Zenoah aircraft engines are famous throughout the modeling world for their outstanding power and exceptional reliability. These same qualities can be found in their new G-231, 23cc marine engine as well.
It boasts approximately 20% more horsepower than its predecessors, the G-23 Marine and is simple to start and adjust. It shares the same overall mounting dimensions as the older version, as well, so upgrading is easy.

Displacement: 22.5cc
Bore: 1.3 in
Stroke: 1.1 in
Total Weight: 54 oz
RPM Range: 3,500 - 15,000
Mounting Dimensions: 142 x 105 x 181mm
HP: 2.2
Carb Type: WT603/WT644 or WT257

Displacement: 25.4 cc
Cylinders: 1
Total Weight: 59 oz

Carb Type: WT603 / WT644

Displacement: 25.4 cc
Cylinders: 1
Total Weight: 59 oz

Carb Type: WT257

Displacement: 29 cc
Cylinders: 1
Total Weight: 59 oz

Carb Type: WT257

Note: This is a conversion engine as Zenoah does not make a 29cc Marine engine and has had the needed modifications to make it suitable for marine use (piston relieved and exhaust timing adjusted). All parts are genuine Zenoah.

A few modifications really wake up the Zenoah bringing the rating up to 4.7hp for this stage 1 mod engine.

Mods include: Compression raised, intake timing adjusted, exhaust timing adjusted, 257 carb, piston turned down, custom cap, and decal.

A few modifications really wake up the Zenoah bringing the rating up to 5 hp for this stage 2 mod engine.

Mods include: Compression raised, intake timing adjusted, exhaust timing adjusted, 257 carb, piston turned down, lightened piston, custom cap, and decal.

The fully modified engine built for oval racing, use with a 2" band pipe or our steel pipe, rated at 6hp.We have been building engines for over 5 years and have set several speed records with our engines. The modifications include: Intake and exhaust duration adjusted, compression raised, transfer ports directed, extensive piston mods, crank and bearings trued, flywheel balanced, precision seals installed, modified 257 Walbro, stainless bolts, NGK plug, magneto properly spaced, and a custom cooling cap.

Note: The Stage 4 Zen is close to the Stage 3 but comes with a full circle crank (genuine Zenoah) and an adjustable ignition timing adaptor.

The fully modified engine built for maximum performance and reliability, use with a 2" band pipe, rated at 6.5+hp.We have been building engines for over 5 years and have set several speed records with our engines. The modifications include: trued crank, intake and exhaust duration adjusted, compression raised, transfer ports directed, extensive piston mods, crank and bearings trued, flywheel balanced, precision seals installed, modified 257 Walbro, stainless bolts, NGK plug, magneto properly spaced, and topped with a custom cooling cap.