This is the Novarossi PLUS 21-4BTTA TUNED 4 Port .21 Off Road Engine. The PLUS.21-4BTTA includes all the factory tricks and tweaks that are found on the PLUS 21-4BTT, but substitutes the ceramic rear bearing with a high quality steel bearing to provide you with a high quality "tuned" Novarossi engine at a significantly reduced price!
- Cooling Head: The 'Lighter & Lower evolution 2' type cooling head has been drilled and milled out to reduce the mass of the cooling head, reducing the Center of Gravity of both the engine and car.
- Compression Rings: The ignition timing is controlled with shims that vary in thickness. You can add or remove a shim to alter the ignition timing. The ignition timing is related to the percentage of Nitro in the fuel and the altitude (above sea level) of your model.
- Conrod: The R7 conrod is made from a super light aluminum which has been ultrasonically tested. The shape of the R7 rod reduces turbulence inside the engine while running.
- Sleeve: The sleeve has 4 transfer ports, the best compromise to make linear power with minimal fuel consumption.
- Rear Cover: The rear cover optimizes case volume and reduces dead space. The steel plate reduces friction and extends the lifespan of the conrod.
- Crankshaft: This engine has been "Factory Tuned". Novarossi has modified the crankshaft to futher improve the power output and driveability.
- Carburetor: The carburetor is made from plastic, in "reverse" style and has a sliding throttle valve.
- Glowplug: The glowplug of engine is a Turbo type glowplug. Turbo glowplugs have a different shape than Standard glowplugs and therefor are not interchange able with engines that are using Standard glowplugs!
Recommended Tuned Pipes: EFRA 9901, EFRA 9853
Recommended Tuned Manifolds: 41021, 41029, 41030
Max Power: 2.60 HP @ 35,500 RPM
Practical Range: 6,000 ~ 38,000 RPM
Bore x Stroke: 16.26mm x 16.80mm
Transfer Ports: 4
Ball Bearings Front: Steel
Ball Bearings Rear: Steel
Crankshaft Type: 14mm - TURBO SG
Carburetor Type: 9mm Slide
Glowplug Type: TURBO - C6TGC
Exhaust Position: Rear
Fuel Type: Advise; 25% Nitro