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> How is this revolutionary motor being outdone by a mid-range sedan engine? Go ask your Camry engine to make 100% rated power indefinitely, and see how long i

by Syonyk 4y ago

> How is this revolutionary motor being outdone by a mid-range sedan engine? Go ask your Camry engine to make 100% rated power indefinitely, and see how long it holds up. That's the difference. A typical car engine is designed to make 30-50hp sustained, and occasionally generate more power for reasonably short periods of time. An aviation engine, generator engine, or any sort of "industrial" engine is going to be able to sit there, making full rated horsepower, for thousands of hours without any trouble at all.

causi 4y ago
going to be able to sit there, making full rated horsepower, for thousands of hours without any trouble at all. The XTS-210 can do that?
- Syonyk 4y ago
  If it's an aviation engine, it'd better be able to!
  - someweirdperson 4y ago
    Multiple thousand at max power? Typically, overhaul at 2000 hours. And maximum continous power isn't usually full load.
    - Syonyk 4y ago
      It really depends on the engine, but almost all the general aviation engines you'll find (Lycoming and Continental 4s, and the smaller 6s) are rated for continuous operation at full power, and if they're flown regularly, will typically make well past the 2000-3000 hour TBO (which is a recommendation/expectation, not a legal requirement, though I believe some of the small diesels can't be operated past it). Our flying club engines in the 172s typically make at least 3000, if not 3500 hours, and I think some of the overhauls at that point have been a "Well... it's still perfectly fine... but..." thing where the board was just starting to get uncomfortable with the hours on it. And, yes, they spend a lot of time making less than rated power, because of density altitude, but they're still rated for full power operation, and since there's basically no wear going on with an engine in operation (almost all the wear is during starting), there's no real difference there. It's not until you get into the really large engines where "maximum continuous" is a different thing from "takeoff power." The turbocharged 500s are about the smallest I know of with that sort of rating, and even then I don't think it's all of them. Most of the big radials have that limit, though. If you find a smaller plane with that sort of limit, it's either a possible resonance issue between the engine and prop, or a noise regulation for certification.
kube-system 4y ago
IIRC some automakers do test automotive engines at 100% duty cycle (in a test stand configuration). And more than a few automotive engines are used in slightly modified variants for marine and aviation applications. As I understand, the reason a typical car engine can’t sit at 100% duty cycle isn’t the engine itself, but usually the cooling and oiling configuration. Examples: https://youtu.be/GNPB3RtHN2M https://youtu.be/GNPB3RtHN2M https://www.vikingaircraftengines.com/engine-options https://www.vikingaircraftengines.com/engine-options
- ghostpepper 4y ago
  The first time I learned you can increase, sometimes significantly, the performance of a car by upgrading the oil cooler blew my mind a little bit, but of course in hindsight it makes perfect sense.
  - Iwan-Zotow 4y ago
    WW2 planes engines
- Syonyk 4y ago
  I'm aware of some auto engine conversions - the 13Bs out of the RX-7s and related could do it, the older Subaru engines (EA81) would do it, but they're just a small aircraft engine in a car, design-wise... Looking over the Viking engines, I don't think it's fair to call those "automotive engines," because my read of the description of what they do means they're pulling it apart and replacing an awful lot of pieces. They claim they're "based on" the latest Honda engines, and once you're starting to change the cylinder bore offset, custom hone the cylinders, replace your pistons and conrods, etc, it's no longer a car engine.
  - kube-system 4y ago
    If changing those minor attributes makes an engine "not a car engine" then the majority of race cars also don't have car engines. On their About page, they themselves say: > Companies like Honda and Mitsubishi have spent millions of dollars refining and testing. We don’t claim that we can outsmart either company when it comes to the design of any internal running component of these engines. We don't change vital engine parameters around and claim we have different models. The compression, etc. is all stock. Every part is OEM Honda / Mitsubishi, nothing is new aftermarket from unknown origins. > We start with the most up to date year engines with super low mileage, derived from fender benders across the US. When customers want the information about where there engine core came from and how many miles it had - we have all that documentation readily available to show. Literally, every one of these engines came out of a car. I think that plainly qualifies it as a car engine.

by Syonyk 4y ago

causi 4y ago

going to be able to sit there, making full rated horsepower, for thousands of hours without any trouble at all. The XTS-210 can do that?

Syonyk 4y ago
If it's an aviation engine, it'd better be able to!
- someweirdperson 4y ago
  Multiple thousand at max power? Typically, overhaul at 2000 hours. And maximum continous power isn't usually full load.
  - Syonyk 4y ago
    It really depends on the engine, but almost all the general aviation engines you'll find (Lycoming and Continental 4s, and the smaller 6s) are rated for continuous operation at full power, and if they're flown regularly, will typically make well past the 2000-3000 hour TBO (which is a recommendation/expectation, not a legal requirement, though I believe some of the small diesels can't be operated past it). Our flying club engines in the 172s typically make at least 3000, if not 3500 hours, and I think some of the overhauls at that point have been a "Well... it's still perfectly fine... but..." thing where the board was just starting to get uncomfortable with the hours on it. And, yes, they spend a lot of time making less than rated power, because of density altitude, but they're still rated for full power operation, and since there's basically no wear going on with an engine in operation (almost all the wear is during starting), there's no real difference there. It's not until you get into the really large engines where "maximum continuous" is a different thing from "takeoff power." The turbocharged 500s are about the smallest I know of with that sort of rating, and even then I don't think it's all of them. Most of the big radials have that limit, though. If you find a smaller plane with that sort of limit, it's either a possible resonance issue between the engine and prop, or a noise regulation for certification.

kube-system 4y ago

IIRC some automakers do test automotive engines at 100% duty cycle (in a test stand configuration). And more than a few automotive engines are used in slightly modified variants for marine and aviation applications. As I understand, the reason a typical car engine can’t sit at 100% duty cycle isn’t the engine itself, but usually the cooling and oiling configuration. Examples: https://youtu.be/GNPB3RtHN2M https://youtu.be/GNPB3RtHN2M https://www.vikingaircraftengines.com/engine-options https://www.vikingaircraftengines.com/engine-options

ghostpepper 4y ago
The first time I learned you can increase, sometimes significantly, the performance of a car by upgrading the oil cooler blew my mind a little bit, but of course in hindsight it makes perfect sense.
- Iwan-Zotow 4y ago
  WW2 planes engines
Syonyk 4y ago
I'm aware of some auto engine conversions - the 13Bs out of the RX-7s and related could do it, the older Subaru engines (EA81) would do it, but they're just a small aircraft engine in a car, design-wise... Looking over the Viking engines, I don't think it's fair to call those "automotive engines," because my read of the description of what they do means they're pulling it apart and replacing an awful lot of pieces. They claim they're "based on" the latest Honda engines, and once you're starting to change the cylinder bore offset, custom hone the cylinders, replace your pistons and conrods, etc, it's no longer a car engine.
- kube-system 4y ago
  If changing those minor attributes makes an engine "not a car engine" then the majority of race cars also don't have car engines. On their About page, they themselves say: > Companies like Honda and Mitsubishi have spent millions of dollars refining and testing. We don’t claim that we can outsmart either company when it comes to the design of any internal running component of these engines. We don't change vital engine parameters around and claim we have different models. The compression, etc. is all stock. Every part is OEM Honda / Mitsubishi, nothing is new aftermarket from unknown origins. > We start with the most up to date year engines with super low mileage, derived from fender benders across the US. When customers want the information about where there engine core came from and how many miles it had - we have all that documentation readily available to show. Literally, every one of these engines came out of a car. I think that plainly qualifies it as a car engine.