Killer B Motorsport 2022+ FA24 BRZ/GR86 Oil Retention Baffle Development

[OkieSnuffBox]

Originally Posted by gnarjunkie

100%

Driving even super hard on the street doesn't put anywhere CLOSE to the stress on a car that track driving does.

Even in the case where someone has a fast curvy road, that they know extremely well, that is 100% clear of any traffic, on 200tw tires, where they are willing to push every corner up to the point of potentially going off the road... there's still the fact that you probably can't do lap after lap after lap of that section for 20 minutes straight without interruption.

And to go along with that, anyone who has been to the track multiple times is typically not pushing like that on a public road.

And someone who has never been to the track and been with an instructor, or had an instructor drive their own car, aren't pushing the car nearly as hard as they think they are.

[900BRZ]

I did one autocross event post-pressure instrumentation, so I can take a deeper look at that data. It was difficult to parse because I forgot to set up the Aim in a point-to-point mode vs circuit, so I ended up with a lot of laps put together and there are expected pressure drops as I’m waiting for the next run.

[900BRZ]

Originally Posted by Frost

Also, I'd like to add, the video does make mention of first gens not getting as severe and as long pressure drops on the same turns. Any chance we can get full lap of the first gen followed by a full lap of the second on the same track?

Thanks!

Yes, that’s a good idea.

[900BRZ]

Originally Posted by Frost

As someone who has spent 13+ years in the pump industry (specifically chilled water loops, heating and fire pumps), I would caution the implication that cavitation is the cause of the pressure drop. Given the way the oil system has to wait for oil to drain back to the pan, the oil pickup isn't pressurized. Correct me if I'm wrong, but in this case the oil pump actually has to suck oil UP from the pan to pump it through the engine.

EDIT: Please note, I am writing this to add constructive feedback to the the diagnosis, I LOVE your critical breakdown and data. I mean no disrespect. You have provided by FAR the most data driven analysis of this problem. Many thanks.

From having seen internal documents within Subaru, they said they adjusted the shape of the pan to reduce frothing at the pickup. I assume this is more to ensure that consistent oil flow can be had at the pickup. This leads me to my point:

I think the issue is that the pickup is not reliably being presented with oil to suck up. The pump will cavitate as a result but the cause isn't the cavitation but a byproduct. If frothing was an issue, the easiest way to have fixed that was either to make the pickup go deeper into the pan where the highest amount of G doesn't affect it BUT you also have to consider the oil return coming back is actually hitting the spot where the pickup is intaking oil. If the G is high enough, maybe oil isn't flowing back to that spot. Short of seeing the oil paths, I am baffled (pun intended) as to why right turns don't allow for oil to return in enough volume back to the intake.

I should have noted more prominently: I have no background in fluid dynamics. I know enough about the concepts of cavitation and boundary layers to know that it is very difficult to develop an intuition about them that matches real-world behavior.

The primary goal of my initial video was just to point out that this problem is observable with the right instrumentation and that I believe these pressure drops are cause for concern. Everything beyond that is an unproven hypothesis.

[mpg9999]

Originally Posted by Blighty

Interestingly just noticing that the design in the BRZ technical changes document from Subaru shows a different layout of the chain cover than what you are showing.

Very strange - wondering what's going on here.

Yeah, that is really strange.

@KillerBMotorsport, is that a timing cover you pulled from an FA24? How crazy would it be if Subaru somehow used the wrong drawing or there was some manufactoring mistake and those ribs were accidentally excluded.

[Blighty]

Originally Posted by mpg9999

Yeah, that is really strange.

@KillerBMotorsport, is that a timing cover you pulled from an FA24? How crazy would it be if Subaru somehow used the wrong drawing or there was some manufactoring mistake and those ribs were accidentally excluded.

It could be a difference between the FA24F and FA24D...

There are other slight difference apart from the missing ribs as well.

[makinen]

Originally Posted by drift86

I'll like to see the Greddy baffle tested. It has a plate that sticks up that is designed to prevent oil from going into the front chain cover.

6 months old video is there.

[FrickingReallySlow]

Do you have a link to this technical changes document?

Originally Posted by Blighty

Interestingly just noticing that the design in the BRZ technical changes document from Subaru shows a different layout of the chain cover than what you are showing.

Very strange - wondering what's going on here.

[FrickingReallySlow]

Its really the design of the upper oil pan/oil pickup (not timing cover) that's the defining difference between the oil sloshing movement on track. the first 2 pics on the Gen2, you can see that there's a huge void in the upper oil pan as well as the way the oil pickup is skinny right where it goes into the timing cover that provides a huge passage for oil to move into.

Compare that to the Gen1 picture (my car with killerB pickup) the giant casting and giant oil pickup mating surface basically blocks the majority of the pathway for oil to get into the timing cover. The casting and mating surface of the oil pickup is also at a lower level (mating surface level of the lower oil pan) which would act as a lower baffle just by itself.

[Blighty]

Originally Posted by FrickingReallySlow

Do you have a link to this technical changes document?

https://drive.google.com/file/d/1hQX...ew?usp=sharing

[Blighty]

Originally Posted by FrickingReallySlow

Its really the design of the upper oil pan/oil pickup (not timing cover) that's the defining difference between the oil sloshing movement on track. the first 2 pics on the Gen2, you can see that there's a huge void in the upper oil pan as well as the way the oil pickup is skinny right where it goes into the timing cover that provides a huge passage for oil to move into.

Compare that to the Gen1 picture (my car with killerB pickup) the giant casting and giant oil pickup mating surface basically blocks the majority of the pathway for oil to get into the timing cover. The casting and mating surface of the oil pickup is also at a lower level (mating surface level of the lower oil pan) which would act as a lower baffle just by itself.

Sure.

Just trying to understand what going on. Because it does look like its not the FA24D timing cover as detailed by Subaru anyway. The upper oil pan is a little more difficult to properly match from the documentation as its a weird angle, but it looks far more similar (even though they do note a few changes to it as well).

[vindiesel]

Doesn't’ the wrx using the same engine essentially. Shouldn’t they have the same if not worse problems then the brz given the oil lubricates turbo as well plus more heat? (I know less people autocross these as well)

[ZDan]

Originally Posted by 900BRZ

Hi, just wanted to share some preliminary testing I’ve been doing to set a baseline before installing the prototype baffle.

The prototype baffle is going on my car today and I’ll be at Thunderhill 5-Mile on July 1 to test the baffle.

You are doing the Lord's work! Thank you...

I had local Subie dealership (with great techs who are knowledgable enthusiasts) inspect for RTV, they found a bit (small amount relative to some pics I've seen) but enough that they agreed that inspection/removal would be warrantied.

I just ran NJMP Lightning on Monday/Tuesday (won my class in time trials!), which has both an extended and banked right-hander (turn 9) as well as two right-handers with big elevation changes, turns 1 and 5 both are sharply uphill from turn-in up to a peak near apex and then sharply downhill. I tried to minimize laps throughout the event while ensuring I was on top of competition who was lapping 2x more than anyone else!

Looking forward to seeing results with the baffle...

[KillerBMotorsport]

Originally Posted by vindiesel

This video needs stickied…I know a baffle would be cheaper then this. A remade oil pan and the deeper part centered with oil pick up tube? Or a deeper high capacity oil pan to insure no drop? Even if oil is getting trapped in other parts of the engine extra capacity would negate the pressure drop would it not? Or hell a pick up tube that has a bend center of the current oem oil pan?

We have made a couple attempts at making higher volume oil pans for the FA platform. There is very little room for the pan so expanding the volume didn't result in any significant increase. Certainly not enough value to the customer that I would feel comfortable charging for.