ESP Mod/ ESP CHAMPIONSHIP PORTED GP290 36mm kit +2MM - cc253


2 in stock

It’s now here, due to popular demand! ESP Now does both the modification AND porting work on these kits!

If displacement is what you crave, look no further. This ESP modified & ESP Race Ported big-bore combo kit will allow you to convert your current engine into a 30.5cc performance monster. Feel the power that only a larger engine can provide. This kit is a TORQUE MONSTER, with killer low end and midrange power. ESP modifies this cylinder by machining at the head. The stock 36mm cylinder does not have room for the longer crankshaft in this kit, 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 and the piston ring remains in the well-plated area of the cylinder. 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 effiecient burning. These ESP modified cylinders are then race ported by ESP – intake, exhaust, and transfer ports have been enlarged/reshaped for more fuel/air flow and hence more power. Kit includes ESP modified + ESP ported 36mm cylinder, 36mm piston, piston ring, piston pin and two pin washers, circlips, two cylinder bolts, insulator gasket, and CMR7H spark plug. Increases your engine displacement to 30.5cc (36mm bore) when used with a 30mm stroke crankshaft. This kit is not recommended for use with a 28mm or 29mm stroke crankshaft, as the modifications are specially tailored to work with a 30mm stroke. Increases engine power SUBSTANTIALLY – estimated engine power output is 4.3+ HP. This high-performance product requires 91 octane (using the R+M/2 octane rating method) or higher fuel, and comes without warranty. Fits Zenoah G23LH / G230RC / G260RC engines when a +2mm (30mm total stroke) crankshaft is added. Also fits Chung Yang CY23RC / CY26RC / CY27RC / GP290 engines when a +2mm (30mm total stroke) crankshaft is added. Bolts directly on to Chung Yang CY29RC engines, as this engine features a 30mm stroke crankshaft as stock. Bottom line – to install this kit on any engine except a CY29RC, you must purchase a +2mm crankshaft. For Scooters: Fits any scooter using one of the above engines. Fits 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, and Pajero. Also fits Smartech Traveler, Firehammer, XTM, Carson Attack, HPI Baja 5b, and other large scale RC cars. Must be used together with a 30mm stroke crankshaft. 

Note: Installing the crankshaft involves splitting the cases. The crankcase gasket can be re-used if in good shape, but will often need replacing (it is our part # dd252). Also, check your crankcase seals (part dd262), as they sometimes need replacing as well. The crankcase bearings are usually fine to be re-used but it is wise to check them before installation.