sonofthehill

iTrader: (1)

I was so happy with the catch can(working well a couple cc every couple hundred miles.) I decided to do another one on the exhaust side venting to the air filter.
I mainly wanted to try and get rid of an unburnt fuel smell I get sometimes at full boost. I have everything else sealed well, no exhaust leaks. The only thing I can think of is the filter on the exhaust side crankcase vent.
So far so good, it's a bit cold and I need my windows open to tell. I did have a good open window pull today and I didn't notice anything.
Seriously need to spend a little time making a bracket or 2 for these.



Gold one from harbor freight, black one from home depot. Very slight differences.







I am starting to hate this bracket(old horn bracket)

deezums

iTrader: (3)

I have friends that comment on that all the time, maybe I should make another...

I replaced all the fuel stuff too, so I know it's not leaking. Just fuel stink after a boost run.

Just plumbed into the filter, no fancy venturi?

sonofthehill

iTrader: (1)

Just a 1/4npt fitting force threaded into a 7/16 hole in the thick rubbery plastic top of my crappy air filter. After one of your catch cans of course. The home depot one was twice as much but slightly different we'll see how it holds up.

NBoost

Interesting. Could the same end goal be achieved by running a one seperator set up, but plumbing both lines from the valve cover into one seperator, using the IM source for Vac? Obviously in a configuration that would keep you from "boosting" your crankcase.

Seperators work pretty well, but the one hooked to your air filter will still put oily residue all over the inside of the whole IC piping system, eventually. At least the IM source will burn any remaining oil vapors

sonofthehill

iTrader: (1)

Unfortunately it won't work because I am trying to get rid of crankcase fumes while in full boost. The IM is full of pressure at that time so it won't suck the blow by in. The only other idea I had was to run the exhaust side breather through a long *** hose to a mini filter near the tailpipe. But I like that idea less. Maybe if you got clever with a port in the end of the tailpipe and a spark plug it could be cool. Could be dangerous too, try at your own risk.
I think pcv fumes in my lungs will cause problems eventually too, so I would rather clean my IC and charge piping at that time.
Very little oil collects in that side compared to the intake side. I think most of the time it is a source of clean air. Just not when my bomb *** modified pcv valve sees boost and seals up, then pcv vents out the exhaust side and I smell it.

aidandj

iTrader: (5)

If there are oil vapors it will lower the octane rating and can lead to detonation. Thats the whole point of the air/oil seperator. The point of having one plumbed to the intake and one free/intake piping is to get clean air flow through it and to get rid of nasty stuff. Hooking them both to the IM would not do this.

NBoost

I see. If oil vapors are such a big concern with lower octane rating, putting the engine at risk, why not use another source to pull negative pressure on the crankcase? Infact, the intake manifold doesn't seem ideal at all being that a boosted car's intake manifold see's more positive pressure than negative.

By another source, I was thinking a hose in the post-turbine exhaust stream. It always seems tough to get it to work properly (based on the threads I have read about it), but I wonder if possible once its revised a bit.

aidandj

iTrader: (5)

Thats what the catch can is for....

I have one of the exhaust venturi things. Forgot to weld it in last time I had the downpipe out. I've heard good and shitty things about them.

deezums

iTrader: (3)

You say you've read the threads, but I don't think you have.

PCV valve only works on high vacuum, the same stuff that pops your blowoff valve. Any time you've got low vac, the block is pulled clean. Happens a lot, more often than boost on a street car.

NBoost

Right, but removing the intake manifold from the system completely, would result in no need for a separator.

Do implement the venturi, It would be nice to see it if it does/doesn't work on the typical turbo BP set up.

NBoost

True on the high vacuum part, didn't initially think about that. But it would be nice to have a system that increased crankcase venting, as boost increased. Which I think is possible, but seemingly not by using the intake manifold as a vac. source.

deezums

iTrader: (3)

It vents fine, unless you run the other vent to the intake manifold.

It's also nice not having a car burn oil in boost, or at least look like it is.

sonofthehill

iTrader: (1)

If you think that is a good idea, you should implement it on your own car. If it works well the rest of us might give it a try.
The only real source of vacuum in boost is the air filter/box.
Some fumes still seem to escape but it seems better than with just a mini filter. Maybe if I run a v8 OEM air box with a cold air duct I could keep the fumes contained. Maybe there is something I overlooked but there doesn't seem to be.

sonofthehill

iTrader: (1)

Here is about 400 miles worth of caught oil. The exhaust side doesn't seem to be putting much oil out and I still smell some fumes.

sonofthehill

iTrader: (1)

Picked up a nice stock bore block today from a friendly fellow miata guy. Couldn't pick a better spot to buy a couple parts.

Dirtmafia

Glad I found this thread, I will be following

It was good meeting you yesterday, Cheers.

sonofthehill

iTrader: (1)

Good to meet you too! The block is in good condition, perfect for my almost new crank. Thanks!

sonofthehill

iTrader: (1)

Easy, a hair over 3.5 hours complete swap.

nigelt

iTrader: (10)

Swap of what?

Girz0r

iTrader: (1)

Trubo to Stock BC Calinazifornia.