This custom-built CY31RC engine, available exclusively at DDM, offers simply amazing performance. 30.5cc's of modified and fully ported power. 36mm bore, 30mm stroke. Simply put, this engine is the "king of kings" - it will out-torque and out-rev any other piston port 30.5cc motor. Aprox 4.5+ horsepower, and 6+ horsepower with a tuned pipe. Available in black or chrome, and with or without inner clutch. DDM has taken the hassle out of getting a massive 30.5cc motor - we've custom built them for you. The engine comes fully assembled and ready to bolt-on.
So where does the power come from? We start with a Chung Yang stuffed crank CY29RC engine (35mm bore, 30mm stroke - 28.9cc). The 35mm top-end is removed and set aside. We want a larger, 36mm top-end for increased displacement and power! But the stock 36mm cylinder does not have room for the long 30mm stuffed crankshaft, so ESP has machined out the proper spacing. This is a more efficient and reliable solution than stacking gaskets to achieve the needed space, as there is proper spark plug clearance, the piston ring remains in the well-plated area of the cylinder, and the ignition coil remains properly gapped to the flywheel. The squish band is cut so there will be .020"-.025" of squish (using the stock .020" cylinder gasket), and the combustion chamber is machined to get the compression ratio down to 14:1 for running on premium pump 91 or higher octane gasoline. The head geometry is reshaped to the proven standard 'hemisphere' shaped combustion chamber, and the squish area equals 50% bore area, for more efficient burning.
After the cylinder spacing modifications are complete, ESP then fully ports the engine. ESP completely tears down the engine and spends hours, cutting in great detail, the porting that will have you grinning from ear to ear. Detail like this is almost impossible to do on a milling machine - even a CNC milling machine.
Compare this to other offerings on the market and you will quickly see that DDM and ESP put power in your trigger finger without putting a huge dent in your wallet. Portwork includes:
1) Cylinder precision ported (exhaust, intake, and transfers enlarged and reshaped).
2) Polished exhaust port (for smooth flow and low carbon build up) and superb rough finish on the intake, cases, and transfer tunnels for better gas/air mixing.
3) Resurfaced intake, exhaust, and spark plug gasket surface on cylinder to insure no leaks.
4) Perfectly matched cylinder transfer tunnels to cases and case gasket matched.
5) Case porting to insure better flow into the transfer tunnels.
6) Cylinder skirt work to aid flow into the transfer tunnels.
7) New gaskets and piston c-clips.
8) Easy to read carb tuning instructions to get the most reliable power from your engine.
9) E.S.P. logo etched into side of crankcase.
For Scooters: Fits Goped brand Sport, Liquimatic, Bigfoot, X-ped, Super X-ped, Super Bigfoot, Go-Quad, Super Go-Quad, Go-Quad 30, GSR26R, GSR29R, and Homebuilders Kit.
For R/C: Fits a wide variety of 1:5 and 1:6 R/C cars, planes, boats, and helicopters. Same mounting dimensions as Zenoah G230RC / G260RC. For cars - fits FG: Marder, Leopard, Monster Beetle, Monster Truck, Stadium Truck, Pajero, Evo, Sportline, etc. For cars - fits FG: Marder, Leopard, Monster Beetle, Monster Truck, Stadium Truck, Pajero, Sportsline, etc. Also fits Duratrax Firehammer, Firehammer MT, XTM Grizzly, Carson Attack, HPI Baja 5b, Traxxas Monster Buggy, MCD Rally, MCD Race Runner, MCD 4x4 Monster Truck, and most other large scale onroad and offroad RC cars.
ESP Modified & ESP Fully Ported 30.5cc CY31RC Engine 4.5+ HP