Oil Control In Rb's For Circuit Drag Or Drift

[bigmikespec]

Interesting to note that the Mspeed R34 uses a standard sump, I have read it before and also these photos on their website may confirm it too. I am sure there would be oil mods probably the same suggested by Dirt and others.

[Swiper the Fox]

Are you saying that the fitting on the rhs of performance metalcraft sump is for good for catch can drain back or not?

ok...ill tell you how after much testing ive set mine up.

The rocker covers and the sump vent on the RHS of the Performance Metalcraft sump all run to what i refer to as the intermediate tank in the front corner of the engine bay. This tank allows the liquid 'heavy' oil to return to the sump when the engine is not on boost but most importantly allows the sump and rockers to properly breathe when under boost or positive pressure conditions. The oil misted pressured air runs up the braided -10 line to the tank in the rear of the engine bay where the 'thin' black fuely mist is separated or "scrubbed" from the pressurised air and the air is vented through the K&N filter attached to it. The fuely oil this tank collects is captured in the base of the tank and is discarded...this waste should not be allowed to drain back into the engine.

here's a pic..the intermediate tank is almost out of shot but shows the general idea...it has a fitting on the base of it running to the sump for venting.

Edited June 30, 2009 by DiRTgarage

[GT-RZ]

ok...ill tell you how after much testing ive set mine up.

The rocker covers and the sump vent on the RHS of the Performance Metalcraft sump all run to what i refer to as the intermediate tank in the front corner of the engine bay. This tank allows the liquid 'heavy' oil to return to the sump when the engine is not on boost but most importantly allows the sump and rockers to properly breathe when under boost or positive pressure conditions. The oil misted pressured air runs up the braided -10 line to the tank in the rear of the engine bay where the 'thin' black fuely mist is separated or "scrubbed" from the pressurised air and the air is vented through the K&N filter attached to it. The fuely oil this tank collects is captured in the base of the tank and is discarded...this waste should not be allowed to drain back into the engine.

here's a pic..the intermediate tank is almost out of shot but shows the general idea...it has a fitting on the base of it running to the sump for venting.

I like that idea! rather than stuff more air in the head just vent directly out the block/sump

is there any other internal modification you have done? drilled, honed anything ? engine bay looks spotless too! do you have a link or picture of these sumps? i had some trouble finding a website!!!

thanks.

Edited June 30, 2009 by GT-RZ

[Ramius83]

ok...ill tell you how after much testing ive set mine up.

The rocker covers and the sump vent on the RHS of the Performance Metalcraft sump all run to what i refer to as the intermediate tank in the front corner of the engine bay. This tank allows the liquid 'heavy' oil to return to the sump when the engine is not on boost but most importantly allows the sump and rockers to properly breathe when under boost or positive pressure conditions. The oil misted pressured air runs up the braided -10 line to the tank in the rear of the engine bay where the 'thin' black fuely mist is separated or "scrubbed" from the pressurised air and the air is vented through the K&N filter attached to it. The fuely oil this tank collects is captured in the base of the tank and is discarded...this waste should not be allowed to drain back into the engine.

here's a pic..the intermediate tank is almost out of shot but shows the general idea...it has a fitting on the base of it running to the sump for venting.

BTW, when you say RHS, you mean "intake" side or "exhaust" side......Depends on view of engine from front or when in seating position lol......

And where is it best to locate the drain on the intake side of the stock sump, ie: near rear of sump, on top section of pick-up/front side, on bottom section of pick-up side/front near drain plug, etc.......

Edited June 30, 2009 by Ramius83

[r33_racer]

he means inlet side...i believe when someone refers to the side of an engine, they mean as if seated in the car....its much easier when people just say Inlet or Exhaust side, its more definitive.

Nice setup too, very very tidy...and your venting system idea is tops

Edited June 30, 2009 by r33_racer

[Swiper the Fox]

he means inlet side...i believe when someone refers to the side of an engine, they mean as if seated in the car....its much easier when people just say Inlet or Exhaust side, its more definitive.

Nice setup too, very very tidy...and your venting system idea is tops

It took a bit of testing various set-up's but i believe what we have now is as good if not better than anything available on the market.

yes RHS is inlet side of car.

Hope my findings are able to assist anyone.

Here's a pic of the sump

Edited June 30, 2009 by DiRTgarage

[Sydneykid]

Oh goody, a worthwhile discussion. The best thing about this particular topic is that there is no right or wrong, it's quite simply not black and white. The external rear of head oil drain will also work as a sump depressorisation route depending on the circumstances at the time.

Before we get into the why and wherefores, there are few basic rules I always follow;

1. The drain into the sump must be above the oil level at all times

2. The drain into the sump must be on the LHS of the engine so that the partial vacuum from the crank swing is used to help gravity

3. The drain must be dash 10 or larger

4. The drain must have its own route into the sump, for example I would never ever link it up with a turbo oil return

5. The relevant restrictors must be fitted to the block, different combinations of oil pumps and restrictor sizes will give different results.

6. The engine is built and maintained sufficiently well enough that there isn't excessive blow by.

Keeping the above in mind. There is plenty of evidence to prove that oil will and does flow down the drain to the sump under acceleration. There is an equally large body of evidence that shows the cam covers will fill up with oil if there is no external rear of head oil drain. This is especially evident when the partial vacuum from the crank swing is used to help gravity pull the oil down into the sump. Want to test the oil return? Simply unscrew the return line next time you are filling the engine up with oil and watch how much oil flows through it.

Then, let's explore the alternatives, that being positive crankcase pressure being relieved.. If there is that much pressure needing to be relieved why is it that the dipstick doesn't get blasted out of its tube? Want to test it? How about removing the dipstick and venting the tube into the catch can. That's a fairly easy modification, allows a large quantity of air to vent. Surely much more efficient than a sump back into head vent where the outlet is submersed in oil under acceleration. Think about it, if that is in fact acting as a sump vent, then it would be highly aerating the oil in the cam covers. Then pumping it out of the cam cover vents, which is hardly a good idea. Obviously much worse just when you don't want it, when the engine is under acceleration and a larger quantity of oil than usual is forced to the rear of the head (ie; high rpm and G forces).

So, a quick summary, using the head to sump connection to relieve excessive crankcase pressure is not a good idea as it would force air through the oil in the cam covers. That's why I use it for the superior solution as a supplementary oil return direct to the sump. If you need to vent the sump because you engine is badly built and/or badly maintained then using the dipstick tube is a much smarter alternative. Simply pop the hose off and insert the dipstick to check the oil level as required..

Cheers

Gary

[Swiper the Fox]

Oh goody, a worthwhile discussion. The best thing about this particular topic is that there is no right or wrong, it's quite simply not black and white. The external rear of head oil drain will also work as a sump depressorisation route depending on the circumstances at the time.

Before we get into the why and wherefores, there are few basic rules I always follow;

1. The drain into the sump must be above the oil level at all times

2. The drain into the sump must be on the LHS of the engine so that the partial vacuum from the crank swing is used to help gravity

3. The drain must be dash 10 or larger

4. The drain must have its own route into the sump, for example I would never ever link it up with a turbo oil return

5. The relevant restrictors must be fitted to the block, different combinations of oil pumps and restrictor sizes will give different results.

6. The engine is built and maintained sufficiently well enough that there isn't excessive blow by.

Keeping the above in mind. There is plenty of evidence to prove that oil will and does flow down the drain to the sump under acceleration. There is an equally large body of evidence that shows the cam covers will fill up with oil if there is no external rear of head oil drain. This is especially evident when the partial vacuum from the crank swing is used to help gravity pull the oil down into the sump. Want to test the oil return? Simply unscrew the return line next time you are filling the engine up with oil and watch how much oil flows through it.

Then, let's explore the alternatives, that being positive crankcase pressure being relieved.. If there is that much pressure needing to be relieved why is it that the dipstick doesn't get blasted out of its tube? Want to test it? How about removing the dipstick and venting the tube into the catch can. That's a fairly easy modification, allows a large quantity of air to vent. Surely much more efficient than a sump back into head vent where the outlet is submersed in oil under acceleration. Think about it, if that is in fact acting as a sump vent, then it would be highly aerating the oil in the cam covers. Then pumping it out of the cam cover vents, which is hardly a good idea. Obviously much worse just when you don't want it, when the engine is under acceleration and a larger quantity of oil than usual is forced to the rear of the head.

So, a quick summary, using the head to sump connection to relieve excessive crankcase pressure is not a good idea as it would force air through the oil in the cam covers. That's why I use it for the superior solution as a supplementary oil return direct to the sump. If you need to vent the sump because you engine is badly built and/or badly maintained then using the dipstick tube is a much smarter alternative. Simply pop the hose off and insert the dipstick to check the oil level as required..

Cheers

Gary

Ive ticked all the boxes through 1-6...

My test showed that oil actually comes up the drain under boost and here's your 1-6...it is above the oil level...it is on "your" side of the engine...it is -10...its on its own (using the unused rear oil drain on my single turbo set-up)...i have restrictor in block...its is a new bedded in engine with my tolerances. This was on a street tune with BP98 using only 22psi of boost. We were very surprised to find that this happens as it is the opposite of what we thought would happen. I was intending on running this line to the blocked off -10 fitting you can see on my rear catch can in the engine bay photo above. If i did this id be emptying my catch tank after every pass...now i only do it when i change the oil.

I don't agree with the way the Jap's do it through the head also...yes i agree with one statement you made above. Its much better doing it the way ive done it as it doesn't add any extra air volume or pressure to the head and breather pipes. Thats why ive never done it on any of my own engines and all bar one of the many ive screwed together. Its simply a waste of time.

Ive provided evidence and done actual testing....where is the plenty of evidence you speak of?

Im going to do the clear hose test when i have the time to put this to bed.

Edited June 30, 2009 by DiRTgarage

[GT-RZ]

My understanding was to plumb the external return from the back of the head to the exhaust side on your block/sump entry point....for the reasons i was saying.

Whilst running a wetsump system in our circuit car, we had this oil issue bigtime, catch cans were overflowing, and that was with the 1.5mm restrictor in the head. After that, we ran a even smaller restrictor, and the rear return to the exhaust side of the block/sump. We stopped overfilling catch cans, thank god. But when pulling the motor out on many occasions, everytime the rear return has been holding oil and had leaked out on me when removing that line from under the car. If it were just a vent, then it shouldnt have been able to fill with oil right? Unless in a circuit situation only, it can from holding high revs constantly for 15-20mins straight?

However, i can see the point of venting pressure by running it on the inlet side of the motor instead. If I were still running a wetsump system i would try that out and see how well it works, I can see the theory behind the idea. Especially since the motor is out, it wouldn't be an issue to add a -12 fitting to the sump to plumb it to the inlet side.

hahaha...ok i just read what the jap guy was saying on the other page and see what he said is exactly what i proposed....Only difference is i never considered it being a pressure vent....ahh i should have gone through the previous page...lol

The above must hold some value? perhaps it's a good idea to run a vent from the sump and a return from the head plumbed to the exhaust side of the block??? best of both?

what gary said does get me thinking though. as i remember my old worn CA18 used to pop the dipstick out, obviously relieving some pressure. and it certainly doesn't take much pressure to pop that out?

does anyone have a video of the oil running forward in the head under acceleration? i would like to see this.

[Swiper the Fox]

The above must hold some value? perhaps it's a good idea to run a vent from the sump and a return from the head plumbed to the exhaust side of the block??? best of both?

what gary said does get me thinking though. as i remember my old worn CA18 used to pop the dipstick out, obviously relieving some pressure. and it certainly doesn't take much pressure to pop that out?

does anyone have a video of the oil running forward in the head under acceleration? i would like to see this.

Here's a pic of how the Japs do it.

http://www.skylinesaustralia.com/forums/up...-1150528192.gif

My question...if your removing the line and oil is running out of it its not draining very well is it. After the engine is shut down if its an effective 'drain' wouldn't you think the hose would have no oil in it? Id suggest the oil is coming up the tube from the sump and because of the small fitting in the rear of the head and the oil already in the head there it simply has nowhere to go so remains in the pipe until its removed and runs out the bottom...don't flame me on this one...its just a thought...thats all.

Edited June 30, 2009 by DiRTgarage

[phat_man]

Hi,

on this topic im quite confused. i have a very mildly modded rb20 making around 170rwkw.

attached is how i got the crank case pressure release set up. now after reading abit of this thread i realise that the vacuum should actually go through the head, via the stock vacuum line on the intake plenum.

long story short, where the red lines are, its bunged up. the blue lines, is where i just got some heater hose on, and it just vents to the atmosphere.

is this right? or what should be changed?

thanks.

can someone please answer my question, as im worried this could be un healthy.

thanks.

[Sydneykid]

Let's work on this, one bit at a time;

My test showed that oil actually comes up the drain under boost and here's your 1-6...it is above the oil level

Keep in mind #1 rule

1. The drain into the sump must be above the oil level at all times

The only way oil (not air) can flow up the tube is if it is below the instantaneous oil level. Is it not possible that the oil is actually flowing down from the head but not returning to the sump because the drain is above the oil level at that particular time?

If there is enough pressure to force oil up a dash 10 sized hose then there is more than enough pressure to push out the dipstick. How's your dipstick? Still in place?

Cheers

Gary

[GT-RZ]

I hope we are not elaborating the problem.

If we go back to basics we have an oil pump that is too efficient at pumping oil up to the head. the problem is obviously the return of the oil to the sump.

Without modifying the oil pump we have to restrict the oil delivery and enlarge the oil returns. One of the oil returns originally suggested (sydneykid) was from the back of the head down to the exhaust side of the sump, using the 'vacuum' of the cranks pressure to theoretically 'suck' oil through the return pipe.

The other suggestion was from (Dirtgarage) was to forget about another external return and instead have an additional vent from the intake side of the engine which theoretically would relieve any potential pressure in the sump on the basis that it would minimise airflow through the oil returns and allow oil to return without additional air resistance.

So going by what has been said.

Clearly the pressure inside the case is not evenly distributed because if that was the case the dipstick would be popping out given that this pressure is great enough to largely restrict return oil flow.

so given that there is only one way to prove... tests. i suppose the proof is in the pudding. how many engines have you blown up sydneykid with your mods. how many engines have you blown up dirt with your mods? were they circut, drag? drift?

Edited June 30, 2009 by GT-RZ

[Swiper the Fox]

I hope we are not elaborating the problem.

If we go back to basics we have an oil pump that is too efficient at pumping oil up to the head. the problem is obviously the return of the oil to the sump.

Without modifying the oil pump we have to restrict the oil delivery and enlarge the oil returns. One of the oil returns originally suggested (sydneykid) was from the back of the head down to the exhaust side of the sump, using the 'vacuum' of the cranks pressure to theoretically 'suck' oil through the return pipe.

The other suggestion was from (Dirtgarage) was to forget about another external return and instead have an additional vent from the intake side of the engine which theoretically would relieve any potential pressure in the sump on the basis that it would minimise airflow through the oil returns and allow oil to return without additional air resistance.

So going by what has been said.

Clearly the pressure inside the case is not evenly distributed because if that was the case the dipstick would be popping out given that this pressure is great enough to largely restrict return oil flow.

so given that there is only one way to prove... tests. i suppose the proof is in the pudding. how many engines have you blown up sydneykid with your mods. how many engines have you blown up dirt with your mods? were they circut, drag? drift?

Gary, as always your basis of your point of view is based on theories. I like to put the text books away and do some actual 'real world' testing.

GT-RZ my engines make double the power and in its latest guise triple the power of most lightly modded RB's out there. Revving at up to and sometimes in excess of 9500rpm and over 34psi of boost pressure. Ive never had one of my engines spin a bearing or suffer oil starvation. Yes ive broken 1 N1 oil pump before on an engine but hey...hasn't everyone...this was done banging it of the ignition cut rev limiter at 9500rpm at the drags. Mostly drag, street and circuit engines (never done a drift engine). Gary is a suspension mechanic and uses Harris engines for his builds.

My dipstick stays where i put it after i check the oil. Air travels the path of least resistance...if i blocked the breathers yes it would blow the dipstick out. The oil didn't flow out of the test pipe like a garden hose...it was more in drops flying out the end of it. Next time i dyno the car ill video it for all to see.

Gary will argue his point till he's blue in the face and is not renowned for saying that maybe his theory is flawed...thats just how he is. The testing has been carried out...ive worked out whats best for my engines using several set-ups and ive shared this information with anyone who would like to use it.

Happy motoring

Edited June 30, 2009 by DiRTgarage

[Cjmartz2k]

I don't think anybody is arguing that this mod is a bad thing. To the contrary, the guy that gave me this info, along with my own shop guy both highly recommend it. They just both go out of their way to say that this mod is for gases inside the crank case, especially on really high revving, high boost engines, not oil getting stuck in the head. They both agree there is NO oil getting stuck in the head problem endemic to RB's, stock oil pump or high flow. To be honest, this is the only forum that deals with RB motors that I've ever even heard of this "problem" on.

My point to posting up what I don't think it's the end all be all mod that you must do before you track your car or do a burn out that some people on here make it out to be............and no, that wasn't a shot at anybody, especially SidneyKid--who knows 10x what I know about Skylines. I just disagree on this point.

[Sydneykid]

I'll leave out the personal stuff as much as I can because it adds nothing to the discussion

Gary, as always your basis of your point of view is based on theories. I like to put the text books away and do some actual 'real world' testing.

Not true,

GT-RZ my engines make double the power and in its latest guise triple the power of most lightly RB's out there. Revving at up to and sometimes in excess of 9500rpm and over 34psi of boost pressure. Ive never had one of my engines spin a bearing or suffer oil starvation. Yes ive broken 1 N1 oil pump before on an engine but hey...hasn't everyone. Mostly drag, street and circuit engines (never done a drift engine).

Circuit work is my thing, everyone knows it, so as well as longitudinal G force I have to contend with lateral as well. With just one race representing more revolutions of the crankshaft than a drag engine does in a year. Not sure what that proves other than there is a difference.

My dipstick stays where i put it after i check the oil. Air travels the path of least resistance...if i blocked the breathers yes it would blow the dipstick out. The oil didn't flow out of the test pipe like a garden hose...it was more in drops flying out the end of it. Next time i dyno the car ill video it for all to see.

So it is your belief that there is insufficient pressure in the sump to lift the dip stick. That's not a lot of pressure. If there isn';t enough pressure ot lift the dip stick then there isn't enough to worry about an external vent.

The testing has been carried out...ive worked out whats best for my engines using several set-ups and ive shared this information with anyone who would like to use it.

I have also been testing, probablty since before you were born and this year is my 11th year with circuit RB's. That's a lot of hours of testing.

Cheers

Gary

[Swiper the Fox]

I don't think anybody is arguing that this mod is a bad thing. To the contrary, the guy that gave me this info, along with my own shop guy both highly recommend it. They just both go out of their way to say that this mod is for gases inside the crank case, especially on really high revving, high boost engines, not oil getting stuck in the head. They both agree there is NO oil getting stuck in the head problem endemic to RB's, stock oil pump or high flow. To be honest, this is the only forum that deals with RB motors that I've ever even heard of this "problem" on.

My point to posting up what I don't think it's the end all be all mod that you must do before you track your car or do a burn out that some people on here make it out to be............and no, that wasn't a shot at anybody, especially SidneyKid--who knows 10x what I know about Skylines. I just disagree on this point.

good post...ive said my bit now. This could go on for pages and pages...ill be back in 20 pages time with some more info

[GT-RZ]

This is not an argument, simply a discussion. i like everyone else is just trying to see what's reasonable.

I just can't get in to my head the whole air pressure thing stopping oil return when the dipstick stays put. maybe that could be better explained as so far there is no fact on that in this topic at all, only theory.

What i can understand is small holes and lots of oil in the head and the more holes the easier it will return.

maybe next time someone gets the chance to dyno a 900hp car? they could attach an air pressure gauge to the end of the breathers and in your case dirt block of your vent. see what the max reading is?

although in the end it does not mater so much about the max power, more the horizontal forces acting on the oil coupled with maintained high RPM.

[NickR33]

dipstick is in there pretty firmly... takes MUCH less pressure to move oil around than it would to blow a dipstick out... unless said dipstick has a really worn o ring etc

[Swiper the Fox]

This is not an argument, simply a discussion. i like everyone else is just trying to see what's reasonable.

I just can't get in to my head the whole air pressure thing stopping oil return when the dipstick stays put. maybe that could be better explained as so far there is no fact on that in this topic at all, only theory.

What i can understand is small holes and lots of oil in the head and the more holes the easier it will return.

maybe next time someone gets the chance to dyno a 900hp car? they could attach an air pressure gauge to the end of the breathers and in your case dirt block of your vent. see what the max reading is?

although in the end it does not mater so much about the max power, more the horizontal forces acting on the oil coupled with maintained high RPM.

sure...ill run a sensor in either side of the sump/block and log the pressure readings with the Vi-PEC. Easy.