Top Ends & Parts

Replacement 36mm Piston for 30.5cc G290 Engines

<p>(Our porting is not shown in picture)&nbsp;</p> <p>PROSTOCK - An affordable/mild version of a full mod. The PROSTOCK's are rated at 5-5.5hp, full mod's 6-6.5hp, and full mod long rods 7-7.5hp.&nbsp;<span style="color: #000000;">We guarantee performance of this top end to be as much if not more than similary priced ported top ends from our competitors.&nbsp;</span></p> <p>The PROSTOCK line has replaced the Race Ported line. The PROSTOCK engines produce more power than the race ports and are more economical.</p> <p>To keep costs down, we focused our time tuning this top end to the areas that would yield the most power possible while maintaining reliability and ease of use. At OBR, we do not believe in stacking or using thick cylinder gaskets. We always machine and reshape the combustion chamber on our stroked engines. To help with reliability, we also relieve the piston. Piston reliefs help reduce the chances of the piston seizing on the exhaust side of the cylinder when running lean or hot. We were the first in this industry to do the piston relief several years ago.</p> <p>Being that this line is a budget/starter top end, we tuned it to run well with any exhaust. We kept in mind that you may not have a pipe. We have seen great performance with everything from an HPI can exhaust to a pipe. If upgrading to a pipe, we recommend the Jetpro Boss. For those of you that are new to ported engines, we shot for ease of use. With proper installation a PROSTOCK engine is very easy to start and to tune the carb.&nbsp;</p> <p>We have left the porting open on this top end. At any time, you may send your engine/top end in to us to be upgraded to a full mod or a full mod long rod.</p> <p><span style="color: #ff0000;">*Tech notes: We have ported this top end to not need a modified crankcase. We recommend a standard Zenoah 4 bolt crankcase. This top end requires that you use a +1mm stroker crankshaft.&nbsp;</span></p>

<p>(Our porting is not shown in picture)<br />This is a brand new race ported 28.5cc G290RC 4 bolt top end. This kit comes with a hand ported G290RC cylinder, piston, ring, wrist pin, c-clips, spark plug, needle bearing and base gasket. The following port work has been done:</p> <p><br />1. Resurface all ports for better gas/air mixture<br />2. Modify transfer ports for better flow<br />3. Enlarge and reshape exhaust port<br />4. Exhaust timing raised to our specs<br />5. Re bevel all porting and factory bevels to prevent damage to the top end</p>

<p>This 28.5cc big bore kit has been race ported by us for the best performance possible. The intake, exhaust, and transfer ported have been enlarged and reshaped for maximum performance.</p> <p><br />This big bore kit fits the following:</p> <p><br />Motors: G230RC, G260RC, St23rc, St27rc, He23hp, He26hp.</p> <p>Off-road Rc Cars:HPI Baja 5B/5T/5SC, FG Marder,FG Marder Race,FG Monster Beetle,FG Monster Beetle Pro,FG MT5,FG Stadium Truck, Duratrax Firehammer, Carson Attack, Smartech Travel,ler,FG Leopard, XTM<br />Leopard Race,FG Leopard STX,FG Marder Beetle,FG Pajero, And most other large scale cars</p> <p>On-road Rc Cars: FG Evo-4,FG Sportline, HARM,FG F-1 Competition, And most other large scale on-road cars.</p>

Replacement thrust washer set for all Zenoah engines 22.5cc's-30.5cc's.

Replacement piston needle bearing for all Zenoah engines.

Replacement Piston for Full Mod GP470 Engine

Replacement 38mm Piston for G340RC Engines

<p>This is a brand new race ported Zenoah 27.2cc big bore kit. This kit requires a 2mm stroker (not included). To start we machine the cylinder for the 2mm stroker and for a proper squish clearance with out stacking gaskets. This allows the motor to rev higher and still have a massive amount of torque. All of our port work is done by hand except for machining the cylinder. The following port work has been done:</p> <p><br />1.Machined Cylinder For 2mm Stroker<br />2. Resurfaced intake port<br />3. Enlarged and resurfaced exhaust port<br />4. Reshaped/Resurfaced/Enlarged transfers ports</p> <p><br />This big bore kit will fit the following Motors/Cars/Trucks:</p> <p>Motors(2mm Stroker Required): G230RC, G260RC, CY23rc,CY26rc, CY27rc, CY29rc,GP290, 27cc Head Kit Motor, 29cc Head Kit Motor He23hp, He26hp.</p> <p>Off-road Rc Cars: HPI Baja 5B/5T/5SC, FG Marder,FG Marder Race,FG Monster Beetle,FG Monster Beetle Pro,FG MT5,FG Stadium Truck, Duratrax Firehammer, Carson Attack, Smartech Travel,ler,FG Leopard, XTM<br />Leopard Race,FG Leopard STX,FG Marder Beetle,FG Pajero, And most other large scale cars</p> <p>On-road Rc Cars: FG Evo-4,FG Sportline, HARM,FG F-1 Competition, And most other large scale on-road cars.</p>

This is a brand new race ported 30.5cc upgrade kit. This kit comes with everything need to turn your motor into a beast. To start we machine the cylinder for the 2mm stroker and for a proper squish clearance with out stacking gaskets. This allows the motor to rev higher and still have a massive amount of torque. All of our port work is done by hand except for machining the cylinder. Kit includes a complete top end (cylinder, piston, ring, piston hardware) and a CY 2mm unstuffed crank.

This big bore kit will fit the following Motors/Cars/Trucks:

Motors: G230RC, G260RC, CY23rc,CY26rc, CY27rc, CY29rc,GP290, 27cc Head Kit Motor, 29cc Head Kit Motor He23hp, He26hp.

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

On-road Rc Cars: FG Evo-4,FG Sportline, HARM,FG F-1 Competition, And most other large scale on-road cars.

Replacement CY intake manifold. Fits all CY and Zenoah engines from 22.5cc's-30.5cc's.

Replacement piston ring for the G260RC and G270RC engines. This piston ring is also used in our race ported and full mod Zenoah 27.2cc engines.

Zenoah Intake Manifold for G320RC & G340RC Engines

Replacement Top End for 6023 - Signature Series Dirt Oval Mod Zenoah 4 Bolt 30.5cc engine.

Replacement Piston for Full Mod GP460 Engine

Replacement CY 35mm Piston Ring

Replacement Wrist Pin for G290RC 36mm Piston. Fits 28.5cc-30.5cc

<p>This is a brand new race ported Zenoah 27.2cc big bore kit with 2mm stuffed crank. This kit comes with everything need to turn your motor into a beast. To start we machine the cylinder for the 2mm stroker and for a proper squish clearance with out stacking gaskets. This allows the motor to rev higher and still have a massive amount of torque. All of our port work is done by hand except for machining the cylinder. The following port work has been done:</p> <p><br />1.Machined Cylinder For 2mm Stroker<br />2. Resurfaced intake port<br />3. Enlarged and resurfaced exhaust port<br />4. Reshaped/Resurfaced/Enlarged transfers ports</p> <p><br />This big bore kit will fit the following Motors/Cars/Trucks:</p> <p>Motors: G230RC, G260RC, CY23rc,CY26rc, CY27rc, CY29rc,GP290, 27cc Head Kit Motor, 29cc Head Kit Motor He23hp, He26hp.</p> <p>Off-road Rc Cars: HPI Baja 5B5T/5SC, 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<br />Leopard Race,FG Leopard STX,FG Marder Beetle,FG Pajero, And most other large scale cars</p> <p>On-road Rc Cars: FG Evo-4,FG Sportline, HARM,FG F-1 Competition, And most other large scale on-road cars.</p>

Replacement 38mm Piston for G320RC Engines

Replacement 36mm Piston for 29.5cc G290 Engines

Replacement 36mm Piston for 28.5cc G290 Engines

<p>This Zenoah 25.4cc big bore kit has been race ported for maximum performance. The intake, exhaust and transfer ports have been opened up for the best possible performance.</p> <p><br />This kit fits the following:</p> <p>Motors: G230RC, G260RC, St23rc, St27rc, He23hp, He26hp.</p> <p>Off-road Rc Cars:HPI Baja 5B/5T/5SC, FG Marder,FG Marder Race,FG Monster Beetle,FG Monster Beetle Pro,FG MT5,FG Stadium Truck, Duratrax Firehammer, Carson Attack, Smartech Travel,ler,FG Leopard, XTM<br />Leopard Race,FG Leopard STX,FG Marder Beetle,FG Pajero, And most other large scale cars</p> <p>On-road Rc Cars: FG Evo-4,FG Sportline, HARM,FG F-1 Competition, And most other large scale on-road cars.</p>

Replacement piston needle bearing for all CY engines 22.5cc's-30.5cc's.