Are rotaries dry sump?
 

Are rotaries dry sump since they don't have a "vat" of oil that the EC runs through, instead it's pumped around the engine?

No. Unless you convert them to it.

Dry sump is totally different. In a dry sump the oil is sucked out of the engine and placed in a separate holding tank (usually de-aerated first) and then another external pump takes oil from that tank and pumps it through the oil passages. All the oil pan does is keep the oil from falling onto the ground :)

Rotaries as we know them are still technically wet-sump, since the oil system is all internal.

I do have dreams of converting a rotary to dry sump, though. Use the stock oil pump as a scavenge pump, the stock front cover line as the line out to a nice, tall, narrow tank...

Wouldn't that be the shit to have,,huh ?
the external oil pump is belt driven,,in most cases

Dry sump front cover is $2000 or $3000 depending if you want the american or japanese made one.
Then several hunderd $ for the pump, plate, hose and fittings. U only need it on a racetrack when you're taking serious g's in a corner and the oil pickup tube can become uncovered and the motor starved for oil.

Absolutely overkill on the street.

If you're worried about oil starvation with your street or track school driving, just pour another quart of oil in there.

-bp-

It would make it a lot easier to put a rack and pinion under the engine if the oil pan was flat...

Mazdaspeed had it in their old catalog. No price but the dry sump kit looks expensive (a few grand).

I think there is a way to make your own. i saw a hommade one for sale on the parts trader like a year ago. It would take some real fabbing thuogh, but better than shelling out a few grand.

CJG