Marine Engines

Billet delrin version is now available and is half the weight of the aluminum version. OBR power stack is compatible with most aftermarket clamp on air filters. This is a bolt on performance item that will improve power on any engine that's stock or fully modified. We spent several months developing this stack on our in-house flow bench and dyno. We've seen more power out of this design than any other stack that we have tested. Dyno graph can be found in the images. Tapered bore increases velocity through the intake tract and gives better consistency. The clamping surface has barbs to prevent the air filters from falling off under hard running. There is no boss on this stack which allows the air filter to be pushed closer to the carb for cars that have minimal air filter clearance.

Fully ported 30.5cc reed engine. Comes complete as shown in the picture with a Zenoah EZ start. Engine mounts and carb not included.

45" cat

The following work has been done:

disassemble crank to install +5mm long rod and re-balance combustion chamber cut to accommodate +2mm stroke crank and dome re-cut.

5mm cylinder spacer used to compensate longer connecting rod

eyebrows

transfer runner knife edged transfer ports enlarged/reshaped

intake port epoxied with dual boost ports cut lightened and windowed piston

exhaust duration raised and port widened

ignition timing advanced through coil location on ignition plate (fixed)

reed valve flowed and surfaced

reed case intake track flowed and surfaced

Fully ported 30.5cc reed engine. Comes complete as shown in the picture with a Zenoah EZ start. Engine mounts and carb not included.

The following work has been done:
combustion chamber cut to accommodate +2mm stroke crank and dome re-cut
eyebrows
transfer runner knife edged
transfer ports enlarged/reshaped
intake port epoxied with dual boost ports cut
lightened and windowed piston
exhaust duration raised and port widened
ignition timing advanced through coil location on ignition plate (fixed)
reed valve flowed and surfaced
reed case intake track flowed and surfaced

Complete marine reed case with bearings and seals. A CY marine flywheel and coil must be used. The starter pawls need to be machined on a CY flywheel to accept a Zenoah EZ start.

Marine conversion for our G290 based reed cases. This ignition plate can be swapped with the air cooled fan cover to convert our G290 based reed engines. Kit comes with ignition plate, hardware, coil spacers and engine mount spacers. A CY marine flywheel and coil must be used. The starter pawls needs to be machined on a CY flywheel to accept a Zenoah EZ start.