VIR-TUS.21 Offroad

Displacement: 3,49 cc    R.P.M. (max power): 37.200 RPM    Practical range: 6.000-40.500 R.P.M.    Bore x stroke: 15,88x17,60 mm    Sleeve: 7 ports    Rear ball bearings: steel    Front ball bearings: steel    Crankshaft: 14,5 mm - turbo    Carburetor: plastic - 9 mm - slide    Glowplug: Turbo (C6TGC)    Exhaust position: rear    Starting: -    Weight: 370 g    Fuel type: 25% nitro

Available in:
rear and front ceramic ball bearings (VIR-TUS.21 OFF/S) 
rear and front steel ball bearings (VIR-TUS.21 OFF/A).

FEATURES

Coolinghead: This a 'Lighter&Lower evolution 2' type of cooling head. It is drilled and milled out to reduce the mass of the coolinghead which sits high up in the car and thereby lowering the Center of Gravity of the engine/car. The use of 6 screws instead of 4 ensures a better sealing between sleeve, botton head and the crankcase.

Sleeve: The sleeve has 7 transfer ports and an exhaust with booster ports. The special shape and positioning of the ports, covered by a patent, improve the internal fluid-dynamics to obtain the maximum possible performance.

Crankshaft: The crankshaft has a special shape to reduce turbulences inside the crankcase. The front part was extended to improve the seal against fuel leaking.

Patented: The shifted carburetor grants a better mixture flow inside through the crankase's intake. This gives the engine an improved fuel efficiency and a better power curve.

Conrod: The R7 conrod is made from a superlight alluminium which has been checked ultrasonic. The specific form of the R7 creates little turbulence inside the engine while running.

Rear cover: The rear cover presents a round shape to optimize the filling and reducing the dead spaces. the steel plate is to reduce friction and to expand the lifespan of the conrod.

Rear ball bearing: The new ball bearing reduces the inertia of the rotating masses and increases the engine's scavenging. You can see both the ball bearing and the manufacturing process result in the picture. These novelties give an increased throttle response and a higer top speed.

Carburettor: The carburettor of this engine is made from plastic and in "reverse" style and has a sliding throttle valve. The new three tuning needles gives a better idle and improves the ability of the engine to return to low rpm after throttling.