Nearly 14 inches in diameter, and using some 12 square feet of plywood, this 7 cylinder radial is inspired by the engines that powered the Spirit of St. Luis across the Atlantic and helped America win WWII.  Features internal and external gears, a fully functioning cam plate, and authentic valve action.  Also features an authentic master and slave rod system.  See the Kickstarter for more videos and details.  (Note - detailed pictures load slowly, thanks to cheap web software.)

Price - $150 per kit

Animated Assembly Video

Changes made since the animation was made and the prototype was cut and assembled:  1) The timing idler gear was moved 0.005 inches upward to allow for more consistent engagement considering laser kerf.  2) The pushrods were lengthened 1/32 inch to allow for decreased valve clearance - again compensating for laser kerf.  3) The numbers have been reversed in order to go in the same direction as the shaft spins.  4) The supports on the rear case have been made narrower in order to allow a better view of the working components.

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