Specifications:

Displacement: 3,49 cc
R.P.M. (max power): 41.800 RPM
Bore x stroke: 15,88x17,60 mm
Sleeve: 9 ports
Rear ball bearings: steel
Front ball bearings: steel
Crankshaft: 14,5 mm - turbo - tuned - DLC
Carburetor: aluminium - 9 mm - slide 3 adj.
Glowplug: Turbo (CT8)
Exhaust position: rear
Starting: standard
Weight: 341 g
Fuel type: 16% nitro

Conrod:
New R4/18 conrod, redesigned and made with a special aluminum alloy that allows it to have a high resistance while maintaining the lightness and performance of the previous R4/17.

Crankshaft:
The crankshaft is grinded to increase the mixture flow and has a special shape to reduce turbulences inside the crankcase. The balancing is done by three inserts made of tungsten alloy and the inlet has a silicon filling to reduce the weight of the crankshaft to improve acceleration. The durability has been significantly improved with the DLC coating.

New compact carburettor:
The new three tuning needles gives a better idle and improves the ability of the engine to return to low rpm after throttling.

Sleeve:
The sleeve has 9 transfer ports and an exhaust with booster ports. The special shape and positioning of the ports improve the internal fluid-dynamics to obtain the maximum possible performance.

Underhead:
The underhead designed to work with a mixture of 16% nitromethane (code 28038), but optionally the engine can be supplied with a underhead to operate at 25% (code 28025).

Exhaust:
Improved internal machining of the crankcase drainage port to facilitate the expulsion of fumes.

Cooling head:
New head, redesigned to improve the flow of air and thus increase cooling and ensuring an optimal center of gravity.

Recommendations (NOT INCLUDED):

Pipes:
(NOT INCLUDED) 51010 Tuned Pipe (EFRA 2015) 3 chamber polished tuned pipe, more progressive with lower fuel consumption

Manifolds:
(NOT INCLUDED) 41015 Manifold Shorter exhaust gives less acceleration, but an increased topspeed

(NOT INCLUDED) 41016 Manifold Medium exhaust is half way between short and long, generally used as a starting setup

(NOT INCLUDED) 41017 Manifold Longer exhaust gives more acceleration, but reduced top speed