Digital Restoration

O.S. ENGINES OS-MAX-21VG-PES

Welcome to a tour through the results of the digital restoration of this 3.46 cc glow plug engine for RC cars.


The OS-MAX-21VG-PES was the second model engine I digitally imported into CAD, after a Webra Speed. This was all part of digitizing the Carson King of Dirt 4WD racing buggy, but more importantly, it served as further practical design training for my PTC Creo, or rather, back then, Wildfire 4.0 design program. I started the design at the end of 2010, and after a few weeks, the essential components were complete. But not entirely... not in the CADDICTED style... until now.


Regarding the engine:

The OS MAX-21VG series engines are 3.46 cc high-performance engines specifically designed for racing 1:8 scale radio-controlled model cars. Their design takes into account the demanding requirements of the world's most experienced drivers. An extensive research, development, and prototyping program has resulted in the creation of the most powerful production racing car model engines.


The variant with Rotostart clutch for electric starters with starter shaft was digitally restored.

Other engines

Displacement            3.46 cm³ (0,211 cu.in)

Bore                            16.60 mm

Stroke                         16.00 mm

Speed                   ​​      3,000…36,000 1/min

Power                         2.00 PS / 1.471 kW @ 30,000 1/min

Crankshaft thread    ¼" - 28 UNF

Combustion type      2-stroke

Fuel                             methanol, oil, nitromethane



CAD-models               28.11.2010 - 16.11.2025

Rendering                   07.11.2025 - 16.11.2025

Blueprint                     09.11.2025 - 22.11.2025

Step-model                 _2747_os-max-21vg-pes.stp

Engine purchase        ~2007

Production date         approx. 2006