Oil Control In Rb's For Circuit Drag Or Drift

[-S-]

Yeah i was surprised myself at the very high value. .. oh well. .. but my concern is only why my catch can fills up with so much oil that's all...

[djr81]

If your numbers are all the same except for one cylinder the chances are you have a problem with that one cylinder - ie #6.  So yeah have another go at a compression test but dont be surprised if you have an issue particularly if it is spitting oil.

Edited November 22, 2016 by djr81

[KiwiRS4T]

3 hours ago, -S- said:

So i hesitated to post due to no backed up facts but anyway I just did a compression test and these were the numbers. Stock motor.

P1 - 200
P2 - 200
P3 - 200
P4 - 190
P5 - 220
P6 - 190

And I'm still filling up my catch can easily. .. can i conclude that its just too much oil to the head? Initially i was worried it was due to piston rings ... any thoughts on this? But I'm sure glad the numbers were ok...

What do you mean filling up the catch can easily? You mean with normal driving or on the track? 

If you have broken rings on one cylinder that will do it. Try another compression test and preferably a leakdown test.

[-S-]

Yes filled the can on hard driving. .. man... this sucks... i guess I'll try another compression test else where or order the kit and do it myself. ..

[fatz]

2 hours ago, -S- said:

 

P6 is 150 and not 190...

 

Sounds f**ked

 

drive till it misfires then replace 

[KiwiRS4T]

3 hours ago, -S- said:

Yes filled the can on hard driving. .. man... this sucks... i guess I'll try another compression test else where or order the kit and do it myself. ..

You just need a cheap gauge. Does it blow the dipstick out?

http://www.ebay.com.au/itm/Nice-Portable-Auto-Motor-Engine-Cylinder-Pressure-Gauge-Tool-Compression-Tester-/152311279791?hash=item237675b0af:g:2SsAAOSwKOJYIpT5

or Supercheap or Repco etc

 

[-S-]

Thanks for the link! Was going to ask . Guess u read my mind. And no my dip stick never blows out.

Just thought I'll add...My catch can is connected via the 2 rocker covers--> hose to catch can and vented out.

[GT-R David]

Does anything speak against this setup:

-Hose from right cam cover to catch tank

-Stock Hose from left to right cam cover

-Properly baffled Catch tank vent to atmosphere

And here comes the part I didn't find anything in this thread:

-Hose from AN10/12 fiitting from sump (above oil level on intake side) to existing left cam cover connecting point (which normally goes to intake before turbo).

Should do the trick same as going directly to the catch tank, am I right?

So I can use the existing port on the cam cover, don't need to modify my catch tank and it is a really high point (maybe less blow by than going directly to catch tank)

[KiwiRS4T]

13 minutes ago, GT-R David said:

Does anything speak against this setup:

-Hose from right cam cover to catch tank

-Stock Hose from left to right cam cover

-Properly baffled Catch tank vent to atmosphere

And here comes the part I didn't find anything in this thread:

-Hose from AN10/12 fiitting from sump (above oil level on intake side) to existing left cam cover connecting point (which normally goes to intake before turbo).

Should do the trick same as going directly to the catch tank, am I right?

So I can use the existing port on the cam cover, don't need to modify my catch tank and it is a really high point (maybe less blow by than going directly to catch tank)

 

1. Venting to atmosphere is illegal on public roads and also sub optimal as venting the catch can to the turbo intake can create a small amount of vacuum which helps to vent the sump.

2. It is better for blowby to go to the catch can because the baflles can take out some of the oil.

3. The optimal setup has two hoses going from the sump to the catch can - one to the top and one to the bottom. The latter can act as a drain to allow oil from the catch can to go back to the sump.

4. You don't mention oil restrictors - did you fit any?

There is of course no absolute right and wrong but the above worked for me and a number of others. Some say that a properly built engine will not have oil control problems but RB30s in particular are prone to them.

[GT-R David]

Engine is getting rebuild right now. Will add a Tomei Oil restrictor.

No track days at all. Only Street driving. Only a few kilometers per year. Don't see any need for a drain back to the sump, will empty it if there will ever be a drop of oil in it.

Didn't had a catch tank at all before and had almost no oil consumption, but will make the engine bulletproof this time. I don't wanna do it again.

Quote

-Hose from AN10/12 fiitting from sump (above oil level on intake side) to existing left cam cover connecting point (which normally goes to intake before turbo).

Main question is, will this work as good as going directly from sump to catch tank? Should not make much of a difference?

Edited January 2, 2017 by GT-R David

[KiwiRS4T]

Oil control is usually only a problem when at WOT for a decent length of time such as long straight on the track or extended dyno pull so for a street car you may not experience any problems. Restrictors are a good idea if you have the engine out already.

[Kinkstaah]

I used to have a pretty blowy motor, then I read this thread and hory shet the difference was extreme. What I had previously (even with the stock 1.2mm restrictors in the 34) was in the photo. Would get this kind of stuff after any real kind of RPM's happening.

Blocked one of the feeds, and had the drains enlarged as the head was off at the time. Prolonged revving later (as in.. probably hours of it) and maybe 20ml in the catch can. Enough that it wasn't so much oil as Oil + water vapour, greeny sludge at best.

(I got a fitting for my sump but looking at whats IN the catch can... wouldn't want that going back down there)

In any case, just sharing my experiences with this thread and the help it provided!

[Leroy Peterson]

Geezus, thats a lot to be sitting in the intake...

[GT-R David]

-Hose from AN10/12 fiitting from sump (above oil level on intake side) to existing left cam cover connecting point (which normally goes to intake before turbo).

Main question is, will this work as good as going directly from sump to catch tank? Should not make much of a difference?[/Quote]

No one has a answer for that?

I guess this means nothing speaks against this solution :-/

[GT-R David]

Double post. Sorry

[fatz]

People go from oil cap to sup to ventilate the head

having the vent in the low side of the head( left side to drivers side sump) to the sump seem stupid but give it a shot tell us your results

[NISR32.5]

Thanks for the link! Was going to ask . Guess u read my mind. And no my dip stick never blows out.

Just thought I'll add...My catch can is connected via the 2 rocker covers--> hose to catch can and vented out.

Cracked ringland on the 6th for sure. Exactly the same problem I had with mine.
Unfortunately is engine out and rebuild time

[Rb25/240]

Hey guys great artical about oil restrictors in rb engines. I have a series 1 rb25det I just put in the tomei 1.5 oil restrictor in the middle oil port and blocked off the back one all together my concern is will my hydraulic lifters still be getting enough oil with the rear one completely blocked off and the middle one restricted? Any info would be greatly appreciated

Thanks

[KiwiRS4T]

5 hours ago, Rb25/240 said:

Hey guys great artical about oil restrictors in rb engines. I have a series 1 rb25det I just put in the tomei 1.5 oil restrictor in the middle oil port and blocked off the back one all together my concern is will my hydraulic lifters still be getting enough oil with the rear one completely blocked off and the middle one restricted? Any info would be greatly appreciated

Thanks

Yes

[czy18e]

How much should it cost for a machine shop to open up the oil return galleries in the block?
I thought you could just drill them out with a long 10mm bit but that is backyard spec. What am I missing for over $250