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I believe, maybe, Ti is the time (T) the engine crank case is in vacuum inhaling (i) air.

I cannot believe how much oil these cars breath.

I installed a Grimmspeed AOS which works well for the head vents, the return line is clean and dry, BUT, the crankcase vent is still OEM and is oiling up the intake and IC.

Even with all the information from here Im still trying to work out my best option for doing the crank case.

Not really wanting a can which requires emptying or plumbing into somewhere to return, I may try adding the crank vent it to the Grimmspeed AOS, one for crank, one for heads, just hope the return pipe is sufficient.

Bloody cars, I had the same but different issues with my R33 (oil surge), fixed with big VTA can that returned oil to sump, no PCV valves to be seen

I'm sure it is easy but my brain is full from so many different methods.

Plus I'm not keen on spending to much money on something that could be fixed by running some hoses and venting it out under the car (bit messy though).
 

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Cake Eater;4292552I said:
... installed a Grimmspeed AOS which works well for the head vents, the return line is clean and dry, BUT, the crankcase vent is still OEM and is oiling up the intake and IC.

Even with all the information from here Im still trying to work out my best option for doing the crank case.

Not really wanting a can which requires emptying or plumbing into somewhere to return, I may try adding the crank vent it to the Grimmspeed AOS, one for crank, one for heads, just hope the return pipe is sufficient...
It seems like I recall that many feel the Grimspeed unit is a poor solution and inefficient. It's really not that difficult to let a catch-can return the oil to the crankcase. Easier if you ditch the PCV valve. I think that approach is pretty well covered in this thread. I bought a very inexpensive, tall catch can called an oil breather tank. I then mounted the breather remotely and covered it with a sock. Now, this is for a race car with blowby. Still, the sock takes days of track time before it starts to get wet.
 

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@Scargo I appreciate your detail respond but you may have misunderstood what I am really asking here.... After reading 1720 post, I certainly get what you wrote above ^^^^^

I am just curious about what bb999 said and whether it make sense to you and that's all.....let me put what bb999 said below one more time. Now, is off boost the best time to burn up blow-by via the intake manifold and it really doesn't matter whether you have a CAN between the PCV and the IM ?

The idea of 3 cans is essentially wrong, blowby exits the motor a from only 2 places: the crankcase and the heads. intercepting UNDER the PCV Valve and where the head breathers "T" together is all you can/need to do. with this method any system can be made to work with or without a PCV Valve. Intercepting above the PCV Valve causes the intended mixing function of the "pinhole shminhole" to be altered. Off boost is the best time to burn blowby, this is why the group N routing for PCV is VTA but also keeps the IM connection, routing the head breathers to the TI port of the PCV valve. you however do not want your intake manifold, valves and pistons coated in oil so keeping it out under all circumstances is best. with that said VTA is suboptimal especially for a daily driven vehicle, it is a track setup.
 

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It seems like I recall that many feel the Grimspeed unit is a poor solution and inefficient. It's really not that difficult to let a catch-can return the oil to the crankcase. Easier if you ditch the PCV valve. I think that approach is pretty well covered in this thread. I bought a very inexpensive, tall catch can called an oil breather tank. I then mounted the breather remotely and covered it with a sock. Now, this is for a race car with blowby. Still, the sock takes days of track time before it starts to get wet.
Ive hooked up the crankcase to the Grimmspeed AOS, the return hose from the heads was clean and dry prior to this, so far after about 500 km the return is still clean and dry.

I just cleaned out the TMIC with brake clean, I will inspect it again in a couple weeks and see if it has worked, or if I need to supplement the AOS with a catch can.
 

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you should really clean your tmic with GAS not brake clean, its impossible to get it all out and things like diaphragms, gaskets and injectors are not happy with brake clean.
 

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Clean as a whistle on the OUT side,
I forgot to take a photo of the IN side of the intercooler but that was clean and dry too.
Pretty happy with my Mishimoto 3 port catch can.
5 track days and about 20,000kms travelled

Running Cobb Stage 3 + FF



Sent from my iPhone using Tapatalk
 

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I promised pictures of the Radium Engineering unit installed on my 08 GR STi and forgot. This weekend I will clean up under the hood and get some. Fantastic work of art it is for sure.
 

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So you're using the air intake as your venturi vacuum to clear the heads and crankcase of blow by, which is fine if the oil is actually caught and doesn't make it into your air intake tract. Keep an eye on it.
 

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I have an IAG street series AOS installed that is seeping oil from the bottom edge around the can itself. I've had a shop check it but it started to again, IAG states it maybe positioned a bit too low in the engine bay. It sits about an inch from the top of the engine bay in a 2016 STi (if that matters). Anyone knows what may be the culprit?
 

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I am going to dumb this down. I put a new short block blueprinted, forged pistons and crank of course. course in my 13 STI, Stage II protune access port normal stuff. Ran great during session but when I would restart the car, All this blue smoke would come out the exhaust and then stop. Still ran fine and afterwards when I took it to my mechanic he said go back to conventional for a 1000 miles then but the Crawford and go back to synthetic. this helps seal the rings.
Been back to the track about 5 time and the problem is 100% fixed. At least that's my story. Going next week but I am sure the smoking issue is fixed. We install the lik just as the manual said and it is sucking from both heads and intake
 

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I have an IAG street series AOS installed that is seeping oil from the bottom edge around the can itself. I've had a shop check it but it started to again, IAG states it maybe positioned a bit too low in the engine bay. It sits about an inch from the top of the engine bay in a 2016 STi (if that matters). Anyone knows what may be the culprit?
because the o-ring for the bottom was designed in a way that is inappropriate for vacuum applications.

it boggles my mind that there still is not one product out there that ticks all of the boxes laid out in this obnoxiously long thread. i need to buy a welder.
 

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because the o-ring for the bottom was designed in a way that is inappropriate for vacuum applications.
Is the o-ring sitting in a counterbore only? No o-ring groove? That could certainly explain it, but I'd be surprised if the low vacuum would be enough to dislodge the ring. Possible I suppose.

because the o-ring for the bottom was designed in a way that is inappropriate for vacuum applications.

it boggles my mind that there still is not one product out there that ticks all of the boxes laid out in this obnoxiously long thread.
Weed, the problem is no one has the same checkboxes... Do you want it to look cool? Function? Be easy to install? Inexpensive? VTA? Catch or drain? Maintenance free? Heated?... The list goes on.

Here is ours if you haven't seen it. It checks the function & performance boxes first and foremost, as I have always been a function first kind of guy, and was not satisfied (and had been coerced by the market) with the capabilities of the market offerings. Does this hit everyone's checkboxes? Highly doubtful, but it definitely performs to it's purpose.

 

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... it boggles my mind that there still is not one product out there that ticks all of the boxes laid out in this obnoxiously long thread. ...
I agree with Chris. Looks like KB's is a very good design but doesn't deal with "mayonnaise" worriers with DD's.
Perhaps my Crawford would be OK in a DD situation but with my 24 PSI race motor it is letting some oil get by (which goes into a catch can/breather).
Nothing's perfect/no one size fits all.
 

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Is the o-ring sitting in a counterbore only? No o-ring groove? That could certainly explain it, but I'd be surprised if the low vacuum would be enough to dislodge the ring. Possible I suppose.
the o ring should be compressed between mating surfaces like a flange instead of relying on the static tension created by sliding it up in there, not to mention how easy it would be to nick the o ring on the way in and the tendency of o rings to roll as they are installed. using a ring with a square cross section might help but it is just not a good design.


Weed, the problem is no one has the same checkboxes... Do you want it to look cool? Function? Be easy to install? Inexpensive? VTA? Catch or drain? Maintenance free? Heated?... The list goes on.

Here is ours if you haven't seen it. It checks the function & performance boxes first and foremost, as I have always been a function first kind of guy, and was not satisfied (and had been coerced by the market) with the capabilities of the market offerings. Does this hit everyone's checkboxes? Highly doubtful, but it definitely performs to it's purpose.

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yes i have seen yours, you guys made a great track day product.. I am well aware no product ticks all the boxes, even my current setup is not what i would like it to be.

heres the way i look at it, all of the best mods take what we were given by the factory and use better materials and more costly production techniques to give us what the factory deemed not cost competitive. most aos systems try to reinvent the wheel instead of just making it more round.

2 cans of large capacity with tangential inlets
swirl inducer ring
valved drains to act as aos OR catchcan
spill free fittings for the coolant so it can be heated or not.
serviceable

its not exactly a long list

I agree with Chris. Looks like KB's is a very good design but doesn't deal with "mayonnaise" worriers with DD's.
Perhaps my Crawford would be OK in a DD situation but with my 24 PSI race motor it is letting some oil get by (which goes into a catch can/breather).
Nothing's perfect/no one size fits all.
yes it is a good design, but you seem to agree with me that it will not serve daily drivers of cold climates. the crawford will always let the gunk out because the design dosent let the can drain until you shut the car off
 

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Got the Perrin AO kit for my 18 Sti. Does anyone know if dealer voids warranty cus of it? Prb should have asked them before spending cash lol
 

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2 cans of large capacity with tangential inlets
swirl inducer ring
valved drains to act as aos OR catchcan
spill free fittings for the coolant so it can be heated or not.
serviceable

its not exactly a long list


The moroso setup is really close to your list, just without the ability to be heated. I find that waiting 10 minutes or so after shutting the car down allows enough heat from the turbo to sufficiently heat the cans and allow all gunk to run out.
 
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