# Steps to scratch build a VW

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

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1. Aug 29, 2019

### Little Scrapper

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As far as other VW aviation companies? Well, after the entire discussion I came to the conclusion they are all using Chinese parts. Roy did NOT tell me that, this is simply my opinion after our long conversation. Except for the case, which, as I discussed is the AS41 cast in Brazil and machined in Brazil.

Next subject.....

2. Aug 29, 2019

### Little Scrapper

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Oops. Edit. I found a note I made.

Sonex heads come from CB Performance which are from Autolinea in Brazil. My mistake.

3. Aug 29, 2019

### Bill-Higdon

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4. Aug 29, 2019

### Bill-Higdon

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I'll get some pictures & info on the number of engines ran through EAA 292's test stand. It was used to a lot of development on the engines for the "Noon Patrol", the waterboxer on the flying DH2 and a host others. Little Scrapper may want to build something along the line of Whatley's test stand documented in April 1982 Sport Aviation but out of metal.

5. Aug 29, 2019

### Vigilant1

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You may have more recent info than I do, but as of a month or so ago Sonex was sourcing their heads from EMPI. Some EMPI parts are good, some are less good. I've heard one report of a builder that was unhappy with the EMPI heads--the valves leaked on a brand new head.

6. Aug 29, 2019

### Little Scrapper

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Ok. There's a bunch of random notes but nothing earth shattering so I'll not waste anymore time. The only thing left to talk about was our discussion on heads.

Many many years ago Roy's dad, the founder of MOFOCO spent about $500,000 to build casting molds for a head that cooled better and flowed better. They are cast in Wisconsin, machined 2 at a time at MOFOCO and all the parts that go inside them are 100% American made. You can see the old OEM VW head next to the new MOFOCO head. Zoom in and check it out. I looked over the heads and the castings were flawless. They were beautiful. Do we need these for airplanes? I don't know, I'm not knowledgeable enough to know that because I'm still learning. But here's the good news, Roy has factory German heads available. So that's cool. That's it. That's all I got. I have him my card and made a friend. I will be back and Roy said he'll walk me through the process or answer questions. It turned in to a hell of a good day for me. Here's a random photo and the last on my phone. Have a good evening. blane.c, Pops, dmar836 and 2 others like this. 7. Aug 29, 2019 ### Little Scrapper ### Little Scrapper #### Well-Known MemberHBA Supporter Joined: Jan 3, 2014 Messages: 5,352 Likes Received: 3,277 Location: Wisconsin It's possible. I don't know. 8. Aug 29, 2019 ### Vigilant1 ### Vigilant1 #### Well-Known MemberHBA Supporter Joined: Jan 24, 2011 Messages: 3,909 Likes Received: 1,721 Location: US Thanks, Scrapper, for the field report. It sounds like a good time. Times have changed in some ways, not others. All your pictures could have been taken in 1978 and everything would have looked just the same--except there would have been at least one ashtray in every picture, and a few spicy calendars. Thanks again. dmar836 and Little Scrapper like this. 9. Aug 29, 2019 ### fly2kads ### fly2kads #### Well-Known MemberHBA Supporter Joined: Jan 2, 2010 Messages: 1,450 Likes Received: 526 Location: Justin, TX Awesome! I really appreciate you taking the time to write up your notes for the rest of us. Sounds like a very worthwhile visit! Little Scrapper likes this. 10. Aug 29, 2019 ### Little Scrapper ### Little Scrapper #### Well-Known MemberHBA Supporter Joined: Jan 3, 2014 Messages: 5,352 Likes Received: 3,277 Location: Wisconsin Well guys, my only goal today was to get to the dam bottom of what case to use and why. Literally, that's it. I got so much more. It's pretty cool that we all know now the scoop on cases. It's no longer a mystery. I'll be back. Next time will be even more interesting. In the meantime, let's keep this active. Roy is placing another order after the holidays and my case will be on that order. Before no place the order I need to pick my CC size.....which I haven't. Pops and akwrencher like this. 11. Aug 29, 2019 ### AdrianS ### AdrianS #### Well-Known Member Joined: Jul 5, 2014 Messages: 339 Likes Received: 194 Location: Australia Thanks for all that interesting info. Re cam grinds : Has anyone compared the cam profiles of the transporter/bus variants to the cars? I'd assume that trundling a fully-loaded transporter into a headwind down the highway would be closer to aircraft use. Did they have a torquier cam? 12. Aug 29, 2019 ### AJLiberatore ### AJLiberatore #### Well-Known Member Joined: Nov 27, 2011 Messages: 108 Likes Received: 22 Location: Canton MI Scrapper. Check out the Baffle with a slot on the OEM Head. That bit is something that the Late Bob Hoover recommended and the old school homebuilt project I am tangentially involved with has them as well. Mr Hoover noted they make a big difference, I am sure you will do your research on it! Little Scrapper and dmar836 like this. 13. Aug 29, 2019 ### 103 ### 103 #### Well-Known Member Joined: May 3, 2015 Messages: 107 Likes Received: 61 Location: Wauwatosa WI Ion my last visit a whole truck of german single ports was headed out to be cleaned. As Mike said the 040A heads are a work of art. Invest 1 hour removing flash between the cylinders and mine apear to run 30-40f lower than my old heads on the same plane. OEM single port would be my choice 1915 and under. #### Attached Files: • ###### 20190801_134838.jpg File size: 158.3 KB Views: 18 AJLiberatore and Little Scrapper like this. 14. Aug 29, 2019 ### dmar836 ### dmar836 #### Well-Known Member Joined: Jun 16, 2014 Messages: 97 Likes Received: 77 Location: KC Those little things like the baffles being omitted for more air flow are likely why there are those who say a VW is a 50/50 engine. Leave them off a continental it Lycoming and see how that works out. It’s funny how guys will “logically” armchair engineer that but will neglect cleaning the fins flashing. LS, Thanks for taking the time to record all of this. Awesome info for sure and encouragement that there are some who support aviation. Last edited: Aug 29, 2019 AJLiberatore and Little Scrapper like this. 15. Aug 29, 2019 ### Little Scrapper ### Little Scrapper #### Well-Known MemberHBA Supporter Joined: Jan 3, 2014 Messages: 5,352 Likes Received: 3,277 Location: Wisconsin In prior posts it seemed like mentioning aviation around VW guys was kinda forbidden but I'm not sure it's so bad. Maybe on forums like the Samba it is but the companies that supply and build seem to embrace it fine, at least that's what I've learned at this point in my research. As far as the Samba, those are just internet strangers that don't really matter to any of us. I was really concerned about this going in to MOFOCO because of all the posts about VW people not liking aviation. I'm really happy that wasn't true. It's so nice to have a local builder to lean on. I'm thinking I'll go with the AS41 case from MOFOCO and have them supply me with German heads, German rods and a German crank. That seems to be a pretty smart move. Still thinking through the CC part. 16. Aug 29, 2019 ### 103 ### 103 #### Well-Known Member Joined: May 3, 2015 Messages: 107 Likes Received: 61 Location: Wauwatosa WI Brasil As41 case and All german stock 1915 engine will be the most bang for the buck. I highly recomend the custom 6.8 lb flywheel from GP as well as the flywheel drive hub and dynamo. Mofoco can support all your core enginenparts needs just fine. For those of us in SE Wisconsin it is real easy to visit the shop for new wear parts and gaskets. I bought a dozen cylinder head tin gaskets for$12 I replace them everytime I check the valve clearances.

At Roy's recomendation I upgraded mine to the newer Oring groove flywheel. Currenly setting the endplay.

Matt

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17. Aug 29, 2019

### dmar836

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I have to warn again to avoid mission creep here. “Bang for the buck” has been said a lot but that is not the mission. Let’s be direct. A plane this size and weight with a cockpit this claustrophobic has no need nor structural strength for more bang or weight. The OP may wish to add extra ccs, install a charging system and all that goes with it, etc. but, regardless of the perceived benefits, all that is mission creep. This same creep will undoubtedly occur when we begin talking fuel delivery. Just a little more security or reliability with only a little extra weight. Then might as well add some light weight tip lights and a beacon in case you get caught out after dark. “LEDs weigh nothing anymore so...” and on and on.
This is a stripped down racer. “Simplify, then add lightness”
In my case I’m now of the mindset that more ccs is the last thing I want!

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18. Aug 29, 2019

### Little Scrapper

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I'm leaning heavily towards the standard 1600. Look for performance in other places seems like a fun endeavor in itself.

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19. Aug 29, 2019

### lakeracer69

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Mike,
Thank you for doing the leg work and reporting it back here. It brings a little more clarity to a muddy subject.
Looking forward to the next installment, when you get to it. I am happy to see some of the case confusion sorted out for me too.

John H. in NH

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20. Aug 29, 2019

### Pops

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When I quit building VW engines as a side business along with selling VW cars only in 1978, I had a building for my engine building shop and gave away 3 pickup truck loads of engine parts. Case, cranks, rods , heads, etc, etc, All German parts, enough to build maybe 20 complete engines. I missed some of the parts and I still have 2 German cranks, about 6 heads and a couple cases, couple dozen rods, several cam, etc, etc.

I worked for VW or America for many years, ( They send me a retirement check ) and the quality control was better than the quality control in the German made Rabbits. VW of Germany even said so. I worked closed to a year installing all the computer measuring equipment that measured the body panels in the Quality Control Dept. Parts were rejected that the eye could not detect in the panels. Quality Control also assembled complete Rabbit bodies to make sure everything was perfect.

BTW-- We also built 100 aluminum Rabbit bodies , never knew what happen to them.

So don't be surprised to learn that the German made VW engine parts are the best on the market.
Great company to work for.

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