The O.S. Speed B21 AD3 Adam Drake 3 Competition .21 Nitro Engine with 2100SC Pipe is the latest evolution of this potent racing engine. Designed in collaboration with the legendary Adam Drake this AD3 edition features several updates and improvements over the already competitive B21 engine platform. The AD3 uses an updated crankcase inner design for linear power making the transition from low to middle to high speeds almost seamless. Adding to this is an updated backplate with a steel lining reducing resistance and aiding in not only extra power but better fuel mileage. Helping to keep weight in check a freshly designed cooling head features a 3mm lower height and is 14g lighter overall lowering the engine's center of gravity and shedding weight in a critical area. This combo includes a 2100SC Pipe and 75mm manifold recommended for buggy racing applications.

Plus, these engines have been broken in by Adam himself using Adam's "EBIS" engine break in services! Now, the same "Oil Bath" break in service trusted by Ty Tessmann, Ryan Maifield, Robert Battle, Spencer Rivkin, Mike Truhe, and many others is now available to you, performed with the knowledge and precision that has made The Drake a legend in RC racing.

Featuring a semi-long stroke configuration, this engine boasts a DLC crankshaft with larger double tungsten counterweights and a unique cylinder design that’s exclusive to the Drake edition engines. These changes will provide smoother low end power and more overall torque than the previous model. The AD3 is an excellent choice for both buggy and truck racing as it provides a linear power band, exceptional fuel mileage and tons of overall power.

Adam Drake Engine Break-In Service (EBIS)

Features:

Adam Drake’s unique engine specs not used on any other O.S. Speed engine
Engine/pipe combo recommended for buggy racing
Updated cooling head; 3mm lower height for low gravity and 14g lighter. Black/blue double anodized head.
Back plate with steel lining like B2104 for friction resistance
Updated crankcase inner design for linear power transition from low–middle–high speed
Redesigned cylinder liner with optimized porting
DLC crankshaft with larger double tungsten counterweight
Semi-long stroke configuration
Blue anodized 6.5 and 7.0 mm carburetor reducers
Ceramic rear bearing
21J carburetor
O.S.SPEED P3 gold plug, great for medium and low speed torque performance, is also included

Specifications:

Bore: 16.4mm / 0.646 in.

Cylinders: Single

Displacement: 3.49cc / 0.213 cu.in.

Engine (Only) Weight: 350g / 12.35oz

Power Type: Glow

Horsepower: 2.61 HP / 34,000 rpm

RPM Range: 4,000 - 42,000

Stroke: 16.55 mm / 0.652 in. output

Includes:

(1) AD3 Engine with Adam Drake Break-In
(1) 2100SC Pipe and 75mm manifold
(1) Engine to Header Gasket
(1) P3 Gold plug
(1) 21J carburetor
Blue anodized 6.5 and 7.0 mm carburetor reducers

O.S. T-2090SC One Piece Tuned Pipe w/Manifold (Welded Nipple) OSMG2953