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Steps to scratch build a VW

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TFF

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Go Corvair if you need a change. The Jabiru is small. Probably a better airplane engine than was the VW but does not solve your problem of cubic inches. 134cid.

Reverse the situation, you need to spin around a 70” prop give or take. Your engine needs to do this. 65 hp VW with a 64” prop would be on the unsafe side of low speed thrust. Surface area of your whole airplane is 50-75% more than a Sonex or Sonerai. You are dragging more airplane through the air on the same horsepower; it has to be applied different.

You are up against the engine paradox that every engine conversion problem has, your airplane and engine don’t match. The airplane wins every time, the engine doesn’t.

A Full VW would be perfect on a Legal Eagle built to Double Eagle strength, which is probably about the same anyway. A Legal Eagle that was about 300-350 lbs with the VW would be great. Maybe add a foot or two to the fuselage. That would be a cool.
 

103

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Empty weight of the Baby Ace is 575lbs, max gross is 950. That's almost exactly what my Sonerai II is. The A65 is 65 hp at 2300rpm. The GPAS 1835 will give you about that, albeit at a slight faster RPM.

I'd think that without a starter, a cut-down flywheel, and an Ed Sterba VW specific prop, you'd get close to specs as long as you kept the empty weight down. And, if you absolutely must have it, with the cut-down flywheel and a modified accessory case, you could run a stator type 20 amp alternator for something like the Trig transponder/ads-b set up with only a modest weight penalty.
While allot more work and maintenance the 86mm crank with chevy journals and 94mm jugs. Hand propped 2386CC 145CI Flywheel drive and distributor bleed down ignition with coil combiner to drive a single plug per cylinder like the corvair guys might just do the trick. Keep it down to 145lbs and sling a 62-64" prop. Dont plan on more than 45hp continuous and only about 64/70 for take off!
 
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Pops

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The Baby Ace is a high drag airframe, not so with the Sonerai. You have to have the right match for the engine, prop and airframe. Will not get it with the VW engine in a Baby Ace.
The SSSC with the 1835 cc , 60 HP engine has an EW of 485 lbs after going with the large tires, and new wings with 2-- 8 gal fuel tanks for long range flying. The EW was 450 lbs with the small 5" wheels and tires and wings with a 2 -- 4 gal tanks of fuel. The right prop is the Culver 60"x 26" for a ROC of 1200+ at 800 lbs and a cruise of 80 mph at 2650/2700 rpm. 120 sq' of wing area.
You can put the biggest VW engine in the Baby ace and not come close to that performance and will be having heating problems.
 
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Vigilant1

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Open cockpit, struts, large braced undercarriage-- the Baby Ace is cool, but draggy. It would probably be better off with an engine that can turn a long prop.
Maybe ask around among some folks who fly Baby Aces? I'm sure someone has put a VW Type 1 on one at some point.
Scrapper, you've been intrigued by the VW for awhile. Building one up is a low buck affair. If you are on the fence after gathering info, you could just build this engine for its own sake and see if you like how it flies. You could put it on something else later if it doesn't suit the Baby Ace.
 

Pops

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While allot more work and maintenance the 86mm crank with chevy journals and 94mm jugs. Hand propped 2386CC 145CI Flywheel drive and distributor bleed down ignition with coil combiner to drive a single plug per cylinder like the corvair guys might just do the trick. Keep it down to 145lbs and sling a 62-64" prop. Dont plan on more than 45hp continuous and only about 64/70 for take off!
Then the case is the weak point. Could go to the aluminum case but that is 17 lbs more and you are back to the start.
At cruise my VW engine is developing about 33 hp continuous. Burning 2.9/3.0 gph.
 

Pops

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Build a Cygnet for your VW engine and be happy.
 

TFF

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A Baby Ace would need a belt drive. It lasted about a week on the Pixi. It flew but it was not close to the same. Even though they kept the VW in the advertising, Paul P recommended the Continental option.

The bigger VWs are alway close to being grenades. Pushing every component. Over 1835 is just a stressed engine when you want lazy. Forcing issues when effortless is preferred.

Pops SSSC is the right idea. A little smaller and a little lighter.
 

Flyguyeddy

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Then the case is the weak point. Could go to the aluminum case but that is 17 lbs more and you are back to the start.
At cruise my VW engine is developing about 33 hp continuous. Burning 2.9/3.0 gph.
My wasser case converted to air cooled is 12 lb more than a mag caae and is a factory die cast vw block
 

Pops

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My wasser case converted to air cooled is 12 lb more than a mag caae and is a factory die cast vw block
I just weighed 2- Type 1 cases. 24 lbs and 4 ounces each. EMPI list their aluminum Type 1 case at 44 lbs. I have seen the difference listed at 17 pounds.
All stock VW long blocks from 1200 cc to 1835 cc weighs 116 lbs. That is a 1200cc, 1300cc, 1600 and a 1835cc long block. I have weighed each.
 

Little Scrapper

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Ok. Let’s rule this out for now although a VW is definitely in my future for the V-Witt.

What about a Model A like the Pietenpol?
 

Little Scrapper

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I thought about the Vernier but was thinking more budget minded. I’m not sure .what the HP requirements are but it might be fun to do a Model A or a A40.

I have a friend with two Continental that I can get, a 65 and a 85. I can certainly do that and I might but man I really want to do something unique and fun. A engine you don’t see commonly in a Baby Ace.
 

Pops

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Seen a Lyc- 290 on one :) Bet there was lead in the tail.
Friend of mine had the nicest Baby Ace I every saw. It would have been a show winner. Red and white in the Pitts scheme. Baby Ace kit company used the picture of it. Dallas Shell ( hanger 2 doors away), made the engine mounts, fuel tanks and Landing gears for the Baby Ace for the Kit company.
Cont-85 makes a good engine for one.
 

Little Scrapper

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Seen a Lyc- 290 on one :) Bet there was lead in the tail.
Friend of mine had the nicest Baby Ace I every saw. It would have been a show winner. Red and white in the Pitts scheme. Baby Ace kit company used the picture of it. Dallas Shell ( hanger 2 doors away), made the engine mounts, fuel tanks and Landing gears for the Baby Ace for the Kit company.
Cont-85 makes a good engine for one.
Yeah the 85 is definitely a win combination. Dealing with liquid cooled and a radiator isn’t my first choice but it might be cool. I don’t know, need to think on this. Over the years the Baby Ace has had a lot of different engines, especially early on, but the little Continentals are about as ideal as a person can get.
 

TFF

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Please, Oh, Please, Oh, Please stay on track. Think of the new project and source that package. Don’t start what if’s. Don’t change the Pepperoni Pizza in the oven to Mushroom. Make another Pizza. Later. You have made so many parts; it’s not like this is the last time.

The Piet compromises everything to put the A engine on it. It’s point is because poor depression people has no choice. The choice would never have been chosen under another circumstance. I have respect for the Piet. A friend built two. One with an A and one with a LeBlond radial. The A rarely gets flown. Too marginal. The Corvair Piets are much more flyable.

I can’t see anything but a Corvair or a Lycoming O-145 being worthy but still a performance loss. Yes an A-65 is not original except it’s a full finished flying winner. C-85 is winner winner chicken dinner.
 

simflyer

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You have to have the right match for the engine, prop and airframe. ... with the 1835 cc , 60 HP engine The right prop is the Culver 60"x 26" ... and a cruise of 80 mph at 2650/2700 rpm. 120 sq' of wing area.
If looking for simple solution to homebuilt VW and get torque/power at lowest rpm (up to 3000rpm), then use some of orig. CT block, with 74-76mm stroke + 88mm cylinders, with W100 camshaft, to not need rework block. You get cca 1850cc. Prop should be cca 162-165cm and pitch cca 90cm. Look on Sauer VW engines - they're getting power at lower rpms, than any other VW aircraft engines.
 

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Little Scrapper

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Please, Oh, Please, Oh, Please stay on track. Think of the new project and source that package. Don’t start what if’s. Don’t change the Pepperoni Pizza in the oven to Mushroom. Make another Pizza. Later. You have made so many parts; it’s not like this is the last time.

The Piet compromises everything to put the A engine on it. It’s point is because poor depression people has no choice. The choice would never have been chosen under another circumstance. I have respect for the Piet. A friend built two. One with an A and one with a LeBlond radial. The A rarely gets flown. Too marginal. The Corvair Piets are much more flyable.

I can’t see anything but a Corvair or a Lycoming O-145 being worthy but still a performance loss. Yes an A-65 is not original except it’s a full finished flying winner. C-85 is winner winner chicken dinner.
Alright now settle down!!!! Haha
 

Pops

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If looking for simple solution to homebuilt VW and get torque/power at lowest rpm (up to 3000rpm), then use some of orig. CT block, with 74-76mm stroke + 88mm cylinders, with W100 camshaft, to not need rework block. You get cca 1850cc. Prop should be cca 162-165cm and pitch cca 90cm. Look on Sauer VW engines - they're getting power at lower rpms, than any other VW aircraft engines.
To get the most bang for the buck, and the most reliablity for the HP. Stock German 69 mm crank. Single port heads for more torque below 3000 rpm over dual port heads, with 1 1/4" dia intake tubes , stock cam and 92 cylinders and pistons for 1835 cc. Balance with 7.55 CR.
 

Marc W

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Pops, is the 1-1/4" intake tube ID or OD?

Random thought: At my mile high airport, my 2180 makes about the same power as the 1835 does at sea level. Does that make it as reliable as an 1835?
 

cavelamb

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Not a good choice at all.

Look at the difference in propellers.
Continental A-65 vs VW
 
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