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    Second ignition for my VW engine

    Another alternative for a primary or secondary ignition is the GMC HEI system It consists of an electronic control module, a dual output coil or two, and crank position sensors. It is easy and low cost to position one sensor at zero degrees and the other at 28 deg BTDC then use a switch to...
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    Yet another VW power argument. Again.

    To understand the air-cooling challenge, look at the Jabiru engines that have engineered good airflow around the critical areas. A VW install could do the same thing for reasonable cost. Norm Heistand
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    VW Engines: Buy or Build?

    I have built a half VW piece by piece after purchasing a good used case that had been bored and stroke relieved. I would not recommend building the engine from a collection of parts. Instead buy a new or reconditioned longblock then add to it. My thinking is stock engine with small supercharger...
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    Supercharged engine

    Since the supercharger is simply an air pump, it would be easy to install a hose/tube from the blower output to the blower input. A variable shut off valve on the tube would allow changing the boost pressure "on the fly" with no other parts needed. Probably a way to have a control knob in the...
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    Supercharged engine

    I have an AMR300 small supercharger on my Predator 670cc V-Twin. See it running on YouTube: The same type of setup would work on any similar small engine as well. Half VW, 2A042, 4A032, Kohler CH27, Honda GX690, etc. For a 1600cc VW or 4A084 I would...
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    Freewing/Sprat Control Wing Development.

    I am currently building a Sprat103 from the plans set. The plans seem to be complete and adequate for me. My goal is low cost easy to build and fly legal ultralight. As far as maneuverable, what more do I need than turn and climb/descend? If you want maneuverable consider a plane like the...
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    The Sprat 103

    I suppose it is possible that there are more builders in France working on building a Sprat103 since it is a French design. I plan to finish my Sprat103 this summer and test it out. How hard can it be to get a powered kite to fly? And the design is based on the flying boat that is/was flying for...
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    The Sprat 103

    I can understand the critics of the Sprat103. There are very few of this design flying. My perspective is a little different. I have flown Cessna 150, 172, Rotec Rally, Benson gyrocopter, Phantom ultralight, and I have made emergency landings with the Phantom and the Benson. My engine failures...
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    The Sprat 103

    Re: Any Progress By Builders? I am currently building a Sprat103 from plans. I got the plans from Bernard in France. They appear to be complete and accurate to me. I am subsitituting a 5/8 inch axle tube made of 4130 steel to work with my Azusa wheels. All my steel materials are 4130 or similar...
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    Yes, I have a Half VW built and sitting in my shop. It has the 94mm cylinders and the 82mm...

    Yes, I have a Half VW built and sitting in my shop. It has the 94mm cylinders and the 82mm stroker crank. The intake is on top with a single Mikuni carb. The ignition is an electronic VW clone distributor with a sonwmobile coil. It is a full case version which I could bolt to a pair of aluminum...
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    1/2 vw and vibration...

    A counterweighted crank is mandatory for a half VW. After that you still need some dynamic balancing to get it smooth. I think there is a trade-off where a $150 Balance Master on the prop is less or similar cost to taking the crank assembly and having a dynamic balance done. I am building a 82mm...
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    Any thoughts on using an SU HS-2 carb on a 1/2 VW?

    Nothing wrong with an SU carb, however the Mikuni carbs are so common and easy to work with that I like to just buy a used Mikkuni on ebay. A 32mm is good for a half VW or similar. Some are running two of them. These carbs are on many snowmobiles in the US. Norm Heistand my .02
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    1/2 vw verses the 2ao42 2 cyl engine

    One easy analysis of the 2A042 versus other small engines is to look at the displacement. For example, a 730cc Kohler V-Twin is rated at 25hp. The 2A042 is 688cc. Just grade school math, 688 / 730 x 25hp = 23.5hp. This assumes equal carb and compression. The 2A042 carb is probably not adequate...
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    Engine sellers

    I am in the process of building my latest version half VW at this time. My goal is 40hp with a 82mm stroker with 94mm bore. Once I have my engine running really well, I would be interested in selling a half VW engine kit based on my engine design. Initially I will be advertising and selling just...
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    Half VW build costs?

    I am building a low cost half VW at this time. I am using a rebuilt case from WestCoastCore that is bored for 94mm and clearanced for an 82mm stroker. This case is only $515. I am using a new dual port head with 94mm bore from TexasAirCooled that will be cut in two to make two half heads. This...
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    which auto engine can run at full power for long periods?

    Regarding the discussion of VW engines: It seems to be true that the limiting factor for the VW heads is heat at the exhaust valve area. Note that the VW "air" cooled engine is really an oil cooled engine. A minor mod to the lifters and to the rocker arms provides more oil to the valve area and...
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    1/2 VW versus Briggs, Kohler, Generac V-Twins

    The 1/2 VW crank requires balance weights on the crank throws to make up for the missing weight of the other two cylinders. I believe a true 1/2 VW counterweighted crank from SCAT will run smooth. Hummel Engines sells the counter weights that can be welded on a stock crank. Norm H
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    1/2 VW versus Briggs, Kohler, Generac V-Twins

    The short answer to your question is lack of marketing and availability. A usual, everyone wants more thrust for less money. And they want an engine that is light and has a proven track record in the air. Homebuilders love to do it themselves (why they are homebuilders). The biggest problem...
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    1/2 type 4?

    The industrial V-Twins are attractive, especially since you get alternator, starter, electronic ignition at no extra charge. They are being used a fair amount on the powered paragliders. Of course an engine failure on one of those is a non-event. The 1/2VW (and 4cyl VW) have a good track...
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    Designing the Ideal Replica Warbird Engine

    Why reinvent the wheel? Talk to the folks that run boats with auto engines. Especially the V-12 from some Italian auto. There is no reason to spend a lot of extra money doing a ground up design. A V-12 would be perfect for the P-51 of course. Nothing wrong with a supercharged V-10 either. I...