# Steps to scratch build a VW

Discussion in 'Hangar Flying' started by Little Scrapper, Aug 13, 2019.

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1. Aug 22, 2019

### Little Scrapper

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Lot's of posts! Excellent.

I have an idea, how about an interactive VW engine build. I'll flip the bill, everyone makes comments and suggestions, some will learn and some will teach, we all seem to get along and are mature because we all have the same goal.

If someone is able we can create a timeline list and just work through the list. I'll take the list and produce a 2 min movie per list item. In the end we have a motor that runs on a stand and everyone has skin in the game even if the only thing you do is watch.

If we're luck we may even help aviation. Like I said, I'll spend what it takes. Let's have fun.

On vacation this week I've been doing some reflection and decided to shut down a part of my business that will bring me from 70 hours a week to about 40/50.

I'm a 100% in on this. Life is too short not to do it.

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2. Aug 22, 2019

### karmarepair

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Back to heads. http://vwparts.aircooled.net/OEM-VW-35-x-32mm-Dual-Port-Cylinder-Head-EACH-p/oem-cylinder-head.htm is what I've got for my un-completed engine. ASSUME you'll have to take care of the casting flash your own self. Drag racers need big head to run big displacement engines at HIGH RPM. At the LOW RPM we run at, we do not need that, even with big jugs and big strokes. Big valves are usually single piece stainless steel, and unless they are VERY high quality and cost, they tend to stretch and open up and burn. I'm not aware of a source for NEW single port heads.

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3. Aug 22, 2019

### Vigilant1

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Little Scrapper,
That sounds great, but ambitious! And, I expect some ruffled feathers along the way.
The GPAS engine build manual might be a convenient starting point for a framework of the order of processes, I think. Discussion here would result in variations from that, and it would be good to make each choice explicit so it is easy to understand what was done and why.
As we know, the VW engine is very adaptable, suitable for everything from 40HP to 75 HP, can turn a prop from either end, can have a starter and electrical system or none. all kinds of ignition and fuel induction options, etc. Every choice made will be wrong/non-optimum for some other users, so the videos will be useful to some people and not others.

Last edited: Aug 22, 2019
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4. Aug 22, 2019

### Little Scrapper

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Sounds good to me.

5. Aug 22, 2019

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6. Aug 22, 2019

### blane.c

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7. Aug 22, 2019

### Vigilant1

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Wow, 360% of the price of Mahle pistons. They must be very special.

Maybe a glob of JB Weld on the top of a flat-topped piston would do the trick

8. Aug 22, 2019

### blane.c

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Food in the trough.

9. Aug 22, 2019

### Pops

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Removing part of the bellhousing when using a flywheel drive VW engine. Removed 1/2 pound of metal. Left a smaller flange for strength.
Notice that the case is welded behind #3 cylinder and bored for 94's or heavy wall 92 mm cylinders. The case has been clearanced for a stroker crank if wanted. Used the powered hacksaw for 95% of the cutting and the rest with the handheld hacksaw. Then cleaned up with a air grinder with a drum bit.

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10. Aug 23, 2019

### blane.c

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The "squish" pistons will allow the use of longer rods or reduce the compression ratio, which may be advantageous to some and depending on what combinations you are putting together could be less expensive than other options.

11. Aug 23, 2019

### Vigilant1

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Sorry, I was just being a wisacre. I'm sure some folks might like to have them. $650 for a set of pistons is a lot when folks are used to paying$180 for a set of good pistons. \$470 extra isn't much in the airplane world, but it is a lot in the VW airplane engine world.

Last edited: Aug 23, 2019
12. Aug 23, 2019

### blane.c

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The shop Pops uses? http://keithsautoparts.com/

Interesting variety of build options http://onex-svingenb.blogspot.com/p/vw-engines.html

Accessory weights http://www.greatplainsas.com/scaccesslbs.html

Hoovers blog page on the oil system modifications and other things towards bottom of page http://bobhooversblog.blogspot.com/...-max=2007-06-01T00:00:00-07:00&max-results=10

I balanced engines in the back of this shop the summer of 1976, if you got your HD or Triumph balanced in Northern California back then I did it cause this was the shop everyone sent there stuff to. But mostly I balanced small block V-8". https://www.yelp.com/biz/horse-power-by-gerolamy-carmichael

Drilled for oil magnesium engine case https://www.scatvw.com/engine-cases/as41-dual-relief/ Split Port Heads https://www.scatvw.com/cylinder-heads/split-port/ Case Savers and Case Studs https://www.scatvw.com/engine-cases/accessories/ Dry/Wet sump https://www.scatvw.com/engine-cases/drywet-sump-accessories/

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13. Aug 23, 2019

### Little Scrapper

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Because I'm close to MOFOCO it probably would be smart to use them or buy parts from them because of shipping. I'm in Milwaukee once every two weeks at a minimum because of a wholesale supplier I use for my plumbing business so stopping at MOFOCO would be effortless.

14. Aug 23, 2019

### don january

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Talking about steps to home build VW Engine for flight I noticed most if not all is of the type 1-2 focused much on the 1600 conversion to 1835 cc. There is info about the type 3-4 on the net for aircraft use. First step for me was to look around the neighborhood and see were there was some engines laying around such as a Melro spray coupe or a wrecked Beetle. 2nd step was to get one home and take it totally apart. I looked over the condition of the stock jugs /rods/ pistons/heads. In my case I asked just how far do I want to go with new parts and of what supplier. After many hours of reading info I believe that "stock" parts was the way for me. The first engine I did with Bob Hoover mods for cooling and balancing rods and pistons was tested in my trike and two years later still going strong. I guess the point I'm trying to make is see whats close by and think hard on how far you want to take the build. I'm glad I just started with a plain Jane 1600cc and got my hands dirty. Once you do one I think confidence level goes up ten fold for the next. FWIW

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15. Aug 23, 2019

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It sounds like you would be in pretty good hands there. They should be able to get you everything you need except the aviation-specific bits.

16. Aug 23, 2019

### 12notes

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If you want to trade some money for weight, a 7ah LiFePO4 battery weights a little over two pounds, and LiFePO4 doesn't catch on fire like lithium ion, and can be charged with a standard lead acid battery charger.

https://www.ebay.com/itm/12-V-7-Ah-...y-SLA-Replacement-Dakota-Lithium/222615221794

17. Aug 23, 2019

### Vigilant1

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Mofoco sold heads to Sonex, so they know their equipment has sometimes been used for aircraft. Still, they take steps to protect themselves legally (e.g. I'm not sure, but I don't think the Mofoco heads sold through Sonex still said "Mofoco" on them). So, if you have discussions with them,you may need to sneak up on this topic ("I have this friend . . ." or "I'm building an airboat . . ."). Some companies flat out will not sell directly to consumers who are using their products for aircraft.
I'm not a Mofoco fan based on the casting quality of the heads in my plane, but maybe things have changed. Kinda doubt it, though.

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18. Aug 23, 2019

### karmarepair

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19. Aug 23, 2019

### dmar836

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I cant speak for the OP but he is building a V-Witt. I can speak for myself as I am too. Doesn’t need a starter, alternator, electric avionics, or a battery. If I may very loosely paraphrase Tony Bingelis, “Cumulative ‘upgrades’ is how turds get built.”
Dave

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20. Aug 23, 2019

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