nope its not thanks riwwp for the insight

 

heres a pic

 

if i do bypass the can will i need to run a hose from the intake to where the neck is where u put the oil? (look at pic drawn outline) Thanks in advance

 

I think you are mis-interpreting the point of the catch can.

During normal engine operation, the crankcase gets pressurized due to normal laws of physics and stuff. The vacuum line at the top of the oil filler neck is there to use the intake vacuum to help equalize pressure. This also results in the draw of oil mist/vapor from the crankcase into the intake. This oil mist coats the interior of the intake track, including the intake valving. This is a direct source of most of the SSV problems that people have. If the oil accumulation is significant enough, you can also get oil accumulating in various points and 'flowing' forward onto the air filter turning it a nasty mess, which then gets drawn back over the MAF in a cycle, fouling that.

It's cleaner over-all to have something in the line between the crankcase and the intake track to catch all this oily mess. Usually the can will just accumulate oil over time, and it will have to be emptied periodically. I do not know if there is a viable way of having a 'drain back' to the oil pan, but it's probably possible with check valves and the like. Otherwise you have just added another source to pull vapor from.

2006+ RX-8s have this vent line going straight into the LIM, beyond the intake valves and it helps considerably with the fouling. It's not perfect though, but it's far better.

 

It's not a waste, it prevents oil from going into the intake if you somehow overfill, I would say leave it there. However, if you insist on taking it out just send it to me!

 

K im trying to understand

wouldnt the can empty itself? i notice theres another line on the bottom of the can (not sure where its going)?

Also the previous owner decided to just put a filter at the catch can instead of having a line from the intake to the catch can... is that ok? whats the point of even having that? i think he did it for looks only instead of having another line to the intake

 

lvis thats how mine is set up. no return to the intake. ive never had any oil in the can tho but i like the peace of mind that oil wont end up in my intake

 

A filter will actually catch more vapor than the can itself will.

Only way to know where that line goes is to follow it!

 

thanks for the quick responses! im understanding alot more.
another question, whats the best way to empty out the catch can?
im thinking of getting one thats clear or semi visible to monitor it

 

unbolt it and pull the drain plug. its pretty straight foward

 

This^ is what I got on my Subaru works very well... Im gonna see if it fits on the rx8 too.. that would be cool..

fyi.. Two outer bungs are for oil in...and the one center is for vac out to intake.. So i guess the i could work for our application..

 

well for the past few days ive been looking at all of the diffrent catch can set ups. from what i ve seen i think i will go with one that goes back into the intake port acc. question is, whitch can should i go with? one with the breather filter on it or not? & it sounds like i need one with a screan and or baffles. ( 05 rx-8 a/t all stock, 4,000 ml. on new motor ). any thoughts on whitch one i should get would be of great help, thanks, larry... ps. ive seen the ones on ebay, i just dont know if thay are trust worthy,

 

The weapon R catch can is good.. simple and it is shaped for a location that looks good... I would use that.. its the one in the picture. ^

 

Hell...i've seen ppl use soda can.
Srsly, it's just a can/container that catches extra oil.
Fancy brand oil catch can seems over killed on the price to me.
ebay cans will do just fine.
Some ppl just like to spend money on trash can.

 

1 thing i did notice is thatb there apears to be some oil residue under the breather, mabye previous owner spilt some oil when he emptied it?

 

funny the things people misinterpret, being an owner since early 2005 my intake accordion has never shown any mist, drops, or anything at all oil related - dry as a desert bone

I even ran an extra qt of oil the first three years or so competing in the SCCA factory-stock class ...

 

Either
A) Not all RX-8s are identical in this regard
or
B) There is a difference in driving conditions between your RX-8 and others. Humidity? Long low RPM cruise? Temperature swings?

I have dealt with oil accumulation in the intake the entire 110k of ownership, even if I make sure the oil level stays below the 'full' line. I have also helped pull apart the intakes on 5 other RX-8s and only one of those was dry.

It's a valid problem, even if your RX-8 doesn't see it.

Just like I have never had a rough idle after resetting fuel trims, pulling the battery connection, etc... Never. But I acknowledge that most RX-8s do have rough idle after this, even to the point of some have trouble with stalling.

 

good point RIWWP my first rx8 had no issues with oil in the intake 06 but the one i have now 05 have had some oil in the intake.. It also has rough idle after resetting the ecu or battery work.. my first one never did..

 

thanks guys for info on oil iol can. i wasent tring to hijack a thread, just seemed to fit in there. i still need to find out if i need a filter on my tank or not? looks like 1/2 do, and half dont, its like an oil thread! thanks, larry...