O.S. Speed 21XZ-B Spec II "Tuned" Off-Road Competition Buggy Engine

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O.S. Speed 21XZ-B Spec II "Tuned" Off-Road Competition Buggy Engine
Price: $449.99
Discontinued Online
This item is discontinued and no longer available for purchase. You may want to search our site for a similar item.
This is the O.S. Speed 21XZ-B Spec II Tuned Off-Road Competition Buggy Engine. Since their inception, drivers around the world have equipped their vehicles with O.S. Speed engines because they demand a race-winning performance edge. The 21XZ-B Speed Spec II has been factory tuned for maximum performance, with modifications that make this power plant leaner and meaner than any XZ-B model ever produced. The Speed Spec II is engineered to deliver next level performance, and is guaranteed to give you the power you need to make it to the top of the podium.

Features:
  • Lighter DLC coated, tungsten slugged and silicone ramped crankshaft
  • Modified piston and con rod that reduces overall weight
  • Redesigned cooling head with V-shaped fins for lower CG and efficient cooling
  • 21J carburetor for smoother acceleration and better fuel mileage
  • A 6.5mm venturi is installed; 6mm and 7mm venturi's are included
Specifications:
Displacement:
0.213 cu in (3.49 cc)
Bore: 0.641 in (16.27 mm)
Stroke: 0.661 in (16.8 mm)
Practical RPM Range: 4,000-42,000
Output: 2.65 ps @ 34,000 rpm
Weight: 12.52 oz (355 g)

Includes:
  • 21XZ-B Speed Spec II Buggy Engine w/21J carburetor
  • P3 Turbo Glow Plug
  • Exhaust Seal Ring
  • 6mm, 6.5mm and 7mm Venturi's
  • (2) Dust Caps
  • Instruction Manual

This product was added to our catalog on May 16, 2013

Charles Mims
Wednesday, Jun 4 2014 (about 9 years ago)
O.S. Speed 21XZ-B Spec II "Tuned" Off-Road Competition Buggy Engine
This ENGINE IS awesome, what a power plant.
I have 3 gallons through this engine. It is unbelievable .
I have the 2060 pipe combo and this mill
Will idle all day!!!! SMOOTH POWER Throughout the power band.
Once again thanks OS for a reliable engine you can count on @race day.
Anonymous
Sunday, Jun 2 2013 (about 10 years ago)
O.S. Speed 21XZ-B Spec II "Tuned" Off-Road Competition Buggy Engine
Fantastic engine when equiped with 2060 pipe. A little smoother than the previous version but still very strong and reliable. For me it´s #1.
Kah Chik Yong
Wednesday, May 15 2013 (about 10 years ago)
O.S. Speed 21XZ-B Spec II "Tuned" Off-Road Competition Buggy Engine
Awesome engine.. Use it with os pipe 2090. good range of power. easy to tune
Hezi Tzalah
Tuesday, May 5 2020 (about 3 years ago)
O.S. Speed 21XZ-B Spec II "Tuned" Off-Road Competition Buggy Engine
i want to buy this iteam................................
peter micevski
Tuesday, Aug 4 2015 (about 8 years ago)
O.S. Speed 21XZ-B Spec II "Tuned" Off-Road Competition Buggy Engine
This engine is a 3 Port Power plant..I run this engine in a Kyosho GT2,and race regularly.Plenty of power with the 2060 pipe,and Novarossi 41032 manifold.Easy to tune and idles all day with OS RP7 glow plug on 25% nitro fuel.
tj saunders
Wednesday, Jul 1 2015 (about 8 years ago)
O.S. Speed 21XZ-B Spec II "Tuned" Off-Road Competition Buggy Engine
OS Engines lives up to their rep with this engine, I run it in my truggy with the 2090 pipe and have had the best performing engine ever, highly recommended.
Alonso Diez Canseco
Wednesday, Jun 17 2015 (about 8 years ago)
O.S. Speed 21XZ-B Spec II "Tuned" Off-Road Competition Buggy Engine
How many ports does this engine has?.Can sombody tell me?.