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The 100HP VW--Reliable? Practical?

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TFF

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You dont tell the FAA it can do anything more; max is max. If there is a reserve, it has to be in the hidden notebook between your ears.
 

Vigilant1

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I am no fan of the old KDF Wagen or its engine, would rather search for an automotive, motorcycle or “recreational” engine that have 100hp at peak toque that could be used/converted.
One very big factor (in my opinion) that is in favor of the VW is the large experience base of folks running them in airplanes. They've suffered and overcome the crank failures , bearing failures, lubrication issues, the cooling limits are well understood, the parts that need inspection are well documented as are the sign of trouble. In many ways, this is more effective than any corporate-sponsored development program.

But, I have thought a lot about a motorcycle adaptation. That BMW R1200 with the Take-Off PSRU and other bits is very tempting. Sub-200 lbs, would probably make 100 HP for takeoff, and make 80 HP all day. I think.
 

Vigilant1

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You dont tell the FAA it can do anything more; max is max. If there is a reserve, it has to be in the hidden notebook between your ears.
As the engine manufacturer I could placard (or enter in the POH) it for whatever is reasonable. But clearly (and honestly), "max continuous" is not the same as "max available" for many engines.
 
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autoreply

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It can be done, at altitude. The US regulation says:
Ah, never realized it was IAS, not TAS. Put on some oxygen, block your altimeter at 9999 ft and you could do 200 kts :gig:
One very big factor (in my opinion) that is in favor of the VW is the large experience base of folks running them in airplanes.
Indeed. It's the only engine I'd ever consider to fly behind that's not a "native" aircraft engines.
But, I have thought a lot about a motorcycle adaptation. That BMW R1200 with the Take-Off PSRU and other bits is very tempting. Sub-200 lbs, would probably make 100 HP for takeoff, and make 80 HP all day. I think.
If you can solve the canbus issues (requiring a massive load of fake sensors) or replace it by another injection/ignition system, it'd make a pretty good engine. Better yes, hundreds are flying in Europe.
As the engine manufacturer I could placard (or enter in the POH) it for whatever is reasonable.
Would you not run into problems if you'd limit it to say 50% power with regards to the LSA "classification" and the FAA?
 

StarJar

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I have seen what I would guess is a 80hp Sonex takeoff solo a couple of times. Not a rocket; closer to a C150. I was surprised.
A Sonex is not intended to compare with a C-150 on take-off. If it equalls a 150 on takeoff, even solo. That actually says alot for a plane with less horsepower, and less wing area.
 
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Vigilant1

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Ah, never realized it was IAS, not TAS. Put on some oxygen, block your altimeter at 9999 ft and you could do 200 kts :gig:
You're not alone. This issue comes up all the time in the Sonex "world". As far as cross-country flying goes, the Sonex isn't ideal (it's a little less stable than would be desirable for this kind of flying, along with the previously mentioned limits on payload), but in my book 170 MPH is good enough for the occasional trip. In actual testing the plane routinely gets 30+ MPG at these speeds which is impressive.
Sonex has been working on a turbo for their little Aerovee VW-derived engine. I think you can see what that might mean for cruise performance at 9000' MSL.

Would you not run into problems if you'd limit it to say 50% power with regards to the LSA "classification" and the FAA?
I think it would be a subjective call, between the builder and the DAR. They'd give you trouble if you came up with something unreasonable.
 

TFF

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Pound per HP the 80 hp sonex out powers the 150. I watched it take off again today and it still is surprising how slow it climbs. 2 up and you better have some runway.
If max available will push the plane faster than the max speed at sea level, it better not be documented.
 

Vigilant1

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If max available will push the plane faster than the max speed at sea level, it better not be documented.
There are a few hundred of them flying now, I think the FAA is satisfied that everything is legitimate.
 

BBerson

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One very big factor (in my opinion) that is in favor of the VW is the large experience base of folks running them in airplanes. They've suffered and overcome the crank failures , bearing failures, lubrication issues, the cooling limits are well understood, the parts that need inspection are well documented as are the sign of trouble. In many ways, this is more effective than any corporate-sponsored development program.

.
There is no large VW experience base of folks running 100 hp in airplanes. This would be unproven and most likely pushing to failure.
How could an over boosted or over revved VW (130 cubic inch) equal a 200 cubic inch airplane engine (Cont. o-200) in reliability ?
 

Topaz

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There is no large VW experience base of folks running 100 hp in airplanes. This would be unproven and most likely pushing to failure.
How could an over boosted or over revved VW (130 cubic inch) equal a 200 cubic inch airplane engine (Cont. o-200) in reliability ?
Yes, I'm with you on this. There is extensive experience at 65hp (takeoff) and below, and a slowly growing base of evidence at the 70-75hp (takeoff) power level. I have no direct experience with 100hp VW variants, but I remember the Revmaster 100hp turbo variant from the 80's was reputed to be quite flaky and in need of very careful and disciplined maintenance and pilot usage. That engine alone was one of the driving factors in the development of the Q-200, which put an O-200 in the nose of the Q2 instead, with a modified canard as well. The Q2 had fairly marginal climb performance on a 65hp VW (the original design powerplant), especially at heavier loadings and the increased empty weights common with kitplanes.

As I mentioned earlier, Great Plains has a 105hp (takeoff) model, but they've achieved that through the time-honored tradition of punching the engine out to a larger displacement (2276cc, IIRC), and then giving it the custom-heads treatment and, I would guess, a pretty sizable oil cooler. Only resembles the original Type I at that point, and I've heard nothing about the engine's reliability in practice. However, Great Plains has a generally very good reputation, so if they're standing behind this engine, it may well do what they claim. But I imagine that the duration of takeoff power is a hard line that you do NOT exceed or mess with, lest your TBO drop significantly. Trying to push that takeoff-power-time further in any way seems to me to be asking for trouble.
 

BBerson

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I just checked the Great Planes website and found only 80hp maximum for type 1.
I think they had some type 4 in the past, but I did not see it now.
 

Vigilant1

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I just checked the Great Planes website and found only 80hp maximum for type 1.
I think they had some type 4 in the past, but I did not see it now.
The Type one with a PSRU they sell has a max output of 105 HP, but that's just for takeoff (it will produce 72 HP continuously) . It's a 2276cc engine, and I think the engine itself is largely unchanged from their direct drive 2276 cc engine (which produces 80HP for takeoff, 76HP continuously). The PSRU just allows higher RPMs (= more horsepower) while still driving a useful-sized prop. Here's a page from their web site, the catalog has more in-depth information.

There is no large VW experience base of folks running 100 hp in airplanes. This would be unproven and most likely pushing to failure.
How could an over boosted or over revved VW (130 cubic inch) equal a 200 cubic inch airplane engine (Cont. o-200) in reliability ?
Yes, right. I should have been clear in saying that I was talking about the commonly available VW-derived engines when talking about the experience of the "installed base". It won't run at 100 HP for hours on end like an O-200, and anything done to boost the little beasty to 100HP would put it in the "something not commonly done" area. But there are a lot of people flying them in draggy airplanes with these redrives, and they do get 100+ HP from them for the takeoff, so it's not unheard of.
 

BBerson

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I owned a Cessna 175 for a while. It had a gear drive and large prop. It certainly climbed better than a stock C-172 but used much more gas and cruised at a higher rpm( which I did not like)The Go-300 had more maintenance issues and obviously was somewhat less popular than the o-300.

Everything comes with some downside.
I think for your mission, a turbocharger would give the boost needed. But it certainly could blow the engine up.
So the only reliable plan is look for another larger engine if you really want 100-120 hp.
 

litespeed

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Not sure about the stock setup but valve issues can be solved with a injection of money.

Stellite seats and sodium filled stainless valves- should solve the heat issues for the valves and seats- would not expect any dropped valve heads or valve seats.

A proven combination from old twin cam Alfa engines.

How much are the valves- don't know.

Phil
 

Himat

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But, I have thought a lot about a motorcycle adaptation. That BMW R1200 with the Take-Off PSRU and other bits is very tempting. Sub-200 lbs, would probably make 100 HP for takeoff, and make 80 HP all day. I think.
If you can solve the canbus issues (requiring a massive load of fake sensors) or replace it by another injection/ignition system, it'd make a pretty good engine
I did a search on the internet on CANBUS and a few other different terms. It does look like canbus is an open and well documented standard. The quick search also pointed at some “gadgets” available to “free” developers. As canbus is a serial bus with telegrams from the sensors, no fake sensors are needed, just one computer that supply the telegrams. If BMW have not taken steps to make their system tamper proof this should not be a too difficult challenge.
 

autoreply

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I did a search on the internet on CANBUS and a few other different terms. It does look like canbus is an open and well documented standard. The quick search also pointed at some “gadgets” available to “free” developers. As canbus is a serial bus with telegrams from the sensors, no fake sensors are needed, just one computer that supply the telegrams. If BMW have not taken steps to make their system tamper proof this should not be a too difficult challenge.
Well, they have. Long story short, you replace the whole system, or you add all sensors, those are basically your options.
 

Himat

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Well, they have. Long story short, you replace the whole system, or you add all sensors, those are basically your options.
Ok, I do understand that BMW or anyone else do keep protocols and the like confidential, but I would be surprised if they have introduced encrypted sensor data and authentication of the sensors.

Anyway, here is a link about how to have a peek. http://bobodyne.com/web-docs/robots/MINI/CAN/MINI_CAN.pdf
A BMW motorcycle should not be that different as long as Mini cars are made by BMW.
 

Pops

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I fly behind a VW type 1, 1835, 60 HP, 7.5 CR. Zenith Carb, Slick Mag. No electics. 141 lbs firewall forward weight. Culver 60" X 26" prop, single port heads with stainless valves. Bob Hoover's HVX oil mods with a oil filter, oil cooler, and a hot oil box around the intake at the base of the carb ,( also cools the oil 20 deg). Great engine with lots of power. NO heating problem. Cruise- 80 mph, burning 3 gph at 2700 rpm. ( that's about 35HP). ROC- 1200+ at GW. TO-250'
Aircraft -- Fisher Super Koala Construction, but built to the dimentions of the Koala 202 to look like a Cub. EW- 450 lbs.
Perfect combination of airframe and engine.
 

Vigilant1

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I fly behind a VW type 1, 1835, 60 HP, 7.5 CR. Zenith Carb, Slick Mag. No electics. 141 lbs firewall forward weight. Culver 60" X 26" prop, single port heads with stainless valves. Bob Hoover's HVX oil mods with a oil filter, oil cooler, and a hot oil box around the intake at the base of the carb ,( also cools the oil 20 deg).
Pops,
Welcome to the board and thank you for the information. Have you got any additional information on the hot oil box at your carb? Is this an off-the-shelf item or an item you built?

Mark
 

Pops

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At first I was having a lot of carb ice and using the exhaust carb heat very often. I welded up a small box around the intake at the carb flange. No more carb ice and the engine runs stronger and smoother. With the long intakes the fuel charge was condencing into droplets and making the cylinders run lean and then rich when all the droplets went in the cylinder at one time. It also cools the oil 20 degs with a point and shot temp gage. They also wrap the intakes with aluminun tubing on the 1/2 VW for the same reason. Notice that Lyc has part of the intakes inside the oil pan. Pops



Pops,
Welcome to the board and thank you for the information. Have you got any additional information on the hot oil box at your carb? Is this an off-the-shelf item or an item you built?

Mark
 

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