AD3

O.S. SPEED and Adam Drake have collaborated once again to bring you the New Adam Drake B21(AD3) edition engine. Adam Drake is a multi 1/8th Scale ROAR National Champion who is famous for his extensive knowledge of Nitro racing engines that spans over 25 years. The O.S. Speed B21AD3 engine has several updates from champion Adam Drake. Based off the B21AD2, the new features of the AD3 include a boost bypass processing for the crankcase that increases throttle response, helps the engine run smoother and makes it easier to drive. The new AD3 signature cooling head is anodized black and has blue outer rings that compliments Adam’s unique style.

The AD3 cooling head is 14g lighter and lower profile to help lower the center of gravity and improve driving performance. The inner head uses a new black O-ring to reduce vibration and improve dust resistance. The new backplate has a built-in thrust plate to reduce friction between the connecting rod and the backplate making the engine more durable and will increase engine life. The AD3 comes with two different carburetor restrictors, 6.5mm for Buggy and 7.5mm for Truggy.

You can purchase the AD3 as engine only or the AD3 engine combo set. The AD3 combo comes with TB02 pipe(2090SC) and 75mm manifold. It’s an excellent choice for both buggy and truggy racing as it provides a linear power band, exceptional fuel mileage and tons of overall power.

Available with and without Break-in service (EBIS) through www.thedrakeracing.com and selected retailers.

Features:
Adam Drake’s unique cylinder design that’s exclusive to the Drake edition engines only.
Redesigned cylinder liner with optimized porting.
DLC coated crankshaft with larger double tungsten counterweights.
A unique semi-long stroke configuration.
6.5mm and 7.5mm blue anodized aluminum carburetor reducers.
Front steel bearing and Ceramic rear bearing.
21J carburetor.
These features will provide responsive low-end power and more overall torque.

Specifications:
Displacement： 3.49cc / 0.213 cu.in.
Bore: 16.4mm / 0.646 in.
Stroke: 16.55mm / 0.652 in.
Output 2.65 ps / 2.61 hp / 34,000 r.p.m.
Practical RPM range: 4,000-42,000 r.p.m.
Engine Weight: 350g / 12.35oz

Recommended Pipe and Header for the AD3 engine:

The TB02/2090SC pipe and 75mm manifold is the first choice option for the AD3. (Recommended for Buggy.)

The TB02/2090SC pipe and 85mm manifold is also a nice option for the AD3. (Recommended for Truggy.)

The AD3 Engine Combo set comes standard with TB02/2090SC pipe and a 75mm Manifold.

When running on lower grip conditions or if you prefer a little smoother initial power, we recommend the TB03 pipe set.

Drake Carb Settings:

High Speed Needle: 1.30mm – 1.45mm in from flush.
Low Speed Needle: 0.45mm – 0.6mm in from flush.
Mid Speed Needle: flush to 0.15mm in from flush.