VW Heads for Aircraft - Billet

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Joined
Dec 25, 2018
Messages
20
Location
Prescott Valley
My Revmaster manual has a clean and accurate solution. Drill two perpendicular holes in the boss for the cylinder head nut closest to the exhaust valve. One of the holes should be just large enough to accept the wire from the thermocouple after you remove the ring. The second hole is tapped for a small set screw to secure the wire. At this location, Revmaster recommends temps of 350-375 for cruise and a climb limit of 450. Once installed, you won't have to bother it unless you remove your cylinder head or the entire engine. You can change plugs and torque heads without fear.
 

rmeyers

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Joined
Dec 20, 2013
Messages
77
Location
Southern Illinois
Update on progress. Even though I haven't posted in a couple of weeks, development is ongoing. Actually, going very well.

1. All of the physical parameters required to make a real head have been identified (hopefully!) and integrated into the design. It's a little hard to explain so I'll use an example. The head bolt/studs location is fixed because we are trying to make a new head for an existing engine. It therefore follows that the studs need to have nuts and washers on them. This means that they must be accessible by the engine assembler. Then the nuts must allow access to, at least, a box end wrench, preferably a socket. The socket is preferable because it is easier to use a torque wrench on. With the IN port design that I prefer, this means that the intake manifold mating surface is cut at an oblique angle. This results in a highly elliptical intake opening. The result of all this is that the head will be supplied with an adapter that is installed after the head is torqued down. Sounds complicated but the adapter is really only a small wedge shaped piece of aluminum held on with 2 screws.
 

rmeyers

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Joined
Dec 20, 2013
Messages
77
Location
Southern Illinois
OK somehow I just posted that before I was done!

I was going to say that all of the above is just one example of trying to make everything fit on an existing engine.

2. I have managed to make Mastercam agree to machine all of the features that I have designed. Not trivial. Mastercam is arguably the most powerful CAM product in existence, it is also arguably the most difficult to use. If the verification and backplotting in Mastercam show that it can be machined, there is a 99% probability that it will work. That is not to say that there won't be tweaking to the machining parameters, there will be. Example, finding the right feed and speed for the fin sawing that won't chatter and will leave a nice surface finish.

There are still many details yet to decide on.

I'll post more in a little while.
 

rmeyers

Well-Known Member
Joined
Dec 20, 2013
Messages
77
Location
Southern Illinois
Don't know if this will give you enough room.........?
Porsche style head nuts are available so the bore for the head stud nuts need only be large enough for the 10mm hex. The nut and washer can slide out the side.
View attachment 124624
What a great find! You know, I took the engine apart in my old 911 once and don't remember those. I really feel dumb forgetting those. Thanks again.
 
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