just the warm-up lap. If you're searching for a high-performance brushless RC car UK that delivers genuine supercar-embarrassing speeds, the LIMITLESS 120 is your answer. Straight out of the box, this ready-to-run RC speed machine comes locked and loaded with everything you need to dominate asphalt, break speed records, and leave tyre marks on your memory.
Just drop in your choice of 6S or 8S hardcase LiPo battery and add a compatible charger, and you're holding the keys to the fastest production RC ever built. This latest LIMITLESS evolution doesn't just go fast—it gives you three different ways to send it, making it the ultimate choice for serious speed enthusiasts in the UK and beyond. The ARRMA LIMITLESS 120 doesn't just go fast; it goes ARRMA fast, with legendary build quality and performance that leaves other RCs in the dust.
With factory-assembled Spektrum electronics, a refined 3mm anodised aluminium chassis, and a tunable aero package that laughs at wind resistance, this is the serious choice for drivers who demand the absolute best in RC performance.
Key Features
- 120+ mph capable — Factory-assembled with an EXB centre differential and standard gearing delivers 70+ mph straight from the box for epic all-road chaos. Swap in the included high-speed pinion and reach 100+ mph like you're cruising to the shops. Install that high-speed pinion with the supplied centre spool and trimmed aero package for face-melting 120+ mph speed runs that'll make physics cry.
- Ready-to-run with Spektrum electronics — Unlike budget RC cars, the LIMITLESS 120 comes factory-equipped with high-quality Spektrum power ready to handle whatever voltage you throw at it. The IC5 connector-equipped Firma 160A Smart V2 ESC is paired with a Firma 1450Kv brushless motor complete with heatsink and dual cooling fans, ensuring reliability at extreme speeds.
- 6S or 8S LiPo compatibility — Run up to 8S hardcase LiPo batteries for maximum power and performance. This flexibility means you can start with 6S for learning and progression, then step up to 8S when you're ready to unleash the full fury and experience the absolute peak ARRMA speed potential.
- Completely waterproof construction — The motor, ESC, and Spektrum S665 digital steering servo are all waterproof because fast shouldn't mean fragile. You can bash this RC car in any conditions without worry—asphalt, short grass, loose gravel, or light rain won't stop this speed machine.
- Tunable aero package included — The factory-finished low-drag body comes with wing trim lines that let you dial back the downforce when you want maximum velocity. The full-width front splitter improves traction and handling, whilst the large rear diffuser reduces turbulence and drag at high speeds.
- Legendary ARRMA durability — The 3mm anodised aluminium chassis gets reinforced with a centre brace because structural integrity matters when you're breaking the sound barrier. Heavy-duty 4X4 transmission features EXB differentials with all-metal diff outdrives and gearbox internals that won't flinch when the throttle hits the floor.
- High-speed stability technology — A 34T Mod 1.0 spool combines with bearing-supported rear centre driveshaft to reduce drivetrain vibration. Stiff front springs and sway bar improve high-speed handling, whilst a wide rear track increases stability for predictable, controlled speed runs.
- Spektrum DX3 Smart transmitter with AVC — The included 2.4GHz radio keeps you in command with smart throttle limiting that lets you dial things back to 50% or 75% until you're ready for full speed. The 6-channel Spektrum SR6200A DSMR receiver comes loaded with Active Vehicle Control (AVC) technology that maintains traction and direction for enhanced stability.
- Professional-grade suspension — Big bore oil-filled shocks mounted on black-anodised aluminium towers keep the dBoots Hoons all-road tyres firmly planted for maximum traction on any surface. This suspension setup is engineered for the extreme forces generated at 120+ mph.
- Speed wheels and all-terrain tyres — Mounted on speed wheels with extra-durable hubs, the dBoots Hoons all-road tyres provide the grip and reliability needed for consistent high-speed performance across different road surfaces.
- Smart battery monitoring — The Spektrum DX3 transmitter features a Smart battery level indicator so you can follow exactly how much capacity is available before your run, preventing unexpected power loss during critical moments.
Technical Performance
The ARRMA LIMITLESS 120 8S represents the pinnacle of RC speed machine engineering. At 1/7 scale, this 5.28 kg brushless speed machine measures 730 mm in length, 312 mm in width, and stands 165 mm tall, making it a substantial and serious performer. The core of the machine is a refined 3mm anodised aluminium chassis reinforced with a centre brace, providing the structural rigidity necessary to handle the stresses of 120+ mph operation. The Spektrum Firma 4685 1450Kv brushless motor delivers raw power whilst the Firma 160A Smart V2 ESC rated for 6S and 8S LiPo batteries provides intelligent power management and thermal protection. With dual cooling fans and an aluminium heatsink, the motor stays cool even during sustained high-speed runs. The 4X4 drivetrain is optimised specifically for 8S power, featuring EXB differentials with all-metal diff outdrives and heavy-duty gearbox internals that refuse to flinch under extreme throttle inputs. A 46T spur gear combined with the 34T Mod 1.0 spool provides the gearing ratios needed for the three-stage speed progression. The Spektrum S665 waterproof metal gear digital steering servo delivers 277.75 oz-in of torque at 7.4V, providing responsive and precise steering control even at maximum velocity. A bearing-supported rear centre driveshaft reduces drivetrain vibration for smoother, more predictable handling. The suspension comprises big bore oil-filled shocks with stiff front springs, a sway bar, and a wide rear track that all work together to maintain grip and stability as speeds climb towards triple figures. The 15.95-inch (405 mm) wheelbase is optimised for stability. The dBoots Hoons all-road tyres mounted on speed wheels provide excellent grip across asphalt and light off-road surfaces. Measuring 7.08 x 2.76 x 2.16 inches (180 x 70 x 55 mm), the battery tray is large enough to accommodate bigger LiPo packs. This is a machine built for serious speed enthusiasts in the UK who demand genuine performance and reliability.
What's in the Box
- ARRMA LIMITLESS 120 8S BLX 4X4 Speed Machine RTR (fully assembled)
- Spektrum Firma 160A Smart V2 Waterproof ESC (6S/8S rated)
- Spektrum SR6200A DSMR 6-Channel AVC Surface Receiver
- Spektrum Firma 4685 1450Kv Brushless Motor
- ARRMA Heatsink and Dual Cooling Fans
- Spektrum S665 Waterproof Metal Gear Digital Steering Servo
- Spektrum DX3 Smart 3-Channel 2.4GHz Transmitter
- 4 x AA Batteries (for transmitter)
- Instruction Manual (multilingual)
- Miscellaneous assembly tools
- Exploded view diagram
What You Need to Complete
- 2 x 4S or 2 x 3S hardcase LiPo battery packs (alternatively, 8S hardcase LiPo for maximum performance)
- Compatible LiPo charger (AC mains-powered recommended for convenience)
- LiPo charging bag or safety sack for safe storage and charging
Frequently Asked Questions
- What is the top speed of the ARRMA LIMITLESS 120 8S? — The LIMITLESS 120 is capable of 120+ mph with the included high-speed pinion, optional centre spool, and trimmed aero package installed. With factory gearing and centre differential, you'll achieve 70+ mph immediately out of the box. With just the high-speed pinion installed, expect speeds over 100 mph. This makes it officially the fastest production spec ready-to-run RC car available.
- Is this suitable for beginners? — The LIMITLESS 120 is rated for Skill Level 5, indicating it is designed for experienced RC enthusiasts, not beginners. This is a high-performance speed machine that demands respect, precision driving skills, and understanding of LiPo battery management. Beginners should consider starting with an entry-level ready-to-run RC car UK before progressing to this level of performance machine. However, the included throttle limiting feature on the Spektrum DX3 transmitter allows you to limit speed to 50% or 75% as you develop your driving skills.
- What battery does the LIMITLESS 120 need? — The LIMITLESS 120 requires either 6S or 8S hardcase LiPo batteries. For 70+ mph all-road bashing from the factory setup, 2 x 3S or 2 x 4S LiPo packs wired in series will work well. For the full 120+ mph experience, you'll want two 4S hardcase LiPo packs (totalling 8S) to unleash maximum power. Spektrum Smart G2 LiPo batteries with IC5 connectors are the recommended choice.
- Is the motor and ESC waterproof? — Yes, both the Spektrum Firma 1450Kv brushless motor and Firma 160A Smart V2 ESC are completely waterproof, as is the Spektrum S665 steering servo. This means you can bash in wet conditions, on damp asphalt, or through light rain without worrying about water damage. However, check the instruction manual for detailed waterproof specifications and limitations.
- What is included in the radio system? — The LIMITLESS 120 comes with the Spektrum DX3 Smart 3-channel 2.4GHz transmitter and the Spektrum SR6200A DSMR 6-channel AVC receiver. The transmitter features throttle limiting (50% or 75%), Smart battery level monitoring, and the receiver includes Active Vehicle Control (AVC) technology for enhanced stability and traction management at high speeds.
- Can I use this for off-road bashing? — Absolutely. The LIMITLESS 120 features dBoots Hoons all-road tyres that provide excellent grip on asphalt, short grass, and loose gravel. This is not a purely road-only machine—it's designed for epic all-road chaos. However, it is primarily optimised for street speed running and should not be submerged in water or used in muddy conditions.
- What is the wheelbase and dimensions? — The LIMITLESS 120 has a wheelbase of 15.95 inches (405 mm), with an overall length of 28.74 inches (730 mm), width of 12.28 inches (312 mm), and height of 6.5 inches (165 mm). It weighs 5.28 kg (11.64 lb) without battery.
- How does this compare to other ARRMA models? — The LIMITLESS 120 is positioned as ARRMA's flagship speed machine. Unlike the ARRMA Infraction, which is a 1/7 4WD speed machine, the LIMITLESS 120 offers the ability to reach 120+ mph with the included optional gearing, making it officially the fastest production spec ready-to-run RC car on the market. It features Spektrum electronics throughout, waterproof construction, and a comprehensive tunable aero package not found on entry-level models.
- What is the warranty? — The ARRMA LIMITLESS 120 8S comes with a 2-year limited warranty covering manufacturing defects and faults. This warranty does not cover damage from crashes, water submersion beyond specification, misuse, or wear and tear from normal operation.
- Do I need to tune or service it before use? — The LIMITLESS 120 arrives fully factory-assembled and ready to run. You do not need to build, assemble, or perform pre-delivery inspection beyond checking for any visible shipping damage. Simply add a charged battery and transmitter batteries, then you're ready to drive. However, regular maintenance such as cleaning, bearing lubrication, and servo checks is recommended after frequent use.
Why Buy from RC Model Shop?
RC Model Shop is a trusted UK RC retailer and authorised dealer for all the brands we stock, including Traxxas, ARRMA, Losi, FTX, Hobbywing, Spektrum and more. Based in Walsall, we have a physical store where customers are welcome to come in, view products and purchase in store. Whether you are a seasoned competitor, a weekend basher, or just discovering the world of RC for the first time, our team of experienced RC enthusiasts is here to help you find the perfect setup and provide ongoing support. Order the ARRMA 1/7 LIMITLESS 120 8S AVC 4X4 RTR Street Speed, Red/Black C-ARA7816T1 today with confidence, knowing you are buying from an authorised retailer with genuine products, expert knowledge and a commitment to customer satisfaction. Shop online or visit us in Walsall — we look forward to helping you get the most out of your RC experience.
Parts Diagrams
Front Assembly 1
Front Assembly 2
Steering Assembly
Electronics Assembly
Tranmission Assrmbly
Chassis Assembly
Rear Assembly
Front & Rear Diff Assembly
Centre Diff Assembly
Centre Spool Assembly
Shock Absorber Assembly
Bodyshell
Rear Wing and Diffuser
