O.S. Speed B21 AD3 Adam Drake 3 Competition .21 Nitro Engine w/2100SC Pipe

🔥 O.S. Speed B21 AD3 Adam Drake 3 Competition .21 Nitro Engine Combo

The O.S. Speed B21 AD3 Adam Drake 3 Competition .21 Nitro Engine is the latest evolution in the legendary B21 lineup — precision-tuned in collaboration with Adam Drake himself. This powerplant delivers incredible throttle response, a refined linear power band, and improved fuel mileage, all while maintaining the smooth drivability top racers demand.

The AD3 features a re-engineered crankcase for seamless low-to-high speed transitions, a backplate with a steel insert for reduced friction, and an updated cooling head that’s 3mm lower and 14g lighter to lower the center of gravity. Combined with the included 2100SC pipe and 75mm manifold, this combo offers unmatched balance of torque, efficiency, and race-ready response for 1/8 buggies and trucks.

⚙️ Key Features

• Designed with Adam Drake: Custom-tuned specs exclusive to the AD3 edition for pro-level performance.
• Race-Optimized Combo: Includes 2100SC pipe and 75mm manifold for maximum flow and throttle response.
• Lightweight Cooling Head: 3mm shorter, 14g lighter — lowers CG and improves handling balance.
• Steel-Lined Backplate: Reduces friction and boosts both power output and fuel economy.
• Updated Crankcase Design: Smoother, more linear transition across the full RPM range.
• Exclusive Cylinder Liner & Porting: Refined for torque and throttle feel unique to the AD3.
• DLC Crankshaft: Dual tungsten counterweights for stability and torque at high RPMs.
• Semi-Long Stroke Layout: Delivers superior low-end torque with extended top-end power.
• Ceramic Rear Bearing: Reduces drag and heat buildup during long main events.
• 21J Carburetor with Reducers: Includes blue anodized 6.5mm and 7.0mm inserts for tuning flexibility.
• O.S. Speed P3 Gold Plug: Optimized for smooth low-speed torque and clean throttle pickup.

📋 Specifications

• Bore: 16.4mm (0.646")
• Stroke: 16.55mm (0.652")
• Displacement: 3.49cc (0.213 cu.in.)
• Configuration: Single Cylinder
• Power Type: Glow (Nitro)
• Horsepower: 2.61 HP @ 34,000 RPM
• RPM Range: 4,000 – 42,000 RPM
• Engine Weight (Only): 350g (12.35oz)

📦 Includes

• (1) O.S. Speed B21 AD3 Adam Drake 3 Engine
• (1) 2100SC Pipe & 75mm Manifold
• (1) Engine-to-Header Gasket
• (1) O.S. Speed P3 Gold Plug
• (1) 21J Carburetor
• (2) Blue Anodized Carburetor Reducers (6.5mm & 7.0mm)

Engineered for precision, tuned by legends — CX Factory delivers elite-grade performance parts trusted by serious racers around the world.