This Engine is for a Boat i am designing. I got the idea for the engine from youtube and actually designed a 12 cylinder micro version first.
this engine uses size 130 DC motors with optical AB Phase Encoders mounted to the back of them (see: https://www.ebay.com/itm/130-Motor-DC6V-12V-7800RPM-Metal-Speed-Encoder-Tachometer-Motor-AB-Phase/192486576192?epid=18003843567&hash=item2cd1181040:g:hKUAAOSw5k1cdyBy )
gears and shafts are all 0.8 modulus plastic gears that come in assortments on ebay.
you need 8 motors, 8 82 pinions (8 teeth, 2mm hole) and 4 crown gears in order to make this work. the biggest crown gear it will accomodate is a 16mm outer diameter.
the heads are deigned to hold the motors and be cooled by either water, or an oil circulation, or worst case scenario air. in my case since i am going to install this one on a boat i plan to pump cool water across them as to dissipate the heat and hopefully be able to run these way over voltage. if i was to put them on a land vehicle i would use an oil cooling system that pumps past the jackets of the motors. and then recirculate into the gear system.
this design does not have a positive pressure lubrication system it uses a slosh or splash system to keep the gears lubricated.
to build the heads print 4 head plates and 2 head jackets. put silicone sealant around tthe edges of the lip on the plates. put all the plates together and let dry, insert the head to the block and apply silicone sealant to the entire dead surface. bolt on head with 10, 30mm pan head bolts per side. insert motors intot head and then asseble the crank and belly pan system .
the AB encoders are used to measure cylinder speed. i had issue with the previous version that when one motor would drag or go slower the gear would fly off of the motor shaft. so now using an arduino i can check the speed of each motor and adjust each motors speed to match .
another perk of this system is with a few added pieces of tech nology (boost converter) you can actually power half of the device and use the other half to charcge batterys or run other circutry. which is useful for long term deployment equipment . it also works alot better in the smaller N60 motor version than it does this big one .