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carey shurley · 04-30-2014, 12:56 PM

G320 RC Engine

Since last year there have been rumors that Zenoah was going to produce a new larger displacment engine. So just this month they have made available a new 32cc class engine (actually its 31.5cc in displacement). Its officially going to be available in the RC and PUM (marine) formats although there hasn't been any info about a PUH (helicopter) version

As we've talked about before, helicopters use either the PUH or RC formats of the zenoah engines. Most of the newer designed models either use the RC format or have a version that will. Regardless if they provide a PUM version of the engine, the modifiers will convert them into PUH versions, you can count on that

Here's the complete engine as it comes from Zenoah

Zenoah G320 RC engine complete

Looking at the engine from the bottom view, its very similar to the existing G2x0 RC engines

Case Bottom view lr

BUT its not the same. Here you can start to see differences. The cylinder is a different design. The transfer ports have removeable covers on them for one thing. There are several reasons they did this however a side benefit is that for those folks that modify these, its easier to get their tools in to modify port size/shape and timing. You can see that the cooling shroud is also different. For those helicopters where the air blows out the top of the model its yet to be seen how this new shape will affect that air flow

Rear View

The engine uses the Walbro 1107 carburetor. This is new for the RC engine line. Not sure what all is different, it seems to have the same bore as the WT990 carb however

Carburetor

WIth the cooling shroud off you can better see the port covers. The exhaust mounting is the same as the other RC engines so your existing mufflers will mount................now whether they have enough volume for this engine is yet to be seen

Cylinder View

As I noted earlier, it LOOKs like the other RC format engines but its not. The crankcases are new. The crank bearings are larger and as a result the mount dimensions for the nose of the engine have changes. If you are running this in an RC car where they use the original clutch and housing (see earlier photo) then the engine will likely bolt right in. However for helicopters this housing is removed and they mount directly to the case.

Because of the change, as of this writing this engine will not fit into any existing helicopter that uses the RC engine format. This will of course change but at the moment its an issue

Nose Dimensions

The thickness/height of the case is changed as well, its slightly thicker than the other RC format engines. I measured at all 4 corners and got a measurement that varied between 85.1 mm and 86.3 mm. These are castings, I have to assume that plays a role in the changes. The average is 85.7mm

Case Dimensions

The Bottom Line

So Zenoah has changed the rules again for model helicopters by producing this engine. Not much is known about its performance yet but I suspect that out of the box, it will NOT perform as well as the smaller engines being delivered by the main modifiers (BH Hanson, HWC, TRM). However I can tell you that they are already workiing on modification packages for these

The big issue at the moment is that the engine will fit your RC car or Go Ped, but it won't fit into your model helicopter without making modifications..............Thats only a matter of time though

ocr231 · 04-30-2014, 08:32 PM

I have run 3 of the engines now.2 that were stock and 1 that was just balanced.

I dont think it is a good heli engine out of the box.It will make power up to 12,7 rpms but it vibrates to much there.The engine that B.H balanced was ok up to 12.7 but over that it vibrated.

The engine also seems to run hot.On just average flying i was getting temps in the 300s.

As for the carb it tunes like a 643,meaning the low needle will affect hover and mid range and the high needle is tuned for power.I tried the new carb and the 990 back to back and the new carb in my opinion works better with this engine.

Another thing that is different with this engine is the isolator block.The side that mounts to the engine is different than the 270s and 300s.The stock block on the new engine does the same thing as the older ones did where the inserts move in the block allowing air to get bye.Al at B.H .Hanson has a aluminum block for the new engine.I dont know if anybody else does yet.

04-30-2014, 12:56 PM	#1 (permalink)
carey shurley Registered Users Join Date: Apr 2004	Engines - Zenoah G320 RC Overview G320 RC Engine Since last year there have been rumors that Zenoah was going to produce a new larger displacment engine. So just this month they have made available a new 32cc class engine (actually its 31.5cc in displacement). Its officially going to be available in the RC and PUM (marine) formats although there hasn't been any info about a PUH (helicopter) version As we've talked about before, helicopters use either the PUH or RC formats of the zenoah engines. Most of the newer designed models either use the RC format or have a version that will. Regardless if they provide a PUM version of the engine, the modifiers will convert them into PUH versions, you can count on that Here's the complete engine as it comes from Zenoah *Zenoah G320 RC engine complete* Looking at the engine from the bottom view, its very similar to the existing G2x0 RC engines *Case Bottom view lr* BUT its not the same. Here you can start to see differences. The cylinder is a different design. The transfer ports have removeable covers on them for one thing. There are several reasons they did this however a side benefit is that for those folks that modify these, its easier to get their tools in to modify port size/shape and timing. You can see that the cooling shroud is also different. For those helicopters where the air blows out the top of the model its yet to be seen how this new shape will affect that air flow *Rear View* The engine uses the Walbro 1107 carburetor. This is new for the RC engine line. Not sure what all is different, it seems to have the same bore as the WT990 carb however *Carburetor* WIth the cooling shroud off you can better see the port covers. The exhaust mounting is the same as the other RC engines so your existing mufflers will mount................now whether they have enough volume for this engine is yet to be seen *Cylinder View* As I noted earlier, it LOOKs like the other RC format engines but its not. The crankcases are new. The crank bearings are larger and as a result the mount dimensions for the nose of the engine have changes. If you are running this in an RC car where they use the original clutch and housing (see earlier photo) then the engine will likely bolt right in. However for helicopters this housing is removed and they mount directly to the case. Because of the change, as of this writing this engine will not fit into any existing helicopter that uses the RC engine format. This will of course change but at the moment its an issue *Nose Dimensions* The thickness/height of the case is changed as well, its slightly thicker than the other RC format engines. I measured at all 4 corners and got a measurement that varied between 85.1 mm and 86.3 mm. These are castings, I have to assume that plays a role in the changes. The average is 85.7mm *Case Dimensions* The Bottom Line So Zenoah has changed the rules again for model helicopters by producing this engine. Not much is known about its performance yet but I suspect that out of the box, it will NOT perform as well as the smaller engines being delivered by the main modifiers (BH Hanson, HWC, TRM). However I can tell you that they are already workiing on modification packages for these The big issue at the moment is that the engine will fit your RC car or Go Ped, but it won't fit into your model helicopter without making modifications..............Thats only a matter of time though __________________ Carey Shurley Proprietor - Gas Powered Helicopters Last edited by carey shurley; 04-30-2014 at 04:16 PM..

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04-30-2014, 08:32 PM	#2 (permalink)
ocr231 Registered Users Join Date: Apr 2008	I have run 3 of the engines now.2 that were stock and 1 that was just balanced. I dont think it is a good heli engine out of the box.It will make power up to 12,7 rpms but it vibrates to much there.The engine that B.H balanced was ok up to 12.7 but over that it vibrated. The engine also seems to run hot.On just average flying i was getting temps in the 300s. As for the carb it tunes like a 643,meaning the low needle will affect hover and mid range and the high needle is tuned for power.I tried the new carb and the 990 back to back and the new carb in my opinion works better with this engine. Another thing that is different with this engine is the isolator block.The side that mounts to the engine is different than the 270s and 300s.The stock block on the new engine does the same thing as the older ones did where the inserts move in the block allowing air to get bye.Al at B.H .Hanson has a aluminum block for the new engine.I dont know if anybody else does yet.

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