Oil Control In Rb's For Circuit Drag Or Drift

[chairman]

need some advice ,

would it be good or crap idea to remove the factory baffle plate and run the rear breathers stright to sump for oil drain, and weld 2 x-12 at the front of rocker cover to oil catch can ?

9l sump -

oil catch can drain to sump

i seen this setup on the single cam rb30

thanks gerasimo

[The Bogan]

need some advice ,

would it be good or crap idea to remove the factory baffle plate and run the rear breathers stright to sump for oil drain, and weld 2 x-12 at the front of rocker cover to oil catch can ?

9l sump -

oil catch can drain to sump

i seen this setup on the single cam rb30

thanks gerasimo

No, you need the baffles to knock out the oil.

It might work for the street but I dare say it would be a fail at the track

[abr33]

Im trialing my idea with it all, I made my sump it holds 7.5 liters, gated and baffled, better pickup, 1 inch hose from r/h side of sump at top, to the cam cover, read head drain, drilled oil returns in head and block, 1.3mm restrictors ( i recon 1mm after crush). Also have the factory breather positions, modified the baffle plates in covers to resist oil flow, also have s/s superfine mesh holding in s/s wool, with breathers going to catch can, and a half inch hose from bottom of catch can to exhaust top side of sump, in the catch can i have a baffle plate, with foam filter offcuts in breather side to stop oil mist.

Also running tomei pump set at about 70 psi, with redline 15w/50 oil.

No idea how it'll go on a track but so far i get mist go into can as the little oil that stays in can looks very dirty, im assuming not alot passes through..

If anyone want pics of anything iv done (except can as i have none yet) I can post the relevant pics..

[kitto]

What have people done to easily modify and improve the baffling in RB25 cam covers?

The RB26 ones are good as you can just buy the MINES kit, but with a factory plenum you can't fit RB26 rocker covers as they are too tall.

Has anyone done an effective, easy and cheap modification to the cam covers? Unfortunately the RB25 baffles and riveted in making it a bit difficult to disassemble.

The covers are one of the last things i need to look into for my oil control.

[abr33]

What have people done to easily modify and improve the baffling in RB25 cam covers?

The RB26 ones are good as you can just buy the MINES kit, but with a factory plenum you can't fit RB26 rocker covers as they are too tall.

Has anyone done an effective, easy and cheap modification to the cam covers? Unfortunately the RB25 baffles and riveted in making it a bit difficult to disassemble.

The covers are one of the last things i need to look into for my oil control.

I have, tigged bits inside, removed rivets, put in m4 s/s allen screws.., also made s/s wool pillows under breather holes

[abr33]

pics..

[kitto]

pics..

Nice work mate. Did you notice a considerable difference after you did this mod? Or did you change a lot of things at once and couldn't really tell?

Whats the big extra outlet for? I'd like to do something like this, disassembling the covers and tapping them out to M4 isn't too hard for me, but any aluminium or stainless welding is a bit harder having no TIG or TIG skills.

[abr33]

Thanks, the big one is for my sump breather.. I did everything at once. first build not knowing about any of this with n1 pump, light oil, stock sump restrictors etc it was a filthy oil spewing mess. What I did with covers is to try interfere the air flow to pull the particles of oil that come past.

Also got pics of my sump and other bits if needed..

[kitto]

Ahh ok yep.

I've pretty much got the entire rest of the oil system sorted. Massive sump is done.

I'm now down to how to set up the cam covers and the catch can(s).

[Bushy]

I'm sure this has been asked but I don't have time to read all 44 pages (I have already done a search on this thread).

What is the standard restrictor size in an RB25DET (series 2)? Some people say 2mm some say 1.5mm, we have our head off at the moment and there are 1.5mm restrictors in it but I have no idea if previous owner put them in or they are standard.

Cheers,

Michael

[JonnoHR31]

1.5mm is standard for RB25s. The only RB to come standard with 2.0mm feeds is RB30.

[Bushy]

Awesome, thanks mate!

[STATUS]

Never drain catch can back to sump. Anyone who has done an oil analysis from catch can residue will also concur.

If your excuse is that your passing enough oil into the catch can and you need to drain it back.... then you have more than contamination issues to worry about.

[Johnny_B]

i would be interested to see as many pictures of peoples sumps as possible.

my rb25 will run:

• a stainless steam pipe copy of a trust manifold,
  
• t67-25g
  
• rb26itb's
  
• no vct
  
• larger cams and cam gears
  
• rebuilt head with spings & retainers, relapped valves, new seals
  
• arp head studs
  
• standard nissan headgasket.
  

rev limit will be limited to around 7500rpm with the standard bottom end. motor will be tuned on 98 for now e85 in the future.

the car is essentially a drift car, however will be used for other events such as club sprints, hill climbs, motorkhana's as well as spirited hills driving

my oil control mods atm are:

• standard oil pump
  
• cylinder head drain, draining back to exhaust side (im now reading this is more of a vent than anything)
  
• having a custom winged and trap door sump made. hopefully 1-2l larger than standard however i can only go wider not deeper due to ground clearance issues.
  
• oil cooler with greddy thermostatic sandwich plate
  
• -10an fittings welded to standard vent location on valve covers
  
• vented to atmo catch can (no return to sump)
  
• blocked pcv
  

now to block the vct my engine builder/engineer and myself were thinking we would use a grub screw to block the vct feed in the block

make a grub screw to cap off the vct solenoid.

and to feed oil to the front of the cam drill into the brass plug in the oil gallery and take the feed from the gallery?

the head is currently off and disassembled

im now thinking i should do the following things:

• remove the baffles from cam covers, fit steel wool under fitting, and cap screw the baffles back in place?
  
• fit a sump vent -10an from sump to catch tank on exhaust side
  
• remove crank, machine, new bearings and fit a crank collar
  
• drill oil return galleries in head and block
  
• fit oil restrictors the guide says to block one and fit a 1.25? i would be doing it by means of grub screws not the tap in ones. does anyone have any results with doing this?
  
• would also consider fitting billet gears to my standard rb25 pump
  

any answers or experience would be greatly appreciated and if i need to provide any more information so anyone can help me i will do so asap.

thanks, john!

[NoFigJamHere]

Never drain catch can back to sump. Anyone who has done an oil analysis from catch can residue will also concur.

If your excuse is that your passing enough oil into the catch can and you need to drain it back.... then you have more than contamination issues to worry about.

So does that mean every dry sump system is wrong?

[R32 TT]

So does that mean every dry sump system is wrong?

yeah I wondered the same thing. Surely the oil that blows out of the top of the motor (instead of draining straight back down through oil galleries), and goes directly to a catch can, which then drains directly (and immediately) back to the sump is kind of the same thing? Its simply taken a detour..?

[The Bogan]

Oil that just sits in catch can will accumulate all the moisture in the system due to it only staying warm enough the attract moisture and will turn to crud, but if it drains back to the sump from the catch the moisture will be cooked off in the hot oil, my can has been returning to the sump for a couple of years now with no ill effect

The vents on top of the catch can allows any moisture in the system to get out.

Simples physics like me, simple...

[abr33]

So does that mean every dry sump system is wrong?

yeah I wondered the same thing. Surely the oil that blows out of the top of the motor (instead of draining straight back down through oil galleries), and goes directly to a catch can, which then drains directly (and immediately) back to the sump is kind of the same thing? Its simply taken a detour..?

I can confirm, today i got my oil report, in 2500kms with my can draining to sump, and having done probably 8 hours driving in rain and heavy fog/freezing temps etc my water content is over double the acceptable level. (0.087%) the acceptable is 0.03... Not a massive amount but definately alot. summer might be better... I might block my sump drain..

[The Bogan]

I can confirm, today i got my oil report, in 2500kms with my can draining to sump, and having done probably 8 hours driving in rain and heavy fog/freezing temps etc my water content is over double the acceptable level. (0.087%) the acceptable is 0.03... Not a massive amount but definately alot. summer might be better... I might block my sump drain..

Water comes from the atmosphere and the combustion of fuel, one of the byproducts of fuel burning is water, sounds silly but its true, a forged motor will breath heavier until it has come up to temp and allow more contaminants to get past the rings.

Same with higher boost, there are some good research papers on this in the interwebs.

And E85 will produce even more moisture.

Ill look for some linkys on this later IICBA

[The Bogan]

Water %

Percentage of water found in sample given as a percentage of total volume. Moisture is common in short trip vehicles that don’t fully get the oil up to operating temperature long enough. It generally takes 10-15 minutes for the oil to get to this temperature, which is enough to start evaporating the moisture in the sample. The same goes for fuel in your sample too. An occasional long highway drive is good for your oil’s health.

http://www.bobistheo...e-oil-analysis/

Also, if you run your cars oil at over 70 deg for 30 to 40 min it should burn off any moisture that has accumulated in the oil