This engine now comes with a TR/OBR billet crankcase at no extra cost.Every long block or engine is now CNC ported and hand finished. CNC porting and hand finishing is all done in-house by the OBR staff. We do not contract out any of our porting so every engine is modified to our exact specifications. We are able to offer higher accuracy this way as well as more power. Our CNC machine has allowed us to take our porting to the next level due to us being able to do cylinder work that is not possible to do by hand.

The full mod 30.5cc has proven to be one of the most popular engines we build. With the higher reliability of the 4 bolt Zenoah engines we were able to achieve more power with out sacrificing reliability. We put all of the knowledge that we have picked up from years of dyno and field testing and came up with a monster. To start we completely tear down the engines and perform the following modifications:

1. Machine combustion chamber for a proper squish clearance without stacking cylinder gaskets
2. Reshape piston 
3. Lighten piston 
4. Relieve piston to prevent seizes 
5. Modify intake port for better flow 
6. Adjust intake duration to our specs 
7. Resurface all ports 
8. Modify transfer ports for better flow 
9. Enlarge and reshape exhaust port 
10. Adjust exhaust duration to our specs 
11. Remove stock crank and install 2mm stroker crank 
12. Install all new gaskets and c-clips when engine is assembled 
13. Re-bevel all porting and stock bevels to prevent damage to the piston and/or cylinder

This engine fits:
* Tech Note: Installation in an HPI Baja requires that the stock Zenoah clutch be modified for a direct bolt up. Or the clutch from your stock fuelie 23/26 can be installed on this engine for a direct bolt up. The last option is a TR/OBR sealed clutch housing. The sealed clutch housing can be used with a machined CY clutch plate for a direct bolt up.

Off-road Rc Cars: HPI Baja 5B/5T/5SC, MCD, Rampage, FG Marder, FG Marder Race, FG Monster Beetle, FG Monster Beetle Pro,FG MT5,FG Stadium Truck, Duratrax Firehammer, Carson Attack, Smartech Traveller,FG Leopard, XTM, Leopard Race, FG Leopard STX, FG Marder Beetle, FG Pajero and most other large scale cars.


On-road Rc Cars: MCD, FG Evo,FG Sportline, HARM,FG F-1 Competition and most other large scale onroad cars.

This engine does not come with clutch or carb, this can be added here

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CNC Ported Full Mod Zenoah 30.5cc 4 Bolt Engine - High Rev

  • Product Code: 6021
  • Availability: In Stock
  • £300.00