Radialconversions
Active Member
I’ve been asked to copy my post over here from my Facebook page. I hope everyone finds this informative.
So the other week I did an up close inspection of the Verner Scarlet S9 for a customer of mine. He was considering using this engine in his project and wanted me to develop the firewall forward for this engine as an option. After the inspection we decided that the Rotec was the only engine that would be able to meet his requirements. It’s disappointing but I can’t see this engine being a viable alternative. Here are the basics what I found.
Pros:
-The engine is higher displacement
-The ignition system is coil on plug
-The fuel system is an EFI
-The electrical harness is fully developed
Cons:
-Direct drive, lose engine efficiency
-Intake pipes are plastic and located directly across from an exhaust port.
-the distance between the plastic intake pipes and exhaust port is minimal requiring a hard bend in the exhaust pipe. If the pipe cracks the intake will be compromised.
-There is no exhaust system provided.
-Cylinders are a modified Honda cylinder head
-Second spark plug drilled right next to the primary, setting up for potential cracking.
-The oil system is a wet sump design requiring the top of the oil tank be at least 30mm below the engine when the aircraft is in a level attitude. Hard to do on a round airplane.
-The alternator is limited to 200w or 16.67amps. This doesn’t leave much margin for other electrical components on the aircraft since the engine is fully electric and requires a full time high pressure electric fuel pump.
-The alternator is built into the prop hub making maintenance difficult.
-The prop hub is non standard making it hard to use any standard Propellers on the market.
-The prop bolts are non standard, Internal wrenching, non safetying bolts that are roughly half the size of normal prop bolts.
-it’s priced at $31,000 vs $27,500 for the R-3600.
-Lastly, the engine has never flown.
Anyways I hope this report helps, please comment below with any additional questions on my observations.
So the other week I did an up close inspection of the Verner Scarlet S9 for a customer of mine. He was considering using this engine in his project and wanted me to develop the firewall forward for this engine as an option. After the inspection we decided that the Rotec was the only engine that would be able to meet his requirements. It’s disappointing but I can’t see this engine being a viable alternative. Here are the basics what I found.
Pros:
-The engine is higher displacement
-The ignition system is coil on plug
-The fuel system is an EFI
-The electrical harness is fully developed
Cons:
-Direct drive, lose engine efficiency
-Intake pipes are plastic and located directly across from an exhaust port.
-the distance between the plastic intake pipes and exhaust port is minimal requiring a hard bend in the exhaust pipe. If the pipe cracks the intake will be compromised.
-There is no exhaust system provided.
-Cylinders are a modified Honda cylinder head
-Second spark plug drilled right next to the primary, setting up for potential cracking.
-The oil system is a wet sump design requiring the top of the oil tank be at least 30mm below the engine when the aircraft is in a level attitude. Hard to do on a round airplane.
-The alternator is limited to 200w or 16.67amps. This doesn’t leave much margin for other electrical components on the aircraft since the engine is fully electric and requires a full time high pressure electric fuel pump.
-The alternator is built into the prop hub making maintenance difficult.
-The prop hub is non standard making it hard to use any standard Propellers on the market.
-The prop bolts are non standard, Internal wrenching, non safetying bolts that are roughly half the size of normal prop bolts.
-it’s priced at $31,000 vs $27,500 for the R-3600.
-Lastly, the engine has never flown.
Anyways I hope this report helps, please comment below with any additional questions on my observations.
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