Installing airplane engine in 911

[octanemaestro]

I've searched the web for this and also searched all the forums on here and haven't found anything. I know that Porsche developed a short lived airplane engine based on the 911 engine and produced about 80 units of the Porsche PFM 3200. Has anyone ever heard or seen an installation of any aircraft engine in a 911, the PFM 3200 or otherwise? Setting aside authenticity for a moment, any technical reason why someone wouldn't wouldn't use say an aircooled Continental horizontally opposed dry sump 6 six-cylinder if they had an engineless 911 and an extra low hours airplane engine of comparable size, weight and horsepower to the original 911 engine? Seems like it would fairly simply shoehorn in and run pretty much the same, maybe it would even run better or be better somehow. Certainly it would be better than no engine at all!

[winders]

You mean other than the fact that those Continental engines were low RPM (2500 RPM) engines that were not designed to be used over a large RPM range? How would you cool it? You would need to come up with some kind of fan setup.

Crazy idea.......

[octanemaestro]

Surely there's an airplane piston engine that can be dialed up to 6,000 RPM, somewhere. I'm very curious about this. Many experimental aircraft have used modified dual-plug dual ignition redundant VW flat engines for the longest time. I realize that's going the other direction -- i.e., high RPM to low RPM from car to aircraft, not aircraft to car -- but on the surface this just doesn't seem like a crazy idea to me. It was crazy to make a jet powered Chrysler but they did that anyway at headquarters in Detroit, and this would be a far more modest target for an individual garage.

[JackMan]

Conti engine just won't work in a car. Those engines are made to be cooled with forced air -- period. Never mind the issue of the low rpmz.

[HorstP]

are you at all aware of the displacement of an aircraft engine? A common 6 cylinder engine would be called O-540. And the 540 stands for the displacement in cubic inches....

[GH85Carrera]

Nothing is impossible, but it would be a huge waste of money and time. The RPM issues is the big first issue to overcome. Then cooling is the other. You can build a monster 911 engine that will work great for way less money than re-inventing the wheel. And have you priced an airplane engine?

We just swapped the engine on our 206 non turbo and it was way way way more than my 911 engine rebuild cost. Way more expensive.

[octanemaestro]

Originally Posted by HorstP

are you at all aware of the displacement of an aircraft engine? A common 6 cylinder engine would be called O-540. An the 540 stands for the displacement in cubic inches....

What...is that some kind of knowledge test?

I don't know what you are you trying to convey by writing, am I "even" aware. I suppose that's some kind of thinly veiled insult. There is no place for that here, a community focused on mutual help and sharing of knowledge. How is the displacement relevant and the horsepower is not? In fact, how is the displacement relevant at all?

[PatrickS]

A JATO unit would be more fun

[tobluforu]

Anything is possible, just don't get to close to the back of this one.
https://www.youtube.com/watch?v=yGeSIM_8BHY

[aschen]

I worked at continental motors for a summer as an intern. It was a fun experience. I think the motors arnt really suited to cars for alot of reasons. But with enough work Im sure you could make it work. I think the engines are significantly bigger, or at least alot longer than a Porsche flat 6. Each piston/cyl is around 1.5 L. I think a 4 cyl might have a better chance of fitting.

The engines are around 300 hp @ 1800 rpm so that is something ~ 600 ftlbs. Your gonna need a 930 transmission for sure.

I think a more interesting challenge would be to get a porsche to run on a radial engine. Lemons racing allows and unlimited budget for radial powered cars.

[stephen1070]

Everyone should own an airplane engine powered car!

Bob Petersen Engineering | Custom vintage coachbuilt cars | Devon UK

[cgarr]

hell ya do it!!

https://youtu.be/FSzGZh__BuM

[Jim2]

Though somewhat neck in neck price wise the Porsche (auto) engine has a slight advantage to certified aircraft engines, not to mention all the engineering it would take. Oh, and there ain't no bellhousing attachment on the drive end of an aircraft engine!

[nota]

my dad scratch built a aircraft motor powered car in the 40's
based on his war work on the B29 front nose wheels
that could move the B29 by hydraulic motors

the car used a hydraulic pump on the aircraft engine
and driven motors in the wheels
it had no gears
no brakes but had accumulators for regen-braking
no driveshaft

Ford hired him to develop the systems



tank accumulator on top pipe and valves lower bit


motor in car


space frame before motor mounted

[Flieger]

Why? A turbo would get you the same power with less trouble. It can be done but aircraft engines are designed for very different duty than car engines so it will be a lot of work and at the end of the day you have taken an overhead cam air-cooled flat 6 and replaced it with a pushrod air-cooled flat 6. Not that different and certainly no more exotic. Is the 540 cubic inches worth the hassle?

[HorstP]

Originally Posted by octanemaestro

What...is that some kind of knowledge test?

I don't know what you are you trying to convey by writing, am I "even" aware. I suppose that's some kind of thinly veiled insult. There is no place for that here, a community focused on mutual help and sharing of knowledge. How is the displacement relevant and the horsepower is not? In fact, how is the displacement relevant at all?

There was no intention to insult you. But the idea is so far from being practical that I did throw in that argument. I had hoped that pointing out the fact that a 6 cylinder aircraft engine has in pretty much all cases more than 7 liters displacement is already a hint that it has no practical value to discuss this. Displacement is of course relevant as it determines how big and heavy such an engine is.

Displacement aside, the biggest topic, as already raised, is the fact that a bigger aircraft engine is designed to run at a fixed rpm setting. Smaller, 4 cylinder engines coupled to fixed props do run at different rpms, but bigger engines, specifically the 6 cylinder ones, are in almost all cases running with a constant speed prop, so rpm stays constant but the propeller is adjusted. A typical IO-540 motor runs at around 2200 rpms and produces about 225 hp as rough indication. (I stands for injected, O for opposed, H would stand for the use in a helicopter).

Another indication on the shear size of piston and cylinders: an aircraft engine cannot /should not simply turned off. After landing, it needs to run typically another 2-3 minutes to cool down. Once the cylinder head temperature has dropped and stabilized, only then it will be shut off.

The fan required on an air-cooled aircraft engine is quite bigger than the fan of a 911 engine, it is a big piece of metal. Fixed wing aircraft don't have a fan as they just push air through the cowling but helicopter versions do need the fan.

And no aircraft engine will withstand 6.000 rpms. One of the higher turning engines, a HIO-320 runs at 3.200 rpms. We had somebody overrev it by 10% for 30 minutes, engine was toast after that. Almost all valves bend.

So bottom line, forget it...

[Trackrash]

If you want huge horse power go with a gas turbine. 6000 HP. Not much bigger than a piston motor.
https://en.wikipedia.org/wiki/Lycoming_T55

[HorstP]

as a matter of fact, a turbine with comparable HP is much lighter than a piston engine. I can lift a turbine producing 400hp. But yet again, same problem, they run at constant output rpms (the gas producer runs a variable rpms depending on the load)

[gtc]

Originally Posted by Trackrash

If you want huge horse power go with a gas turbine. 6000 HP. Not much bigger than a piston motor.
https://en.wikipedia.org/wiki/Lycoming_T55

I dunno. I think you would have to upgrade to a G50, or at least 108mm CVs. Sounds like a hassle.

[winders]

Read post #2 again........../thread