anyone has experience with rotary engines?

**speedyfix** · May 9th, 2006 11:26 PM

iqaruzz, the reasons you stated for the percieved increase of displacement of the rotary engine is wrong. it's not because the engine has 2 rotors (which it does), but rather because it normally requires 2 rotations of the rotor for it to be considered as one combustion stroke.

so normally it's about 600+cc per rotor x 2 rotors x 2 rotations
or in the cosmo 3 rotor engine it is 3 rotors x 2 rotations.

you come up with close to the approx equivalent piston engined displacement but use the wrong formula.

**iqaruzz** · May 17th, 2006 09:14 AM

Originally Posted by speedyfix

iqaruzz, the reasons you stated for the percieved increase of displacement of the rotary engine is wrong. it's not because the engine has 2 rotors (which it does), but rather because it normally requires 2 rotations of the rotor for it to be considered as one combustion stroke.

so normally it's about 600+cc per rotor x 2 rotors x 2 rotations
or in the cosmo 3 rotor engine it is 3 rotors x 2 rotations.

you come up with close to the approx equivalent piston engined displacement but use the wrong formula.

Yes, you are quite right. Just simplifiying in to lamers term.
Formula I've given actually lacks of details. ("brief summary to cc ratings")
What I understand about this is, each face of the rotor is 650 cc and there are three face, two rotor. It takes 3 eccentric shaft rotation cycle to complete one engine cycle. Weird in a way its like a 3 stroke engine.
So in one engine cycle it actually did 3.9 Litres.

Hmmm, if you have a total of 2 rotations of the eccentric shaft in comparison to 2 rotations of the crankshaft in 4-stroker. The 13B would be actually 2.6 litres.
Reason I did this way is I have previously explained it to few people who hasnt worked/seen rotary engine. And actually took me few hours trying to explain it. My bad!

**speedyfix** · May 17th, 2006 10:55 AM

don't worry about it

you should always bring a diagram of the engine para maexplain mo sa di pa nakakakita. hehe!

**mini888** · March 14th, 2007 05:27 PM

Originally Posted by orly_andico

the rx-8 renesis engine requires a full synthetic oil change every 1000-2000 miles!!!

that's because the apex seals are made of some soft metal. if you don't do the recommended oil change interval, they will wear out very fast.

that's what makes the routine maintenance so expensive, imagine full-synthetic oil change every 3000km.

You are totally off here. For RX-8 Renesis engine, it is recommended that you use mineral based engine oil, not fully synthetic. I am currently using Quakerstate 5W-30 (found it at True Value). As for the interval, I am planning to change it every 5,000 kms. As for any mechanics in the Philippines, I am still looking for one.

Regards.