[Adam Way]

Tibra1, I didn't take your message as anytihg other than providing educational discourse on a subject that to the best of my knowledge hasn't been discussed in this way on this forum as of yet. I think it is awesome you have a set-up you like and works well. Thanks for chiming in and helping me out.

[ultimateracing335]

I'm also burning oil but it's reduced since removing my catch. I've installed a new check valve but have seen no difference. Hoping a fix comes soon cause it's embarrassing getting smoke from a car with well over $80000 Canadian invested in it.

[vasillalov]

Same thing here on stock turbos. I have a fully divorced exhaust setup and you can easily see more soot on the left tail pipe. I am burning through about 1 quart every 500 miles which is a lot. It all started after I removed my BSH OCC. I think this would be just a coincidence though.

I uninstalled my Cobb AP and took it to a very trusted SA which I often go to AutoX events with. They kept the car for 4 days and could not replicate the problem.

I am starting to believe that this oil consumption only occurs under higher boost.

[tibra1]

Originally Posted by vasillalov

Same thing here on stock turbos. I have a fully divorced exhaust setup and you can easily see more soot on the left tail pipe. I am burning through about 1 quart every 500 miles which is a lot. It all started after I removed my BSH OCC. I think this would be just a coincidence though.

I uninstalled my Cobb AP and took it to a very trusted SA which I often go to AutoX events with. They kept the car for 4 days and could not replicate the problem.

I am starting to believe that this oil consumption only occurs under higher boost.

What you have is probably failing turbo seals..which unfortnutaly means u need new turbos…when my time comes I will pick up new stock turbos from these guys..$555/each

www.bmwpartscenter.net

[Rob@RBTurbo]

1) OCC's definitely are causing an adverse affect on some vehicles with upgraded turbos, and personally I recommend they are not equipped until more is known exactly why. This is not much of a drawback as the way they are being installed and designed these days is certainly flawed anyhow (see PCV saga thread for more info there, there is a ton of info over there). Removal in itself of the OCC units make a drastic change nearly everytime they are pulled, so there's something to be said for that (ie. it is causing unnecessary problems). Although I'd agree the better units only cause a minor restriction, it only takes a minor restriction to defy the gravity draining in turbos which is where I believe the problem manifests itself. There is some likelihood there is a deficiency in the unique PCV system the N54 employs to support this amount of engine load as well, but I'm not ready to conclusively say that quite yet even though there are some indications that suggest as such (ie. oil notoriously dripping from rear induction tube from the check valve on the valve cover).

2) The CHRAs in these turbos (and the original units or all turbos for that matter) were designed to work under a certain range of oil feed pressures, exhaust pressures on the turbine side, and draining ability. Relieving the exhaust backpressure can cause seals to seep more oil and cause smoke/smell/oil consumption. You may say, "well my original units did not have any problem even with open exhaust, why these?". I believe the RBs are more susceptible to said input oil pressure and flow may need to be restricted- especially in those situations where exhaust is very free flowing. Here is why: Lack of exhaust backpressure from the modified turbine housings (something your originals didn't have) PLUS efficient extremely well flowing post turbo exhaust systems can cause an increased disparity in pressure between oil internal CHRA and exhaust at the turbine outside seal (oil stays consistent, exhaust pressure goes toward nil) which allows more oil seepage at low load conditions. The dynamic seals seem to keep the oil in the turbo as they are in boost or high load, as they should. At low load, you have a much larger turbine bore plus a wastegate flapper (which pending on the software can be more or less open and free flowing as another factor) which does not help maintain oil from escaping, compile that with a potential unnecessarily over pressured oil inlet, it can causes seepage. Add in a restrictor (ie. OCC) in the PCV it even makes things worse as the intake channels have to pull through it to get the fresh air from the Induction inlets, which raises crankcase pressures and further affects turbo drains. Also low load drawbacks of OCCs I do not believe were ever tested, as at the time it seemed less important. But their low load impact maybe more than once thought, as feedback suggests significant improvement upon their removal.


In summary it is my thoughts that some combination of high oil feed pressure (which can be affected by oil viscosity, engine bearing tolerances, oil pump output, oil temps, etc), slow gravity draining (which can be affected by PCV alterations, overfilled crankcases, oil temps and viscosity, excessive blowby), free'er flowing modified turbine housings and exhaust (caused by modifications that we obviously want to support big horsepower), and possibly some others I can not think of at the moment (ie. even driving behavior or patterns)- appear to on occasion cause some to encounter this condition. To add confusion though, there are some who do everything non-textbook (ie. defy all above) and have no problems at all.

So in a nutshell Adam if the OCC removal in itself doesn't remedy your situation, you may need an oil feed restrictor. There is no restrictor on the N54 and the oil feed lines are likely significantly oversized, so it very well could be a next course of action. Oddly enough this doesn't seem to affect all of those who run RBs; but the frequency is becoming to be enough to consider further options. Dzenno is correct in that we just don't want to throw in a restrictor without at least SOME knowledge on how the N54 operates with oil pressure, not to mention many other potential variables- but at this point I am left to believe that the N54 has a very high oil pressure operating range which under certain conditions can cause engineering guidelines to be crossed.

There also seem to be those who have "certain conditions met" on OEM turbos that may be crossing some engineering guidelines as well, as it is very often where those with the OE Turbos that otherwise perform properly add a free flowing exhaust only to begin getting smoke/smell/or oil consumption. It's nearly an everyday thread where someone encounters this and that is chalked up to "bad turbos" that were "good" the day before the exhaust mods. I am not so sure that is the case and it is leading me to believe the car was designed at some high threshold of engineering limits. Close enough to the edge to where some have problems and some do not based on a wide array of variables that can make enough difference to put vehicle 1 under and vehicle 2 over. If the theory is correct, then it only makes sense that RBs will have even more of a disparity due to the much enlarged and free'er flowing housings- but if holds true we may also find that a restrictor maybe beneficial for those who encounter the problem with OEM Turbos as well.

Rob

[jippii ensio]

Slightly added oil consumption enables one to fill in more fresh oil to fight the oil contamination due to the water-methanol injection.

[Syndicategt]

Great post Rob....I was getting worried there for a minute. I'm one of those OEM guys with a very free flowing exhaust (AR 3" DP's + AE exhaust) who ocasionally gets smoke when idle.

I've noticed lots of issues with this free flowing setup, stock and otherwise. I wonder if switching back to the OEM exhaust (keeping the aftermarket downpipes) might help aleviate the issue. I know the cats would mask it, but like you said, there will be more backpressue.

[dzenno]

Originally Posted by jippii ensio

Slightly added oil consumption enables one to fill in more fresh oil to fight the oil contamination due to the water-methanol injection.

well, that is a bonus for sure lol

[Clap135]

I have 55k, stock turbos obviously, fully bolted, meth for over 45k, never once did I have to add a drop of oil. I also have been using a catch can for most of those miles, various ones in fact and never had any issues with smoke.

[jippii ensio]

Originally Posted by dzenno

well, that is a bonus for sure lol

Well, I must admit though that the extra power and fixing my wastegate rattle as the one and only turbo upgrade available, were even bigger factors in my RB purchase decision

[CPWINCH]

Originally Posted by Clap135

I have 55k, stock turbos obviously, fully bolted, meth for over 45k, never once did I have to add a drop of oil. I also have been using a catch can for most of those miles, various ones in fact and never had any issues with smoke.

Nice to see your back

[tibra1]

Originally Posted by Clap135

I have 55k, stock turbos obviously, fully bolted, meth for over 45k, never once did I have to add a drop of oil. I also have been using a catch can for most of those miles, various ones in fact and never had any issues with smoke.

+1 except I have 20K Miles n no meth

[dzenno]

Originally Posted by Clap135

I have 55k, stock turbos obviously, fully bolted, meth for over 45k, never once did I have to add a drop of oil. I also have been using a catch can for most of those miles, various ones in fact and never had any issues with smoke.

Sure, and that's cool..that was my case as well...we're actually trying to figure out why we do have oil consumption/smoke issues and how to deal with it...what's your take on it?

Originally Posted by jippii ensio

Well, I must admit though that the extra power and fixing my wastegate rattle as the one and only turbo upgrade available, where even bigger factors in my RB purchase decision

extra power is intoxicating that's for sure...we just have to figure out what's causing the oil consumption/smell/slight smoke on some RB installs

[Clap135]

Originally Posted by dzenno

Sure, and that's cool..that was my case as well...we're actually trying to figure out why we do have oil consumption/smoke issues and how to deal with it...what's your take on it?



extra power is intoxicating that's for sure...we just have to figure out what's causing the oil consumption/smell/slight smoke on some RB installs

Its the turbos, the seals blow in some of them in my opinion. I don't own them so I can't comment, however was a flow chart ever provided for them. What kind pressures can they handle without blowing? It's no secret whoever upgrades to aftermarket turbos runs them hard at 18-20 psi, question is, is that blowing them? If they were in there optimal range you would be holding boost to redline and also making max power at redline, which is not the case.
Personally, as more and more people upgrade to reworked stock type turbos, more of these problems will be voiced on the forums.

If i ever ditch the stock turbos, it wont be for reworked ones, it will be for a single or something like gt25/28 twins, but that wont be for a long time, if ever.

We already had a debate way back in that pvc saga thread, and my opinion still stands, that small restriction is laughable and not the cause, but do your own thing and believe what you want.

If rob states that it might be an oiling issue and lack of a restrictor, then a proper feed line should be provided with the upgrade. Btw I also don't believe this, but I also don't have any experience on the matter.

When I upgraded my last car with a gt35r, I ran off the shelf oil feed/return lines and never had any issues with smoke or oil consumption.

[Elie335]

Originally Posted by Clap135

Its the turbos, the seals blow in some of them in my opinion. I don't own them so I can't comment, however was a flow chart ever provided for them. What kind pressures can they handle without blowing? It's no secret whoever upgrades to aftermarket turbos runs them hard at 18-20 psi, question is, is that blowing them? If they were in there optimal range you would be holding boost to redline and also making max power at redline, which is not the case.
Personally, as more and more people upgrade to reworked stock type turbos, more of these problems will be voiced on the forums.

If i ever ditch the stock turbos, it wont be for reworked ones, it will be for a single or something like gt25/28 twins, but that wont be for a long time, if ever.

did you mean like ?

[Clap135]

Originally Posted by Elie335

did you mean like ?

Hard to say what you go there based on that picture. Maybe this has been discussed previously but I havnt been following the forums all the much latly. Get a vband exhaust housing though, some of those dp bolts look like a major pita lol

[Elie335]

Originally Posted by Clap135

Hard to say what you go there based on that picture. Maybe this has been discussed previously but I havnt been following the forums all the much latly. Get a vband exhaust housing though, some of those dp bolts look like a major pita lol

TD04L, I haven't made any thread on the forum about this, just some members around here knows what's going on.

I'm already running these turbos for a while now, car running strong at 14 PSI with a custom ESS flash tune.

tough, I'm consuming quarter oil every 700 miles or something.

PS: TD04L got the same size as a garrett GT28.

[themyst]

Originally Posted by tibra1

What you have is probably failing turbo seals..which unfortnutaly means u need new turbos…when my time comes I will pick up new stock turbos from these guys..$555/each

www.bmwpartscenter.net

My car threw a low oil pressure code and I was dangerously low on oil out of the blue with no warning. I topped the oil off one quart and 1000 miles later, it needs another quart.

Hard to imagine the turbos going out at 22k miles but funnier things have happened.

[dzenno]

Originally Posted by Elie335

TD04L, I haven't made any thread on the forum about this, just some members around here knows what's going on.

I'm already running these turbos for a while now, car running strong at 14 PSI with a custom ESS flash tune.

tough, I'm consuming quarter oil every 700 miles or something.

PS: TD04L got the same size as a garrett GT28.

WHAT??? you got them running already? Nice man...what's the plan on a lengthier update than that photo? Was there a reason you stopped at 14psi? What're the differences between those, stock and current upgraded turbo offerrings? Which TD04L is it, have specs? Way too many questions lol

[Clap135]

A td04 will die up top as well, have you pushed the car yet?

[Rob@RBTurbo]

Look like TD04L-13Ts, slightly smaller than RBs in wheel size. Good upgrade, but if going full upgrade route would likely use something else. He maybe able to benefit from this discussion though, regarding oil consumption.

[Elie335]

Originally Posted by dzenno

WHAT??? you got them running already? Nice man...what's the plan on a lengthier update than that photo? Was there a reason you stopped at 14psi? What're the differences between those, stock and current upgraded turbo offerrings? Which TD04L is it, have specs? Way too many questions lol

yeah, I got them running lol , I'm currently waiting for a custom TMAP sensor and another custom MAP from ESS so I could push these turbos more then 14 psi. I'll PM you tomorrow with more updates pictures

Originally Posted by Clap135

A td04 will die up top as well, have you pushed the car yet?

not yet, I do NOT trust any piggyback to test these turbos more then 15 PSI even with RACE GAS and meth, I'm waiting for ESS flash or ATR by cobb.

Something to be added, THESE turbos DO NOT die on high RPMS, remember, they're TD04L and not TD04.