several things I have been thinking of,

-temps of oil in the event of blow by, is your reservoir capable of that heat?

-bad gasses and vapors in your reservoir

-Venting your reservoir?

-Vacuum on your reservoir. you dont want vacuum on it thats for sure, the sohn is only gravity fed it wants no vacuum to feed properly so you will have to vent it out.



... might as well just suck it up man and get a catch can jeez

 

My reservoir is very thick and meant for holding coolant so temp wise I don't think it's an issue since any oil that went in would just mix with cold Idemitsu. The SOHN reservoir I use is already vented in the cap. I would also tap the top and install a nipple with a breather filter just to make sure it is vented enough. The Ebay seller I bought it from will install inlets and outlets on the reservoir wherever you want, you just have to let him know when purchasing so I may just order another one. Having on less reservoir is a good thing.

 

why are you venting to a can with a breather filter just slap the breather filter on the oil feed and call it a day.

 

Because just slapping a filter on the oil filler pipe can be messy if it does puke up oil and the filter can get clogged and then you will excessive crankcase pressure.

 

True true...

sohn it is!

 

I have an extra SOHN reservoir, I guess I'll have to experiment

 

you can use the sohn I guess.
one hint though---if you know you are going to be doing some spirited driving like track days or something--lower the oil level in the oil pan by maybe 1 mm on the dipstick. We have found after tens of thousand track miles from the Ga rx8 club members, that in doing this it really helps prevent puking of oil. It doesnt matter what type catch can you have, this helps. Lowering the level by that small amount doesnt affect anything.

 

Yeah I have learned to not fill it up all the way, I usually go 3/4 of the way to the top mark.

 

Guess I must not push hard enough then since I have run way over the full marking in the past and never puked oil

 

It's because your granny shifting and not double clutching like you should be. Noob

 

lol--that was my first thought too!
But it seems that we have had more problems with puking ( various amounts) on tracks that require high rpm, high load, high speed, high g forces for a lenght of time. Quicker accelerations in the lower gears and stopping like on shorter tracks doesnt seem to cause this problem for us. IDK? The guys that autocross here, have never seen it either.

 

PIR (RIP), FIR-east, FIR-west, FIR-main, FIR-Mondo, CalMoSp, Big Willow, SO-Willow, Buttonwillow, AMP, INDE, Arroyo Seco, Laguna Seca. And that is just the West Coast.
I've run ALL of those regularly - some with high-speed, NASCAR-style banking; others with short, hard braking and turning - and I NEVER "puke" oil.
Neither do the 1/2 dozen other RX-8s I run with regularly.

If you are "puking" oil, you are pressurizing your crankcase.
If you are pressurizing your crankcase, you are doing it wrong.

 

It's a weird issue, I personally only had the issue once years ago and I was stock and when it appended after the turbo install that was purely my shitty catch can. When I picked up Hoss-05's car (bone stock at the time) when he left for Afghanistan I found this:

http://www.flickr.com/photos/9krpmrx8/4449778038/
http://www.flickr.com/photos/9krpmrx8/4449777584/

 

Maybe consider asking yourself how oil from the sump entering at the TB manages to blow back onto the intake box filter?

 

I have no clue how that happens.

 

I havent had any puking in a long time.
I did have puking with my last engine blew but I dont count that.
Only one way oil can get to the TB etc and that is blow by from the "crankcase" upward. This is excluding having a vacuum line from the oil filler pipe to the intake--that is an obvious one.
The oem oil filler pipe IMHO is poorly designed to bleed any pressure off--it has to many turns and air doesnt like taking turns. if you REALLY want to vent the oil pan area--hook a line up to the dipstick tube and run a breather type catch can to it. It would be a pita to deal with, but it is a straight shot to relieve any pressure and I have seen it work.
I have seen two types of blowby or puking. One is a small amount over time, the other is a large volumne over a short period of time. To deal with the later you have to have a large hose leading to the catch can as the oil is just too thick and there is too large of a volumne for a small line to handle. Obviously both can because by the same thing OR the large puke can be caused by an acute event.

 

Ill blame it on my Ex Wife driving the car while I have been away and before Scott picked it up.

 

Not sure what she could have done to have caused it but maybe the missing vacuum cap on the LIM had something to do with it?

 

maybe she drove through an oil shower and took it in through the front of the airbox

 

Hard driving and downshifting on 04's creates back pressure when downshifting especially when downshifting before a turn. You have vacuum created while accelerating before the turn then the tb closes creating negative pressure any oil that was coming up from the breather tube is now pushed back towards the ends of the accordion.

keep in mind we don't have a pcv valve or a check valve on that line its a straight shot to the accordion.

 

you may want to keep in mind that a pvc or check valve would only inhibit something from getting to the sump from the intake, not the other way around

 

Hmmm In all of my other cars (91 300zx, 96 celica) a failed PCV valve meant oil in my intake manifold and oil fitlers. But whatever works...

 

The phrase 'much ado about nothing' comes to mind for some reason .

 

was it connected directly to the manifold and then also experiencing intake pulses directly or was it connected before the TB like on the RX-8? It's only real purpose is to vent hydrocarbon crankcase gases back into the engine rather than venting them directly to the atmosphere. It's simply an emissions strategy.

Think about what it takes to push oil vertically from the sump up a small tube to the intake point, it would require a lot of blowby to accomplish this

 

I think pouring fresh engine oil in the spout too quickly and having it burp back up into the crossover tube and down into the accordion is a pretty strong possibility in some cases too.



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