Searching for 2-stroke plan recomendation

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Usually, two stroke piston rings are located by a pin in the groove in the piston that locates in a step filed into the ends of the ring. This stops the ring from rotating and is positioned so that the ring ends are kept clear of all port openings. Some engines have a series of holes for the port opening instead of one long slot, so the rings do not bulge out into the port.

There is a ton of literature out there on two stroke port design, which is how they got away from the old peaked pistons. There is quite an art to it to ensure the fresh charge does not go straight out the exhaust port.

There is a good primer on it here
http://edj.net/2stroke/BellPerformanceTuning/Bell Chapter 3.pdf

ISTR Maytag made a flat twin two stroke engine too. That would be a nice one to make. Would have two separate crankcase cavities, one for each cylinder, with a seal on the crankshaft in between.
 
Lohring--I do like the look of that Hallam--unfortunately, I can't read it. When I print it out it is just too fuzzy. Can't read it on the screen either.---Brian

Brian

I can read the original but it is still a poor drawing. I can email it to you if you want. As someone pointed out, the http://modelenginenews.org/ has a wealth of information as well as the Hallam plan.

Lohring Miller
[email protected]
 
When I was a kid, I had an old Evinrude 2 cycle boat engine. It ran slow, idled slow, and started easily. This is far more in line with what I want t build. I can't believe that there are no engine plans for model versions of that type of engine out there somewhere.---Brian.
 
I still have the plans from the engine I pictured, but I wouldn't build it today. As was posted above, I would build a Schnerle ported engine with a piston port intake. The world is full of examples of these engines in weedeaters and chain saws. They are very inexpensive. Homelite has one of the least expensive versions that costs less than $100. The overhung crankshaft design would be easy to make. I've been modifying this type of engine for years. I can give you porting details. You may be interested in a series of articles on two stroke design as well as one on modifications for model boat racing. I can send you copies if you want.

Lohring Miller
Blowup1.jpg
 
Don't remember where I saw it but there was a 5 cylinder Maytag rotary engine around a couple years ago. Had a stationary crankshaft and the cylinders and crankcase spun.
 

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