ORIGINAL: Mr Cajun Gator
To clear up my statement, yes the New G230RC does has 3/10 more hp than the CY 23.
For the RC Airboat I still stick to what I have said the CY is my engine of choice. My opinion is based on information, research from places that sell these engines.
Information from DDM
CY23RC 2.5 HP Engine - $149.00
Chung Yang CY23RC engine (32mm bore, 28mm stroke - 22.5cc) with Walbro WT-668 carb. 2.5 Horsepower. Similar design to the Zenoah G230RC - 4 transfer port 32mm cylinder, single ring piston, double sided finned flywheel, and HP exhaust canister. Ready to bolt-on. All parts are interchangeable with the Zenoah G230RC.
G230RC 2.8 HP Engine - $195.00
The brand-new 2005 Zenoah G230RC engine is a 22.5cc (32mm bore, 28mm stroke) performance machine. The engine features a stronger intake manifold for better thermal isolation, a red silicone spark plug cap, new blue gaskets, wider intake and exhaust ports, a lighter 32mm piston and thinner ring for reduced reciprocating mass, and improved transfer port matching between cases and cylinder. This engine offers serious performance. It features a 4 transfer port 32mm cylinder, Walbro WT-603 carburetor
CY27RC 3.25 HP Engine - $164.00
Chung Yang CY27RC engine (35mm bore, 28mm stroke - 26.9cc) with Walbro WT-668 carb. Includes 54mm inner clutch assembly pre-installed. Ready to bolt-on. 3.25 horsepower. Similar design to the Zenoah G230RC/G260RC - 4 transfer port hp cylinder, single ring piston, double sided finned flywheel, and hp exhaust canister.
G270RC 4-Bolt Engine w/Full ESP Porting 4+ HP - $439.00
The brand-new 2005 Zenoah G260RC engine is a 25.4cc (34mm bore, 28mm stroke) performance machine. The engine features a stronger intake manifold for better thermal isolation, a red silicone spark plug cap, new blue gaskets, wider intake and exhaust ports, a lighter 34mm piston and thinner ring for reduced reciprocating mass, and improved transfer port matching between cases and cylinder. This engine offers serious performance. It features a 4 transfer port 34mm cylinder, Walbro WT-603 carburetor
G260RC 3 HP Engine - $214.00
The brand-new 2005 Zenoah G260RC engine is a 25.4cc (34mm bore, 28mm stroke) performance machine. The engine features a stronger intake manifold for better thermal isolation, a red silicone spark plug cap, new blue gaskets, wider intake and exhaust ports, a lighter 34mm piston and thinner ring for reduced reciprocating mass, and improved transfer port matching between cases and cylinder. This engine offers serious performance. It features a 4 transfer port 34mm cylinder, Walbro WT-603 carburetor
The most recent testing I have done myself personally, was a speed comparison between a stock CY 27cc with the exception the carb was replaced by the walbro WT-813 and a CY29cc with the stuff crank and the walbro WT-813 carb.
Now I'm sure if you was to place each of these engines on a dyno the 29cc will show to have more hp than the 27cc.
The speed difference test was done on the same cajun gator rc airboat, same day, just a few minutes apart (5 minutes to change engines)
Result, top speed for the CY 29cc was 33.5mph top speed for the CY 27cc 36.6mph
Again as I stated the Zenoah is a very good engine.
Thanks for quoting the text I wrote on the website that I run
The reason the CY27RC gives you higher speed in your application is the shorter crank (CY27 is a 35mm bore, 28mm stroke setup - the CY29 is a 35mm bore, 30mm stroke setup). All else equal, a shorter crank will rev higher.
We've found the CY 35mm cylinders to be substantially less reliable than the other CY cylinders (36mm, 34mm, and 32mm). And all of the CY cylinders are less reliable than the Zenoah cylinders.
For a fixed-gearing application, where you want higher revs to get higher speed, a well ported Zenoah G260RC is an excellent choice. 28mm crank and good porting for high revs, while 34mm bore provides decent torque.