So I'm probably asking a stupid question but I cant get it out of my head for some reason so I had to ask. Obviously the rotary is taller than it is wide, so why is it standing up? If you mounted the motor port side down (or spark side down) youd have a (somewhat) lower CG. Now, from what I can reason, this would take a few tweaks to make work such as a dry sump system, and rotating the PS pump (if you keep it) 90 degrees. But am I overlooking something major here? To me it seems like it would work, and especially well for a dry sump NA setup. I'd like to hear your thoughts, (or just tell me I'm stupid and why )
-Heath

 

That's a **** ton of work to move 20 pounds (if that) 4" lower.

 

yeh agreed. would be too much work for not enough gain

 

right but why didnt mazda do this in the first place is what im wondering?

if youre motor is out, its dry sumped, and youre building runners for NA then why not build new motor mounts while youre at it

 

yes ,, the middle plate is used as a path to allow oil from the rotors to gravity back to the sump
- the passage for this is down the spark plug side

putting it port side down will force the oil to accumulate in the rotor
- as it has to travel against gravity as this passage is now UPPERMOST

let alone the oil leaks from the now vertical sump line

if at all ,, the method may work if the port side is UP, spark side down
because at least gravity will assist oil returning from rotors to the middle plate passage

ideally ,, a 45 angle with sparks down would be best
as all directions of the drain channel will be DOWN with gravity

 

Aircraft guys do it all the time - search for "plugs up".

Now, if you wanted to move the CG lower, you'd have to mount the engine plugs down, because the widest part of the engine is actually the port side. Manifolds take up room, too.

That is assuming that there are no accessories.

Accessories on one side, manifolds on the other, the best way of mounting it is oil pan down. Odd, that.

 

It's just not realistic for automotive use. Dry sump or not, as stated before the oil uses gravity in its return system. As does the coolant system, not to mention the issue of the transmission in an automobile.

And these things would become an even bigger issue if said engine was turbocharged.

-J

 

The reason the aircraft guys run plugs-up is so the oil still drains panward.

The oil return path in the engine runs diagonally, from top left to bottom right. If you run plugs up, the oil still will flow down to the oil pan area. You just need to make a modified oil pan and oil pickup tube. Dry sump is not required at all.

 

Actually in small aircraft, the location of the intake and exhaust are just easier to fit in the small space they have when it is oriented that way. It's none more complicated than that. The exhaust just goes out the bottom and with the intake wrapping around the top of the engine, it actually becomes the side in an airplane and that is where the inlet comes in. The opposite side of the engine which was the bottom before is now free to add accessories. They only have to fab up a new oil pan and pickup system but they typically don't even go dry sump. There's no reason to do it in a car.