[88FieroGT]

I pretty much cant ask questions about my design without giving anything away. But as far as modeling/ construction techniques and how to's definitely can ask questions about that.

My biggest concern is engaging wear , big downward spiral on my design if it cant hold I see the motor being completely destroyed. But the advantage is with more mechanical advantage the motor revs at lower rpm for the same hp so that wear will be reduced exponentially......At the peak stresses , that is where there is the least contact area. I am unsure if I can overcome this with more robustness and keep timing from going completely out of whack and make it so it will not being able to be regulated and if that extra robustness will just exponentially create more stress to where the design cannot work or create too much inefficiency.
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If I make a model out of wood , I need a way to test it , assuming my best options is on the crankshaft with an electric motor for the input and measure the output , plot and graph a bunch of points and compare. This way would incorporate all the same friction as making the input force on the piston face vs on the crankshaft because everything is still moving , while having an easier and cheaper test method. Since the piston face would need an actuator with a timed event. While the electric motor can have a constant run since the crankshaft pretty much always rotates at the same rpm acting as a flywheel unlike the pistons with their full accel and decel , So as long as each model has as best possible tolerances to each other as possible to make them run as smooth as I can get them. Using a fully balanced engine design or as balanced as possible greatly helps here , especially with subpar testing , materials and manufacturing I imagine I should be able to do the test and make the models out of wood. I will do the test free flowing , as far as no heads to minimize pumping losses since the electric motor input mimics a constant air/fuel mixture and volume , Even though pumping losses will still exist , I suspect it will give me a more better reading on the engine efficiency.

How I think I should measure the outputs is , since electric motor efficiency changes from rpm to rpm , run each engine at the same rpm , and measure its amp draw. That way I can compare the amp difference from one motor to the other giving me an efficiency reading. Do this for various rpms , I could then measure the amp draw of the electric motor not being hooked to the engine. Then if there are any specs for the electric motor as far as what its efficiency ratings are at each rpm , do a little math , and calculate what the efficiency of each engine is at a given rpm.

My question is does anybody see any improvements in testing methods? On either making the testing easier , suggestions , and problems or overlooks I have? along with a discussion on them so I can know exactly why it is a problem and why to use a different method?