Ultimate Racing M3S nitro engine

ultimate M3S engine 640x382 Ultimate Racing M3S nitro engine

See: Modelix Racing

Modelix Racing have introduced the last addition to the Ultimate Racing range of engines, the new M3S engine. The Ultimate M3S is made by the prestigious Japanese O.S. brand and it’s the result of many hours of tests looking for the best configuration using components from different O.S. engines. The M3S is a long stroke, high torque and extreme power engine with low fuel consumption. This is the most powerful engine from the Ultimate range of engines and it is perfect for both buggy and truggy.

Cooling head

The cooling head has been redesigned by Modelix. It’s not as low as the B2102 lower profile but it’s lighter so it keeps the center of gravity as low as the B2102 but improving its performance on very high temperatures. It’s the same head as the M3T engine.


The Ultimate M3S engine comes with a new carburetor where high speed needle holder has been redesigned for a better refrigeration of the fuel flow into the carburetor, lowering the temp of the carb, and as a consequence it’s more stable with a great idle stability, improves fuel mileage and overall engine performace. Besides this, the uniball joint of the carb slide has also been modified with two stoppers instead of one. With this new modified design, you can easier adjust the angle of the uniball joint without having to disassemble the engine. This carb offers a higher accuracy tuning, a very interesting advantage to experienced drivers.


The backplate is CNC machined and made of 7075-T6 Swiss Aluminum. The reason of making it with this material is to make it harder than the original and reduce the conrod-backplate friction increasing the life of the conrod and improving engine efficiency and performance. Thanks to its design, you can remove the backplate without damaging the conrod even when it is on its lower position (PMI). The lateral grooves allow to easily remove the backplate without having to use any tool that can damage it.


The M3S crankshaft has been designed by the O.S team of engineers to ensure an optimum flow of fuel thanks to the aerodynamic design and the silicone filling. It is balanced with a tungsten weight in order to increase the inertia to rotation. Crankshaft durability has been improved thanks to the Dimond-Like Carbon (DLC) coatings.


In line with the high quality and performance of this engine, its two high precision ceramic made in Japan bearings ensure high idle stability, longer life and low friction at high temperatures.


The engine is supplied with two venturis, a 6.0 and a 6.5 to adjust fuel mileage and torque.

Sleeve and piston

The sleeve with 3 inlet port and an exhaust port guarantee a low fuel consumption with a very high but smooth and linear power. Both, the sleeve and piston are made from a high strength aluminium bar to improve its durability.

(adsbygoogle = window.adsbygoogle || []).push({});

Technical specifications

  • Displacement: 3,46 cc
  • Power Output: 2.75 PS/2.71 hp @ 34.000rpm
  • Practical Range RPM: 4.000-44.000
  • Bore x Stroke: 16,27×16,80
  • Sleeve: 3 + 1 ports
  • Rear Ball Bearing: ceramic
  • Front Ball Bearing: ceramic
  • Crankshaft: 14 mm
  • Carburetor: Aluminum w/ insulator gasket
  • Glow plug: P3 Turbo
  • Exhaust Position: rear
  • Weight: 345g
  • Fuel type: 25% nitro. Recommended fuel Nitrolux.

VRC 468x90 Ultimate Racing M3S nitro engine

Leave a Reply