Getting rid of a Grimmspeed AOS?

[Dean]

Why are you dumping it? I am very happy with mine.

IMHO opinion the people having issues with them are not routing the hoses right, just like the catch can people who fill them up.

[sedonabugeye]

Because they aren't very efficient with higher horsepower cars/higher boost.

[Dean]

Originally Posted by sedonabugeye

Because they aren't very efficient with higher horsepower cars/higher boost.

What does boost have to do with air/oil separation? Efficient? What do you mean by that? Are you saying oil is not getting separated? Do you have any first hand experience with them having an issue? What would you suggest in its place?

I've seen a couple guys on Nasioc who had an issue, but looking at their line routing, would say he had them routed under things, not over which is bad at minimum and quite possibly stupid given how liquids and vapors work. That is kind of like the guys with catch cans mounted lower than the breathers filling up cans and blaming it on the case vs. head breather line pressures.

[sperry]

Dean: http://forums.nasioc.com/forums/show....php?t=2228499

The GS AOS apparently has an issue with high HP and autox lateral gs. People are switching to the new Crawford AOS. I'm just not sure if the $400 for the Crawford unit is worth the extra money if you're not autoxing.

[sedonabugeye]

I had mine routed just fine. And didn't really have an issue with oil consumption, but more an issue over on the pcv side blowing oil out. Im also swapping to the Crawford because it seems to be more efficient for higher levels of boost. I also am changing up my entire setup and frankly just want something new. Entire new engine setup, so why the hell not? Its only money, right?

[Dean]

Originally Posted by sperry

Dean: http://forums.nasioc.com/forums/show....php?t=2228499

The GS AOS apparently has an issue with high HP and autox lateral gs. People are switching to the new Crawford AOS. I'm just not sure if the $400 for the Crawford unit is worth the extra money if you're not autoxing.

I looked through that thread before my earlier response, and both the original poster and post #24 have the center line routed down so any condensing vapor can pool and be blown into the intake as liquid.

Unless you have a really long and/or cooled path or VTA, it is pretty tough to avoid some vapor getting back to the intake, the goal is to avoid pooling, especially in the return hose.

The Crawford looks a lot like the Moroso stuff which is way cheaper. Wonder if it is just rebranded and price jacked?

I still don't understand what boost has to do with it unless you have a bunch of blow by which is not really the AOS's fault.

[sperry]

Lots of boost does mean more blowby, even on a healthy motor. I can see a 2bar motor easily overwhelming a small AOS.

The new Crawford AOS uses engine coolant to supposedly ensure proper temps for removing water vapor from the oil in colder climates. That alone might be worth the upgrade. Does the Moroso stuff do that too?

[Dean]

Did not realize the crawford did that. No, Moroso does not.

Heating is good. The crawford sounds a lot like the aviation ones I looked at back before the GrimmSpeed ones came out. But water temp is 160-180, not the 212+ you need to avoid condensation.

http://www.skygeek.com/airwolf-afc-w...rator-kit.html

I still think the people having trouble with the GrimmSpeed are largely due to hose routing. High HP might be a contributor though. It is relatively small, so only has so much surface area.

[k-dogg39]

Originally Posted by sperry

Dean: http://forums.nasioc.com/forums/show....php?t=2228499

The GS AOS apparently has an issue with high HP and autox lateral gs. People are switching to the new Crawford AOS. I'm just not sure if the $400 for the Crawford unit is worth the extra money if you're not autoxing.

I was having oil consumption issues that seemed to be very similar to this thread after my swap. My hose routing was all on top, not under anything. I was also seeing clouds come out of my exhaust at WOT. In addition I had a couple of instances during auto-x where oil had spurted out of the top of the Grimmspeed AOS on the filler tube. It was a bit odd.

I have since switched to the Crawford unit, I have only had it on for a couple of weeks, but it seems like so far my oil consumption has subsided, and I am not seeing the clouds at WOT either.

[sedonabugeye]

I keep my water temp right between 195-200. And I do run between 28-32 psi on my car. So the Crawford aos is going to be my next logical step in this. And using the coolant will aid in vaporizing the water vs having is sludge up in the filler neck.

[WRX06TR]

Originally Posted by k-dogg39

I was having oil consumption issues that seemed to be very similar to this thread after my swap. My hose routing was all on top, not under anything. I was also seeing clouds come out of my exhaust at WOT. In addition I had a couple of instances during auto-x where oil had spurted out of the top of the Grimmspeed AOS on the filler tube. It was a bit odd.

I have since switched to the Crawford unit, I have only had it on for a couple of weeks, but it seems like so far my oil consumption has subsided, and I am not seeing the clouds at WOT either.

Hmmm...sounds like what my car is still doing with the GS. Guess I may have to suck it up and pick up a Crawford at some point.

[Dean]

Sorry, I have turned this into a tech discussion...

The oil out the filler sounds weird, like a seal was missing or worse.

Guess I should pick up some clear hose an put it in-line.

Andy, that sounds high. Most people specifically try and lower water temps to 160-180...

Oil in the filler neck is still the most baffling part of all this. I guess a high quick initiation of a high G side load and then sustained could cover the bottom of the filler and then crankcase pressure push it up. I wonder if it is specific to a particular series of blocks? aren't the oil passages different EJ207 vs. 257, etc...

Doing more research, condensation is only really an issue for aircraft where temperatures are damn cold at altitude. There is no real reason for the Crawford design in automotive applications. Water is not going to condense at anything close to operating temp of the motor. Dew Point. Cold metal at start up or well after shutdown is the only thing that would likely have water condense. If you have the "white crud" there is most likely a bigger problem than just normal condensation as that should "boil off" as soon as the car reaches operating temp.

[sperry]

Well, people bitched about white gunk in the Crawford AOS before they added the coolant line (mostly folks that live in cold climates), and apparently the new AOS fixes the problem. So I'm guessing that it makes a real difference.

I think the oil passages are pretty similar on all EJ blocks. It's just the heads on the EJ2x7 blocks that get the extra set of breathers to help with high-G oil issues. But if Grimmspeed is specifically admitting an issue when autocrossing and is working on a new revision to their AOS, I'd say that's a pretty good indication there's more than just a hose routing issue.

[sedonabugeye]

It depends on if I run one or two fans.. Stays constant at 90*C for the most part.
I can get it a little cooler when I switch on both fans.

[k-dogg39]

Originally Posted by Dean

The oil out the filler sounds weird, like a seal was missing or worse.

Oil in the filler neck is still the most baffling part of all this. I guess a high quick initiation of a high G side load and then sustained could cover the bottom of the filler and then crankcase pressure push it up. I wonder if it is specific to a particular series of blocks? aren't the oil passages different EJ207 vs. 257, etc...

It was really odd. It only happend two times out at the courses in Fernley last year. I saw a couple of instances of this on Nasioc, but from what I remember Grimmspeed said they had one of their first batches come out with the wrong sized o-ring on the cap or something like that. I figured that was my issue, and I was going to hit them up for a new o-ring, but it never happened again.

[knucklesplitter]

Originally Posted by Dean

Did not realize the crawford did that. No, Moroso does not.

Heating is good. The crawford sounds a lot like the aviation ones I looked at back before the GrimmSpeed ones came out. But water temp is 160-180, not the 212+ you need to avoid condensation.

http://www.skygeek.com/airwolf-afc-w...rator-kit.html

I still think the people having trouble with the GrimmSpeed are largely due to hose routing. High HP might be a contributor though. It is relatively small, so only has so much surface area.

The Crawford has a clever baffle system that uses no problematic filter-like media and is better than the Moroso one or the one you linked to. It also uses the coolant coming from the turbo which is hotter than the average coolant temperature.

[szucchet]

ive had mine for almost 2 years with lots of auto x and track days and i have to say i love it. my car with 112k does not burn any oil (only burns coolant lol) it used to burn at leats a quart every 3k before. the only thing but its not really related is that the hose where it connects to pcv valve was brittle and it might of cracked a little bit when i was replacing valve cover gaskets so now it smells like oil after I park it in the garage after long drives

[sedonabugeye]

Some people have great success w it and others not so much. We're not saying its not a good product. Just wanting to go a different route w things on our higher hp and boost cars.

[renosubby]

The unit works great BUT it depends on how it is set up. If you have the Line that needs vacumm going to your intake you will have a problem with the turbo sucking out the oil if you have a bigger turbo. 55 lb/min or greater.
Austin (Gus Gus) has just recently witnessed this. I have an oil scavenge set up into my down pipe to prevent this.

So I believe the routing of some things may need changed for higher HP cars but overall a great piece of equipment.

[GusGus91]

Originally Posted by k-dogg39

I was having oil consumption issues that seemed to be very similar to this thread after my swap. My hose routing was all on top, not under anything. I was also seeing clouds come out of my exhaust at WOT. In addition I had a couple of instances during auto-x where oil had spurted out of the top of the Grimmspeed AOS on the filler tube. It was a bit odd.

I have since switched to the Crawford unit, I have only had it on for a couple of weeks, but it seems like so far my oil consumption has subsided, and I am not seeing the clouds at WOT either.

This is exactly what mine is doing too. Looks like a god damn diesel truck in WOT. I just ordered the Crawford. Well see how it goes.

[Dean]

I wonder if the real trick would be to run the "intake" line from the AOS to a catch can high on the firewall that is vent to atmosphere (VTA) instead of the intake. that way there is no vacuum drawing anything anywhere. Only crankcase pressure would push whatever through the AOS and then to the catch can.

[Kevin M]

Might as well delete the whole thing if you do that. The vacuum through the crankcase is the whole point.