# Light Weight VW

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#### Pops

##### Well-Known Member
Log Member
Are there still some magnesium VW blocks (I think it was the blocks) out there? That might help.

Are the Verner engines any good? The 3 cylinder radial seems suitable. 34 continuous hp at 2200 rpm, according to them. I guess it might be harder to find parts than for a VW.

All factory VW Type 1 blocks are magnesium. There are some after market aluminum Type 1 blocks that weights 17 pounds heavier.

#### Pops

##### Well-Known Member
Log Member
Just curious, what would happen if you drilled holes through the cooling fins and fluted the edges? It would remove a little bit of weight and give the fins more radiating area.
Sand blasting the cooling fins helps with the cooling by adding more surface area.

#### Pops

##### Well-Known Member
Log Member
A 32 hp 1/2 VW can be built down to about 87 lbs. Would that work for your application ?

#### BBerson

##### Light Plane Philosopher
HBA Supporter
A 32 hp 1/2 VW can be built down to about 87 lbs. Would that work for your application ?
Yes. But that also takes a bunch of modification. I would rather have a smooth four cylinder of similar weight.
The crankshaft Casler uses is heavily modified and welded. I figure welding a new crank from scratch might be as much work. Drilling the existing VW crank isn't possible because the pins overlap.

#### Pops

##### Well-Known Member
Log Member
Yes. But that also takes a bunch of modification. I would rather have a smooth four cylinder of similar weight.
The crankshaft Casler uses is heavily modified and welded. I figure welding a new crank from scratch might be as much work. Drilling the existing VW crank isn't possible because the pins overlap.
You are correct. Building a cut case 1/2 VW engine is a lot of modification. I have built one. Cut the crank, welded the weights that I bought from Casler, etc. I would never built another, I would buy one built by Scott Casler and be happy. Considering all the machine work and time, Scott's engines are a good buy.

#### Aerowerx

##### Well-Known Member
Would a surplus 4A032 work?

From this web site:

The 4A032 is a four cylinder, horizontally opposed, air cooled engine. It has a displacement of 32 cubic inches which is about 500cc which in turn is about a third the size of a 40 horse power VolksWagen engine of the mid 60s.

New engines that have come out of military storage and good used engines are available on the supplus market. A similar two cylinder 42 cubic inch engine and a 4 cylinder 84 cubic inch engines are also available. There is also a 53 cubic inch opposed 4 that was used on the M274 Military Mule vehicle that I am aware of but have not seen for sale. From its pictures this engine looks like a very nice engine.
Keep in mind that the specs you will find on this are for the military. Mil Spec is 6hp, but it is 32 cu so you might get 12-15hp. Stock weight is 110 lb, but there is a lot of dead weight you could remove.

Saturn Surplus has them for $749.95. #### litemite ##### Active Member About the full VW on the Hummel. Teds words to me was he had taken an angle grinder to he crank "to make it look more like an aircraft crank". He did say it was very time consuming. He is a retired "shop teacher" and lives in Arizona. I can well imagine that he had quite a time with density altitude in the Phoenix area, and that was his drive to move from the 1/2 VW to the full engine. I, myself, am building a WindWagon but using Hummel plans to do the mechanical mods that Morry did to make the HummelBird. Al #### delta ##### Well-Known Member I got kind of excited the other day when these folks said the case they make is 18lbs lighter than an aluminum one. I'm not sure if it's as light as a magnesium one though. They've got some reasonably priced engine kits and long blocks in my opinion. They don't talk much about cam grinds but it seems they could fix a person up with just about any combo you wanted. http://www.scatvw.com/long-block-engine/ #### TFF ##### Well-Known Member Airplane cranks are hollow for constant speed props. They stopped making solid mostly to stop making two different cranks. #### Pops ##### Well-Known Member Log Member I got kind of excited the other day when these folks said the case they make is 18lbs lighter than an aluminum one. I'm not sure if it's as light as a magnesium one though. They've got some reasonably priced engine kits and long blocks in my opinion. They don't talk much about cam grinds but it seems they could fix a person up with just about any combo you wanted. http://www.scatvw.com/long-block-engine/ That is a magnesium case engine. What you see in the picture in the ad will weigh 116 lbs. Very had to beat the stock cam in the type 1 VW engine when using a straight drive prop. They list 1.25 ratio rocker arms. Not good for a straight drive aero VW engine. It will cost you HP below 3000/3200 rpm. In building a straight drive VW engine, you are building for torque at prop speeds NOT an auto high rpm hotrod engine. They also list light weight cam lifter, also not needed in a VW Aero engine. Same for heavy valve springs. Last edited: #### BBerson ##### Light Plane Philosopher HBA Supporter Would a surplus 4A032 work? From this web site: Keep in mind that the specs you will find on this are for the military. Mil Spec is 6hp, but it is 32 cu so you might get 12-15hp. Stock weight is 110 lb, but there is a lot of dead weight you could remove. Saturn Surplus has them for$749.95.
No. The 84 cu.in. would work but needs to be lighter also.
I think the VW is more supported.

#### BBerson

##### Light Plane Philosopher
HBA Supporter
Airplane cranks are hollow for constant speed props. They stopped making solid mostly to stop making two different cranks.
I was referring to the 1" bored lightening holes in the main shaft and crank pins.

#### TFF

##### Well-Known Member
Yep they stopped that too

#### BBerson

##### Light Plane Philosopher
HBA Supporter
A solid crank is cheaper. But a larger tubular crank is much stronger for the same weight.

#### Pops

##### Well-Known Member
Log Member
This is a Teledyne engine in Kevin's Mini-Max. Kevin is an old friend of mine at a field about 50 miles south of me. He put over a thousand hours on that MM airframe with a 1/2 VW and then put the Teledyne engine on to see how it would fly the MM. Nice little engine. Love his oil cooler.

https://www.youtube.com/watch?v=cj0hdymXfOg

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#### BBerson

##### Light Plane Philosopher
HBA Supporter
The climb angle was shallow, but not bad for 32cu.in. (525cc)
Are you sure that was only 32 cu.in.? (Maybe 42?)
My Honda V-twin is 40.8 cu.in. (670 c.c.)

#### Armilite

##### Well-Known Member
I have weighed a 1200cc, 40 hp, a 1600 cc, and a 1835 and 1915 engine and they all weighted 116 lbs for the short block. Never going to remove 16 lbs so would have to develop more HP.

2 pounds per hp could be done with a 2180 no-electric of 75 HP. Its just 2 lbs heaver than my 1835cc 60 HP. So I could change my 1835 to a 2180 and have a firewall forward weight of 143 lbs @ 75HP. Then that blows a hole in my 3 gph @ 80 mph cruise ( that is 26.6 mpg)
But I don't want 75hp.
I really just want 30hp in a low rpm smooth running four cylinder. A VW at 2100 rpm is really smooth. Much smoother than a A-65
I think I can shoehorn a 100 pound VW into and ultralight. 100 pounds plus 154 pounds airframe = 254 pounds
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I know this is an older post, but Why don't you just build a Half VW Big Bore using the Best Light Weight Racing Parts if you only need 30hp? Any Engine can be Balanced to run Smooth. If you use Ecotrons EFI or Meagsquirt EFI you can have a better Starting, Smoother running Engine with a better GPH. There was a 2 Cylinder VW Type Engine made in I think Brazil or Aregentia also. Maneesium Case's are lighter than Aluminium Case's. There are VW Engines & Parts 3D Modeled on the Web Free to download, you could take the Spec's off and make a Custom Billet Case that Bolts together.

But a Rotax 2 Stroke, 277 or 377 built right with all the Engine Mods(Coatings and a Tuned Pipe) out today is still your Cheapest and Lightest Option for a Part 103 Ultralight. I just saw a Rotax 377 Single Ignition with Gear Drive for \$800 on Craigslist in Texas the other day. A Rotax 277UL/377UL is the same as a Skidoo 277 & 377/380 made up to around 2008. Almost all Skidoo 2 Stroke Engines 93+ have Provision 8 Case's. Only the (277, 380F, 440F Till 2008), (503F Till 2003) were made into the 2000's.

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#### Armilite

##### Well-Known Member
The climb angle was shallow, but not bad for 32cu.in. (525cc)
Are you sure that was only 32 cu.in.? (Maybe 42?)
My Honda V-twin is 40.8 cu.in. (670 c.c.)
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They made a 4 Cylinder 084(45hp for plane use at a higher rpm than Stock, was rated 20hp at 10,000ft) an 042 4 Cylinder about half the HP so probably 21-22HP for plane use, an a 032 probably about 12-14hp, all of these Miliatry Genarator Engines are HP rated at 10,000ft. Only the 084 has ever been Dynoed that I know of making 45-46hp but at Higher than Stock rpms. The 084 is to heavy for 99.9% of the Part 103's out there. There 1000+hr Engines if you keep the rpms down for what they were designed for. Only the 084 has had many Mods done to it by a guy named Less Smute I think and he died a few years ago I think. If I remember correctly these engines had weak Rods & Rod Bolts if you try to push them to hard over the Stock rpms.

Per the Peak Flow/HP Calc at 90%: http://www.mk5cortinaestate.co.uk/calculator3.php
32ci at 3300rpms = 18hp
42ci at 3300rpms = 24hp
84ci at 3300rpms = 48hp

32ci at 3600rpms = 20hp
42ci at 3600rpms = 26hp
84ci at 3600rpms = 53hp

Per the Peak Flow/HP Calc at 100%: http://www.mk5cortinaestate.co.uk/calculator3.php
32ci at 3300rpms = 20hp
42ci at 3300rpms = 27hp
84ci at 3300rpms = 53hp

32ci at 3600rpms = 22hp
42ci at 3600rpms = 29hp
84ci at 3600rpms = 58hp

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#### Armilite

##### Well-Known Member
What specs would you change on this 1.2L Engine?

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#### Armilite

##### Well-Known Member
Some Stock VW CAM SPECS.

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