Bucker Hirth replacement idea

[Lionheart]

Hey guys,


You ever see the classic planes that once had that verticle front nose cowling (like a Bucker Jungmann Bu-131 or a Tiger Moth) that have been replaced with a wide, flat cowling with a Lycomming or Continental under the hood?

arrghhhhh..

I was thinking, what if you had an alternative to the Hirth engine (straight 4 that was in the old Buckers. Same size, area, etc).

And it occurred to me. The Audi / VW V-6 that uses 3 sleeves between 3 sleeves in a tight V that is almost straight up. The design enables a V-6 to fit in a 4 cylinder car. That might just fit in a Bucker or Tiger Moth. The engine has a single head that fits over all cylinders. (Thats how narrow it is). The engine might even produce far more power to weight then the original. (The new Audi design is all aluminum from what I remember).

There would need to be a gearbox to bring the output shart up top with the prop axis. The engine would need to also be moved back to compensate for the longer block as well...

I wonder what it would sound like.


arghh.. It is a water cooled engine though. I didnt think about that.

[Drzook]

You could always go with a LOM engine. Air cooled inverted fours and sixes. Not sure if they are still in production however; the north american distributor (moravia inc) website implies they are no longer in current production. If this is the case that would truly suck.
http://www.zenithair.com/stolch801/engine-walter-lom.html
I've always been a sucker for straight-sixes myself, but the four seems pretty good for tiger moths and jungmanns.:d

Walter-LOM M332B
160 HP, 4 cylinder
http://www.zenithair.com/stolch801/images/moravia-wl1.jpg
M332B Engine Specifications:

M332B Engine Features:

<SMALL>SMALL FRONTAL AREA</SMALL>
<SMALL>INLINE - INVERTED</SMALL>
<SMALL>FOUR STROKE </SMALL>
<SMALL>DIRECT DRIVE </SMALL>
<SMALL>AIR COOLED </SMALL>
<SMALL>OVERHEAD CAMSHAFT </SMALL>
<SMALL>HEMISPHERICAL COMBUSTION SPACE </SMALL>
<SMALL>LOW SPECIFIC FUEL CONSUMPTION </SMALL>
<SMALL>ALT. COMPENSATED FUEL INJECTION </SMALL>
<SMALL>2,000 HOURS TBO </SMALL>

[Lionheart]

Thanks for the info Dr. Zook!

:ernae:

That looks amazingly similar to a Hirth. Perhaps even the same mounting points.



Bill

[Ferry_vO]

VW stopped making their VR5 and VR6 engines some time ago IIRC. :)

I doubt that a modern car engine would make a good aircraft engine though, as most aircraft engines will need to run at a continous RPM for a long time, and a car engine will need to revv quite high to produce the maximum power which will not be good for the reliability.

The engine in a Cessna Centurion has a capacity of 520 Cu.in. (8.5 liter; more than a Dodge Viper!) but produces only 310 bhp. It does however produce this power at a relatively low rpm so the reliability is still very good. And watercooling is a definite disadvantage too when it comes to being reliable; the less parts there are, the less chance of something going kaput.

:)

[JoeW]

Cams can be ground that will produce the power at at a lower RPM. There used to be, in the 60's, a grind for a sawmill for Fords and Chevys, That produced the Torque and HP at 2500 RPM that the regular stock grind produced at 4000 RPM.
I learned that the hard way. I ran (Dragrace) against one on the street and that thing was a great instant 60 MPH off the line. Hard to catch on down the way.
:jump:

[Lionheart]

VW stopped making their VR5 and VR6 engines some time ago IIRC. :)




Drats... I thought it was a good idea. :banghead:

Good points on the low RPM. I had never thought about that. I almost wonder why they dont do that with cars?

I had seen a website the other day where a guy in Australia was remaking old Austin Healey engine blocks again. (I think it was AH blocks). Showed all the intricate wooden casting crates (sand formers) that all fit together to make the sand block that the Aluminum (or iron) is poured into. Too bad he doesnt have CNC equipment. Would certainly make it more faster and precise. You look at how Ferrari makes engines now at their newest factory and they make it look so darn easy. So much elaborate computer sophistication that its crazy..... Enter the program, push a button, and in a couple of min's, a block of molded aluminum becomes a 4 port twin cam head....

The future...!


Bill