Here you will find our Engine Selection.
Choosing the right engine for your new airplane can be challenging. The engine is a main focal point and is the “heart and soul” of an airplane. A lot of time can be spent figuring out which engine would suit your application best. Making a good, well informed decision will pay off in performance, reliability, value and peace of mind. Hopefully some of the following information will help you make the right choice.
Aerovate- Made in China. Very good quality, great running two stroke engines. Electronic auto advance ignition system. The 26cc is offered only at this time. A good value. Includes a 1 year Warranty.
Desert Aircraft (DA) - These engines are designed and assembled in the USA. Touted as championship grade competition engines. Machined crankcases with red anodized parts. These are very popular engines and make a complete range from a 50cc single to a 200cc opposed four cylinder. Includes a 3 year Warranty.
DLE Engines (DLE) - These are designed and manufactured in China. Probably one of the most prolific engine producers in China. Good quality and good performance at a relatively low cost. A good value. Engine range starts with the 20cc single up to the 222cc opposed four cylinder. Includes a 1 year Warranty.
RCS radials- Manufactured in Hungary. The best sounding most realistic engine you can possibly install into your scale aircraft. These are five cylinder four stroke gasoline powered electronic ignition radial engines. They have been making radial engines for model aircraft use since 1998. Available sizes include 150cc, 215cc, 250cc and 400cc. A two cycle oil mix is used. Built in collector ring exhaust. Excellent quality throughout. Includes a 2 year Warranty.
RCS/SV Engines- Made in China. Only offering the 26cc two stroke at this time. A good value for the money. Inexpensive, good quality. Electronic auto advance ignition. Includes a 2 year Warranty.
Rotomotor- Designed and manufactured in the Czech Republic. High end CNC machined engines include the new four stroke 35FS single and the 85FS opposed twin. Top notch quality. Excellent power and fuel economy. Rotomotor designed auto advance ignition system. Includes a 2 year Warranty.
Valach radials- Designed and manufactured in the Czech Republic. Four stroke gasoline. Electronic ignition. The 420cc is a five cylinder configuration and the 800cc is a seven cylinder. The largest radials manufactured for model aircraft use. Very high end quality. Includes a 2 year Warranty.
ZDZ Modelmotor - Designed and manufactured in the Czech Republic since 1997. These are high end Euro spec engines that use rotary disc valves instead of reeds for the induction system for most of their designs. An extensive array of two stroke engines include single, twin opposed, twin inline, opposed twin and opposed four cylinders ranging from 40cc up to 420cc. UAV grade engines include onboard starters and generators. The 420JSR is a starter equipped belt drive engine geared mainly for UAV applications. Includes the most extensive Warranty of any current manufacturer, 42 months on the engines and 36 months on the electronic auto advancing ignition systems.
There are certain things to consider when making your selection. Do you want a single or twin cylinder engine? Do you want a 2 stroke or a 4 stroke? Do you want a radial engine for your application? Will an inline engine work for you? How much power do you need? What engines offer the best value for your application?
Two Stroke- The simplest of all engines. These have the highest power to weight ratio. Inexpensive and fairly easy to manufacture. A very wide selection of engine manufacturers to choose from. Available with various types of induction, carburetor placements and cylinder configurations. The simplest induction is piston porting where the carburetor is simply bolted to the side of the cylinder opposite of the exhaust port. The piston skirt serves as the induction valve. The rear carbureted versions tend to run the best. These use either reed valves or a spinning rotary disc valve as in the ZDZ engines. Single cylinder, twin cylinder opposed, inline twin, inline triple and opposed four cylinder configurations are available. Auto advance electronic ignition systems are commonly used and require a separate power source.
Four Stroke- Much more complex and more expensive than a two stroke engine. Produces less HP per cc than a two stroke, but has more torque and can spin a larger prop, although at a lower RPM. They are very fuel efficient and are much quieter. There are a very limited number of manufacturers. Available in either single or opposed twin configurations as offered by Rotomotor. Five and seven cylinder radial configurations are offered by RCS or Valach. Four stroke engines require regular maintenance including valve adjustments. Four stroke engines are heavier and are usually better suited to scale applications or in applications where fuel economy and/or noise are an issue. They do have a much more pleasing sound than a two stroke engine. They have a thick exhaust residue typically because of the two cycle oil mixes required. Auto advance electronic ignition systems are commonly used and require a separate power source.
Easy to install, most typical is inverted with a wraparound pitts style muffler. They are cheaper, lighter in weight than a twin of the same displacement, typically have bit more vibration but make more power.
Opposed twins -
The only way to get cc’s when you get much above the 85cc displacement mark is to add more cylinders. Typically they run smoother because of offsetting power pulses, but make just a bit less power than a single of the same displacement (if below 85cc’s). The 100-111cc range is very popular for entry level IMAC and 33-35% airframes where as the 150/160/170cc range is good for 37.5%- 42% Advanced and Unlimited flying. The big ZDZ 210 is by far the best choice for power in the 200cc class for planes above 42%.
Inline Twins -
Narrow cowled warbirds such as Mustangs, Spifires and Mosquito’s can benefit from this arrangement. Starting at 80cc and going up to the massive ZDZ 210 inline, these engines run extremely smoothly due to their alternating firing order. Because of this they typically make a bit less power than their opposed twin cousins of the same displacement because they lack the synchronized power pulse as in an opposed twin. Running at twice the power pulses per revolution as a single or opposed twin, the sound is simply amazing. The rear cylinder on any inline twin will not overheat if properly baffled.
Opposed Quads- Again, need more cc’s? Add more cylinders. Two stacked opposed twins running as smoothly as an inline with offsetting power pulses firing twice per revolution make these engines very powerful and smooth. Starting at 200cc and going up to the big ZDZ 420cc JSR with belt drive reduction, these are some of the more complex two stroke engines. Fairly heavy with twice the number of carburetors and ignition systems these are not for your typical modeler. The sound and performance of these engines is second to none.
Break In- A proper break in is so very important! A thicker gas/oil mix ratio should be used, typically 32:1 which is 4 ounces of oil to one gallon of gasoline. A non-synthetic oil should be used to help facilitate the piston rings to conform to the cylinder walls. We highly recommend the Pennzoil Outdoor Air Cooled Two Cycle oil for break in. Needle valves should be set on the rich side and application of full throttle should be very limited especially during the first couple of gallons of fuel. Some engines require a 32:1 mix be used for the life of the engine and others may use 40:1 (3.2oz/gal) or a 50:1 (2.56oz/gal) mix after break in. Typically a full synthetic is preferred after a significant and proper break in to greatly reduce wear and reduce exhaust residue. Always refer to the engine manufacturers instruction manual for specific details.
Cooling - This has been a huge issue. The use of baffles to help direct airflow to the engine’s cylinders and the use of spoilers on exit air openings to help create the vacuum needed to extract all of the hot air generated is of utmost importance. The carburetor must not be subjected to direct hot engine air but at the same time not subjected to extreme turbulence that may affect mixture settings and subsequent lean running conditions. Keeping all of these components cooled by a properly engineered airflow will insure the engine AND exhaust system will give you the best performance, reliability and longevity.
Exhaust Systems - Bolt on mufflers will be the easiest , lightest and cheapest way to go. Unfortunately this is also the loudest way to go. The use of headers and mufflers, be it tuned pipes, canisters or silencers will give the best performance and sound, provided your airframe can accommodate them.
Props - The right prop is a must for your airframe, engine and exhaust combination, although very subjective based on how you think the plane should fly. Two bladed props are available in either wood or carbon fiber. Carbon fiber is much stiffer, retains its pitch better and will not flex as much as a wood prop. Costs can be significantly higher than that of a comparably sized wooden propeller. Two bladed props with a large diameter will provide more thrust than a three or four bladed design, but typically are very noisy. This is because the airflow over the airfoil section near the prop tip starts to detach as it approaches the speed of sound. This occurs when the prop tip speed starts to exceed Mach 0.92. A three bladed prop with a smaller diameter is the preferred solution to reduce tip speeds, but must use more pitch to provide the proper load and gain back some lost efficiency. The result is a faster airplane with reduced propeller braking especially on down line maneuvers and landing. Three bladed propellers are usually fabricated from carbon fiber. The nature of this integrated one piece construction makes them much safer. For most competition flying and as required by most fields with noise restrictions a three bladed prop is a must.