Navion Thoughts
- Thread starter JasonCT
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docmirror
Touchdown! Greaser!
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Cowboy - yeehah!
I think he was tripped up because the engine is an 'E-185' with 205HP for takeoff. A C205 is indeed an airplane moniker.
Skylane81E
Final Approach
Yeah probably my fault on that one
bnt83
Final Approach
The E-185's could be modded for 205HP for two minutes or something like that. It's still an E-185 even if people like to call it a 205.
docmirror
Touchdown! Greaser!
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Cowboy - yeehah!
It is not a modification. The engine TC from the factory allows operation at 2600RPM for five minutes on the E-185-11 providing 205HP. Max cont is 185 @ 2300.
The E-225 allows five min of operation at 2650 providing 225HP, max cont is still 185 @ 2300.
How they got the extra 20HP out of 50 RPM, I'll never know. The cams are different, and the carb is different, so I guess????
It is not a modification. The engine TC from the factory allows operation at 2600RPM for five minutes on the E-185-11 providing 205HP. Max cont is 185 @ 2300.
The E-225 allows five min of operation at 2650 providing 225HP, max cont is still 185 @ 2300.
How they got the extra 20HP out of 50 RPM, I'll never know. The cams are different, and the carb is different, so I guess????
That would be fine if the Navion came with a -11 engine. It only came with the -3 or -9. Anyway, to tell if you can get 205 5 min take-off rating you have to ascertain your engine has the Dampened (D-stamped serial number) crankshaft. If it doesn't have this, it's hard limited to 185. To actually make use of this you also need the 8433 prop blades
As for the E-225, actually the crank should be the same as for the -11 (and some modded -8's) but the jugs are bigger.
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It is not a modification. The engine TC from the factory allows operation at 2600RPM for five minutes on the E-185-11 providing 205HP. Max cont is 185 @ 2300.
The E-225 allows five min of operation at 2650 providing 225HP, max cont is still 185 @ 2300.
How they got the extra 20HP out of 50 RPM, I'll never know. The cams are different, and the carb is different, so I guess????
I'll bet you see a higher MP number as well. The cam and fuel/air restrictions were reduced so more mix could make it into those cylinders with just those 50 more RPM reducing manifold vacuum.
docmirror
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Cowboy - yeehah!
Yes, I know. I own several of them. Your statement about the 'modification' was still wrong, although I guess you could go to the trouble of finding a non dampened engine, taking it apart, removing the crank, replacing it with the dampened crank, installing all the stuff again, changing the data plate to a 'D' prefix, and certifying it as a -3, or -8, -9, or -11 as req.
Unless, of course you had the Marvel carb in which case, no matter the crank, you are once again limited to 185HP. And that, I believe should be about the last bit of minutia we cover on the E series engines.
Oh, you forgot the ever popular(not) -4 engine which was rated at 224HP @ 2600.
<edit: the jugs are not bigger. 471CI for each. The pn for the 185 and 225 cylinders are interchangable(except a few early PN where the fins will not dissipate the added heat, but most are out of service by now). The '727' jugs are the preferred part for both engines, but there are others that will fill the bill.
Just to jump in here, I have a 1946 North American built NAvion with a IO-550-B in it. I don't have the nose gear doors installed yet but I get 165KTAS at 7000' in the winter and 155KTAS at 7000' in the summer. That is burning 14 to 15 GPH. I run rich of peak and 2400 RPM.
Cheers
Cheers
If you are seripus about Navions you shpould join the Navion group on Yahoo. There are a lot of people there who can intelligently answer your questions. Try here:
http://groups.yahoo.com/group/navion_aircraft_mail/
Tony Russell
http://groups.yahoo.com/group/navion_aircraft_mail/
Tony Russell
JasonCT
Pattern Altitude
Thanks Andy I prob will want to chat with him.
The real question is......is it Navy On or Nav EE On
The real question is......is it Navy On or Nav EE On
You'll find most of the owners say NAY vee on. Sort of in deference to the original NAvion spelling (it was built my North American). However, we won't shun you if you say NAV ee on.
gismo
Touchdown! Greaser!
It's strange that you get lower TAS with the higher DA of summer using the same power (fuel flow). Normally a higher DA yields more TAS because that higher TAS comes at a lower IAS which is closer to your best range (max efficiency) IAS.
I never thought of it that way. Just know that when it is ISA+ a lot the TAS is a lot lower. In winter when it is closer to ISA it flies faster. Same with all the TurboProps and Jets I have flown. The other day in a King Air 350 at FL300 we left VA at ISA and TAS of 302 kts. In the Bahamas it was ISA +12 and we could only get 285. Been that way for as long as I can remember. I think it is related to the fact that the denser air at lower temps gives more power and vice versa.
Try running LOP.
By the way guys, if you are really interested in Navions, the American Navion Society is holding their 53rd annual convention in Paso Robles June 23-28. You can see lots of Navions, sit in on our technical forums, talk to Navion owners plus we have many socical events (tours, dinners) throughout the week for pilots and non-pilots alike.
Information is available is available at the
http://www.navionsociety.org/old/convention.html
Information is available is available at the
http://www.navionsociety.org/old/convention.html