aircraft engine sizes (hp)?

[Airhead]

Would somebody please explain how the aircraft engine designations which I'm assuming are cubic inches such as a continental 220 or a lycoming 540 equate to actual horsepower. For example, I saw where a lycoming 235 is approx 115 hp and where I believe a cont 300 is approx 150 hp. Is there a ratio there I can use as a rule of thumb? It seems that the hp is approx 1/2 of cubic inches. Is this right? If that's the case then the cont 220 is approx 110 hp and the lycoming 540 is 270 hp.

I hope this is not too stupid a question.

Thanks

 

[marshmaster pat]

It might work for a really rough idea of the HP, but would never get you closer than about 30 hp. Also some engines with the same displacement are rated at different maximum RPM ratings due to being used on different aircraft. With Lycomings there are quite a few different engine models and they have quite a few HP ratings. Some are normal carburatored, fuel injected, or turbocharged.

On Lycomings here are a few hp ratings.

0-540 angle valve with fuel injection about 300 HP @ 2700 RPMs
0-540 angle valve with standard carburator about 290 HP @ 2700 RPMs
0-540 parallel valve with standard carburator about 260 HP @ 2700 RPM

I have a friend with an 0-540 parallel valve rated at 230 HP @ 2350 RPM according to the engine plate. But it is turning the same propeller at the same pitch and the same RPMs as several 260 HP engines.

TIO-360 produce 220 HP, turbocharged and fuel injected.
There are several variations with the 0-360, 200 HP, 180 HP, and the above.

Hope this helps some

 

[rick]

Here's most of the Lycomings:
http://www.prime-mover.org/Engines/Lycoming/Lyc_Cert_list.html

Here's some of the Continentals:
http://www.tcmlink.com/visitor/engSpecSheetsFramesVIS.cfm

Like marshmaster pat said, some engines with the same cubic inches and same compression have different horsepower ratings because of the rpm's they're rated at.

 

[Anonymous]

Would somebody please explain how the aircraft engine designations which I'm assuming are cubic inches such as a continental 220 or a lycoming 540 equate to actual horsepower

Well, I think that 220 is a HP rating on an 0470 GPU........

I've wondered also if the 0470 and 0540 numbers are cubic inch displacement numbers.....is this true? And what's the "0" for?

 

[jim]

They are cubic inch numbers. "O" stands for opposed, (opposed cylinders). "R" would mean radial.
An R985 is a 985 cubic inch radial.
Check out the Lycoming link posted by Rick, it explains a bunch of letters.

Jim

 

[Anonymous]

Thanks.

That is a neat link, I overlooked it before

 

[jim]

Check out the R4360:

http://www.pw.utc.com/about_history_classic_r4360.asp

It also powered the Spruce Goose.

Jim

 

[marshmaster pat]

There is something awesome about those big radials. Thanks for the link.

 

[jim]

Pat,

I flew airplanes with big radials on them. It was fun to hear and feel them start up.

Jim

 

[Anonymous]

Holy cow, 4360! Neat how they spiraled the cylinders to make it run smoother.