2 Crankshafts Inverted v8

[BentRods]

Kind of interesting with what you guys came up with, looks like I got the gears turning for some of you. Below is a sketch I drew shortly after the first one and it looks like some of you were going down a similar path. The top sketch shows the head with a pitched roof with two cams vertically in line geared together that would somehow activate the valves on both banks simultaneously, possibly a wedge type mechanism?

The lower sketch shows pistons with heavy chamfers that would protrude out of the block to increase compression ratio.

Again, some of you may ask why, and I can't justify it either, other than a new challenge. The funny thing is, I'm actually a full time CAD designer but I tend to sketch out all my ideas first.

 

[johnny1320]

It's interesting, but I think making it a two stroke would be more efficient intake on the left bank exhaust on the right, might need a high dome piston to get enough compression.

 

[Henry]

Really interesting. Keep the pistons as simple as possible. Like you all know one of the problems is to accelerate the piston in one direction, to stop it and then accelerate it in the opposite direction, that imply a huge lost of energy, any effort to minimize the mass of the pistons yields more energy.

 

[dman]

Really interesting. Keep the pistons as simple as possible. Like you all know one of the problems is to accelerate the piston in one direction, to stop it and then accelerate it in the opposite direction, that imply a huge lost of energy, any effort to minimize the mass of the pistons yields more energy.

that's a big mis understanding of how it works. there is a lot of force in piston acceleration but the force goes in both directions on the crank shaft. when the piston nears tdc it slows down stretching the rod and pulling on the crank pin trying to speed up the crank. as it reaches tdc and the piston direction reverses it trys to stop the crank like people believe but being it accelerates at the same rate for the same time it took to stop the crank energy that you lose only exceeds the energy it previously gained by the amount waisted to heat via friction and sound energy or fatiguing in the material.

heavy pistons don't make energy disapear. that's a total myth. but at full scale it does make life hard on con rod bolts.

 

[John Rus]

A bit off topic but cool http://www.ukpapermodels.com/phpBB3/viewtopic.php?f=4&t=450&st=0&sk=t&sd=a&start=105

I really like this link because I have been mildly into paper modeling for about 10+ years, pretty amazing what you can do with paper.

Cheers,
John.