R32 Sedan - Grip and Drift (have my cake and eat it too build)

[CRSKmD]

Welp, too late already committed to the cam cover breathers to be welded on.

I did think about adding a catch can in line with the drivers side sump breather as a phase 2 along with a drain to the sump on the original catch can but with an inline ball valve so I can have it closed if needed. 
 

Likely a single breather would have been enough but I think I’m overcompensating to hopefully not have to empty my catch can and clean up oil over flow every session. 
 

out of curiosity has anyone actually measured crank case pressure before and after various mods? I’m considering adding a sensor for science 

[Kinkstaah]

I just used a can that's easy to empty after every session and pour it back into the fill hole. Takes about 40 seconds when you have 40 minutes between runs :p

I don't see how changing any catch can stuff will reduce pressure if the system is sealed. And if it's vented - Does it matter where it's vented with regards to overall pressure?

[GTSBoy]

1 minute ago, Kinkstaah said:

I don't see how changing any catch can stuff will reduce pressure if the system is sealed. And if it's vented - Does it matter where it's vented with regards to overall pressure?

Yeah - the secret learned a long time ago is that the RB likes to belch oil out the covers, and/or starve the pump because it drowns the head in oil, because the upflow of crankcase gases from piston blowby comes up through the oil drain holes in the block and prevents the oil from flowing back down.

The external vents from sump are about creating an alternative path/much more XS area for gas flow to decrease the gas velocity up through the oil drains and allow the oil to get back down.

So, it's not about pressure at all. It is about flows - gas up and oil down - or when it's not working, gas up and oil not going where it is supposed to after it arrives at the top, except out through the cam cover vents. And regardless of whether the catch can is vented to air or vented to the turbo inlet, it must still be vented because a sealed system would blow out the crank seals, or something equally bad.

[CRSKmD]

5 minutes ago, Kinkstaah said:

I just used a can that's easy to empty after every session and pour it back into the fill hole. Takes about 40 seconds when you have 40 minutes between runs 😛
 

my catch can is pretty easy to empty but it overflows due to the blowby/crank case pressure etc.
max I have drained is ~600ml even with a ~2.3L capacity. So it is not just about having to drain it out its the mess it makes down the firewall and under the car and rear passenger tyre from the overflow oil being blasted by screamer + air in general.

Ending up on the ground cleaning the oil up and having oil on your arms when everyone else can chill and watch the other sessions gets old fast

[joshuaho96]

2 hours ago, CRSKmD said:

my catch can is pretty easy to empty but it overflows due to the blowby/crank case pressure etc.
max I have drained is ~600ml even with a ~2.3L capacity. So it is not just about having to drain it out its the mess it makes down the firewall and under the car and rear passenger tyre from the overflow oil being blasted by screamer + air in general.

Ending up on the ground cleaning the oil up and having oil on your arms when everyone else can chill and watch the other sessions gets old fast

Seeing just how complicated you're making this is kind of terrifying to me. I would not want this level of hoses running all around the engine. I also am a fan of draining back to sump by default.

[CRSKmD]

3 minutes ago, joshuaho96 said:

Seeing just how complicated you're making this is kind of terrifying to me. I would not want this level of hoses running all around the engine. I also am a fan of draining back to sump by default.

not something I originally wanted to do. My plan was to just add the cam splash shields. This is the result of speaking with a few people in both time attack and drifting that have RB's making the same or more power than mine with the same issues. Using their experience and advice for what has actually worked in a similar application (sustained high RPM, long sweeping corners).

They all have had at least an additional head sump drain breathers on top of the rear of head welsh plug drain/breather.

I wouldn't do this for a car that's only street driven even my current setup has been sufficient for street duties.

[MBS206]

One of the big things people mess up to, is the location of the ports on the sump.

Add them in one spot, and the movement of everything in the crankcase makes it hard for oil to drain down there. Place it in another area, and it aids it.

Same sort of issue with the cam covers. One side of drain holes is copping it hard from air movement pushing up.

 

Also, if your catch can has a 2.3L capacity, and you've only ever drained 600ml of oil out of the catchcan, yet the catch cans breather has puked oil everywhere, fact of the matter is, your catch can is doing a shit job of oil/air separation, and a massive improvement alone would just be in a better catchcan design.

[GTSBoy]

25 minutes ago, MBS206 said:

fact of the matter is, your catch can is doing a shit job of oil/air separation, and a massive improvement alone would just be in a better catchcan design.

That too, but I think this is why she's put the work into the cam cover baffles. I mean, a catch can should only need to be a catch can, not an oil air separator also. Not to say that putting the effort into having it do a better job of oil-air sep is a waste of time, but doing the sep earlier is always going to make life better. And that should happen now anyway.

[CRSKmD]

I think the catch can design is pretty flawed. Evident in the fact that the V2 one moved to a larger top mounted filter which alone would have helped with overflow and reduce restrictions compared with the side filter. I also imagine there was a major improvement to the baffling design.

It is worth mentioning that this catch can with the RB20 was never as much of an issue and the high kms RB25 is likely a part of the problem.

I have gotten quotes for both a new "Vibrant Gen 3" catch can and to modify this existing ones but that may have to wait until after the track day. I hope the sump/head breathers/drains and cam splash plates will be enough

[MBS206]

1 hour ago, CRSKmD said:

I think the catch can design is pretty flawed. Evident in the fact that the V2 one moved to a larger top mounted filter which alone would have helped with overflow and reduce restrictions compared with the side filter. I also imagine there was a major improvement to the baffling design.

It is worth mentioning that this catch can with the RB20 was never as much of an issue and the high kms RB25 is likely a part of the problem.

I have gotten quotes for both a new "Vibrant Gen 3" catch can and to modify this existing ones but that may have to wait until after the track day. I hope the sump/head breathers/drains and cam splash plates will be enough

Shove more foam in it as a minimum if you possibly can. Or steel wool (not the stuff with soap on it!)

Baffles / getting the oil out of the air is huge, and should be done at both the cam cover, and the catch can.

 

I'm about to do a power steering reservoir, and even that needs some thought to make sure air is separated from the oil, to stop evil Cavitation.

I'll probably look at doing my own catchcan later on too.

[CRSKmD]

1 hour ago, MBS206 said:

Shove more foam in it as a minimum if you possibly can. Or steel wool (not the stuff with soap on it!)

Unfortunately there is no way to properly access the baffles. It’s a welded unit and the inlets and drain are too small to jam anything down realistically. Same with the breather I took off the cover and foam and it’s basically a wall

[CRSKmD]

I got the four AN10 fitting welded up to the cam covers and started up making the head to sump breather/drain lines.

The front passenger side cover I used a 45 up top and a 90 at the bottom into the stock VCT head drain spot (3/4" BPST to AN10 adapter) thats unused on the RB25DET NEO with some speedflow flame shield to protect it from the manifolds heat.

 

back passenger side was a 90 up top with some flame shield and 45 at the sump end.

The rear drivers is 45 at both ends

 

the front drivers fitting is capped off for now but ready to go if i want to try moving the breathers around.

I was told by the fabricator to leave all the welds raw for now to make sure there are no pin hole leaks.

A lot of cleaning up, re bundling looms and degreasing to go as well as final assembly on the cam cover baffles.

The first real test will be 28th March at a Circuit event.

added complexity and more spots for leaks but overall looks relatively neat imo

[GTSBoy]

Yeah, thumbsup from me. The distant shot of the bay just looks same-same as before.

[MBS206]

Good work. I will say, this line circled however, will potentially pool with oil, as it's going from high, to low, to high, before heading downwards.

[CRSKmD]

6 minutes ago, MBS206 said:

Good work. I will say, this line circled however, will potentially pool with oil, as it's going from high, to low, to high, before heading downwards.

Yeah good call, I will endeavour to tuck that down when I rewrap the looms it’s pushed up by

[CRSKmD]

Got just the wing painted and fitted up to the existing boot. Big visual change and about time after having a GTR wing sitting in the shed since 2018

Headed up to Mallala with a quick obligatory stop in at Boliver OTR

Oil control mods seems to have worked. I checked the catch can after session 1 and there was a dribble of water/e85 with barely any oil in it. After session 2 and 3 there was almost nothing and I stopped checking after that. so either great success or catastrophic failure/block of the external breather

The GTR wing made a noticeable difference in the 160-185km/h sweepers.

It was a very hot day for the cars at over 33C but the previously done cooling upgrade/ducting/water sprayers meant I never saw over 60C intake, 105C water and 100C oil and temps would drop back down very quickly once I shut it down.

AD09's are a decent tyre but certainly and expectedly a step down when compared the the CR-S/AR-1 I have had on the car for years of track days. The handling characteristics of my car which I often describe using the Tony Hawks Pro Skater balance mechanic where either side of the center is understeer/oversteer was much more pronounced with no "green/safe" zone in the middle. However, imo it steers well/easily during oversteer largely thanks to the custom ACOSTAL front end.

Enjoy a loose lap POV with my mate giggling away as a passenger.

 

Group photo for Peer Pressure Racing

made it back home and gave it a wash

Overall a great success compared to my previous two track days where i cooked the Starlets motor and blew up the new diff in the R32

 

Edited March 31 by CRSKmD