Increasing Oil Pressure on N55 preliminary testing

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Twisted Tuning

Lieutenant
Platinum Vendor
Oct 25, 2016
910
New York
Taking advantage of some of the N55 technological advances here by using the equipped electronic oil flow valve to increase oil pressure wherever we need it.

Defined the table for this a long while ago to control the oil pressure. But just now getting around to actively doing testing.

Testing some moderate oil pressure increases.

Idle (left) - stock was around 40-45psi

Cruise (right) - stock was around 65-70psi

Raising oil pressure for operating temps and even some extent of overtemp oil, and high power operation helps save and maintain bearing clearances and reduces wear and chance of spun bearings on healthy maintained oil.

S55 should have the same thing. So I'll test that also here soon.


IMG_20180425_002548_320.jpg
 
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bahn

Corporal
Nov 5, 2016
111
Davenport, IA
Don't really see the point in doing this Justin. Increasing pressure is not the same as increasing volume of flow, therefor you're not increasing the oil flow through the cooler so you're not lowering operating temperatures. If anything you would technically be increasing temperature. The lower cruise/idle pressures are more than adequate and the high load/rpm pressures are already very very high from the factory.
 

Twisted Tuning

Lieutenant
Platinum Vendor
Oct 25, 2016
910
New York
Don't really see the point in doing this Justin. Increasing pressure is not the same as increasing volume of flow, therefor you're not increasing the oil flow through the cooler so you're not lowering operating temperatures. If anything you would technically be increasing temperature. The lower cruise/idle pressures are more than adequate and the high load/rpm pressures are already very very high from the factory.

This was not done to decrease oil temps. Nor did I say increasing pressure decreases oil temps. This was done to save/increase bearing life.

When you have well known engine builders on the platform stating they have several engines coming in with wiped bearing surfaces you start to look at things like this.

Please re-read the original post.
 

bahn

Corporal
Nov 5, 2016
111
Davenport, IA
This was not done to decrease oil temps. This was done to save/increase bearing life.

When you have well known engine builders on the platform stating they have several engines coming in with wiped bearing surfaces you start to look at things like this.
Just to be clear, I'm not attacking you or anything. I don't doubt there's motors showing up with shot bearings but the stock oil pressures are plentiful even by race engine "standards". The issue is almost certainly the very tight oil clearances.
 

Twisted Tuning

Lieutenant
Platinum Vendor
Oct 25, 2016
910
New York
Just to be clear, I'm not attacking you or anything. I don't doubt there's motors showing up with shot bearings but the stock oil pressures are plentiful even by race engine "standards". The issue is almost certainly the very tight oil clearances.
Trust me. When I was first approached about it. The first thing I said was the oil pressures are already pretty high as is.

And mentioned that it's possible that it's fuel/oil dilution the culprit
 

bahn

Corporal
Nov 5, 2016
111
Davenport, IA
Trust me. When I was first approached about it. The first thing I said was the oil pressures are already pretty high as is.

And mentioned that it's possible that it's fuel/oil dilution the culprit
Yeah, the stock oil pressures are super high already. BMW probably chose the tight bearing clearance to actually reduce the oil pressure in idle/cruise situations to pickup efficiency. A tight bearing clearance and a quality light weight racing oil can support very high power levels (look at Nascar for instance) but the journals need to be perfect. With tight bearing clearances you need accurate/consistent machining, great oil filtration (particle smears are much more common at lower oil clearances) and a very good oil cooling setup. This is where I feel the problems are coming from as BMW doesn't have the best history with journal consistency (see the S54, S65, S85) or oil cooling. Any N55 engine builders here that have mic'd a handful of cranks, mains and rods?
 

Sbrach

Corporal
Platinum Vendor
Oct 2, 2017
224
When I first started tuning my car I looked at the oil pressure tables, ran some logs, saw 40+ psi at idle and 80+psi at full load and figured I'd leave well enough alone. Interested to see what your testing reveals. Keep up the good work.
 

[email protected]

Corporal
Platinum Vendor
Oct 25, 2016
149
Houston, Texas
Journal consistency isn't the issue. They look fantastic. If you wanted to really pin down the S65 and S85- that's incorrect rod side clearance (too tight of a clearance- We've seen like .06-.08 and it needs to be closer to .18!) is what normally smokes those bearings.

Investigating what we can do to increase additional oil to the cylinder head to help keep the intake camshaft and connecting rod bearings is what should be looked into more. We've poked around with some ideas.
We have an alarmingly high amount of N55's recently that we know of that has smoked the intake cam journals (effectively killing the cylinder head), and connecting rod bearings being wiped out more often than N54's that don't have this technology (not saying that N54's don't share their problems with rod bearings)

The main reasons we see any bearing failure on NG6 engines:

Incorrect oil (but it's synthetic! That doesn't matter. LL01/LL04/LL14Fe+, etc is what matters)
Crappy filters (I can't tell you how many collapsed Korean/Chinese filters we see)
Incorrect oil length service intervals (6 months/7500 miles in our opinion is about the max we like to see stock engines go)
Driving the car too hard on cold oil (160* minimum!!!)
Asking a high mileage car to make a bunch of power past stock.

There is a SIB from BMW on oil repairs, regarding priming the engine before starting it. Beleive me, BMW knows theres an issue with the NG6 engine wiping bearings after repairs, We've seen it first hand, and also had to deal with it as well.
 

bahn

Corporal
Nov 5, 2016
111
Davenport, IA
Journal consistency isn't the issue. They look fantastic. If you wanted to really pin down the S65 and S85- that's incorrect rod side clearance (too tight of a clearance- We've seen like .06-.08 and it needs to be closer to .18!) is what normally smokes those bearings.

Investigating what we can do to increase additional oil to the cylinder head to help keep the intake camshaft and connecting rod bearings is what should be looked into more. We've poked around with some ideas.
We have an alarmingly high amount of N55's recently that we know of that has smoked the intake cam journals (effectively killing the cylinder head), and connecting rod bearings being wiped out more often than N54's that don't have this technology (not saying that N54's don't share their problems with rod bearings)

The main reasons we see any bearing failure on NG6 engines:

Incorrect oil (but it's synthetic! That doesn't matter. LL01/LL04/LL14Fe+, etc is what matters)
Crappy filters (I can't tell you how many collapsed Korean/Chinese filters we see)
Incorrect oil length service intervals (6 months/7500 miles in our opinion is about the max we like to see stock engines go)
Driving the car too hard on cold oil (160* minimum!!!)
Asking a high mileage car to make a bunch of power past stock.

There is a SIB from BMW on oil repairs, regarding priming the engine before starting it. Beleive me, BMW knows theres an issue with the NG6 engine wiping bearings after repairs, We've seen it first hand, and also had to deal with it as well.
Interesting, thank you for the information Alex. So based on what you've seen you're thinking the volume of oil flow to the head isn't sufficient? Keep us updated on what you find in regards to the rod bearings as well.
 

[email protected]

Corporal
Platinum Vendor
Oct 25, 2016
149
Houston, Texas
In my opinion, no. For the most part we've identified what kills rods bearings already- The client :D
Lack of maintenance, taking an oil service for granted, going too long, using bad stuff and sluffing off a professional shop and going to a quick lube place is what kills these things.
To add further insult to injury, the priming SIB is a telltale sign that BMW knows they have an oiling issue as well.
 
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Reactions: Rob09msport

bahn

Corporal
Nov 5, 2016
111
Davenport, IA
In my opinion, no. For the most part we've identified what kills rods bearings already- The client :D
Lack of maintenance, taking an oil service for granted, going too long, using bad stuff and sluffing off a professional shop and going to a quick lube place is what kills these things.
To add further insult to injury, the priming SIB is a telltale sign that BMW knows they have an oiling issue as well.
Haha, sounds "good" :)
 

cookiesowns

Lurker
Nov 13, 2017
24
There is a SIB from BMW on oil repairs, regarding priming the engine before starting it. Beleive me, BMW knows theres an issue with the NG6 engine wiping bearings after repairs, We've seen it first hand, and also had to deal with it as well.
Can you by any chance share the SIB from BMW? My TIS sub just expired, and don't have a need to renew yet. ( Hope it's not something like remove all coil packs, or disable fuel injectors )

Curious, since the M2 from factory has "GTS" cold start, and I generally let the oil drip for awhile when doing changes.

Do you feel Motul 8100 5W-40 is too thick for an otherwise stock car?
 

Twisted Tuning

Lieutenant
Platinum Vendor
Oct 25, 2016
910
New York
In my opinion, no. For the most part we've identified what kills rods bearings already- The client :D
Lack of maintenance, taking an oil service for granted, going too long, using bad stuff and sluffing off a professional shop and going to a quick lube place is what kills these things.
To add further insult to injury, the priming SIB is a telltale sign that BMW knows they have an oiling issue as well.

Only car I ever took to a quick lube is my $1200 beater, lol. Because I was too lazy to do it myself. And its pretty much a throw away car when/if something happens to it.

don't forget that more often than not, OEM's make hose procedure bulletins and etc. simply to cover their ass in the case of a Warranty claim.
 

Bnks334

Sergeant
Dec 1, 2016
402
New York
Just to be clear, I'm not attacking you or anything. I don't doubt there's motors showing up with shot bearings but the stock oil pressures are plentiful even by race engine "standards". The issue is almost certainly the very tight oil clearances.
I think tight bearing tolerances are exactly why you might want to target a slightly higher oil pressure than stock when tuning for higher load. Higher pressure ensures that there is oil for the bearings to draw in as you increase the rate of acceleration. BMW saw the need for the high oil pressures and a high rate of flow. Can't hurt to run to oil pressure 5psi higher when tuning for 2x the engine power of a stock car lol

I think oil thickness and waiting for the car to "warm up" could definitely be a big issue. Even with a 0wt oil I remember seeing 130psi+ oil pressure on cold starts this past winter. Oil pressure takes a few minutes to normalize and it's not until then that flow is adequate to drive the car hard. Now consider people have tuned for 2x power. Flow definitely won't be adequate at high loads until oil pressure stabilizes... Basically, a lot of it is probably user error.
 
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Twisted Tuning

Lieutenant
Platinum Vendor
Oct 25, 2016
910
New York
Oil pan designs have always attributed to oiling issues on most production cars when tracking them.

I mean, realistically speaking, these cars werent designed for extended track duty. So the failures dont surprise me one bit.

Having a track car is more than just tires and power.

Everything on the vehicle needs to be addressed.

Not forgetting the fact that some failures come from people trying to run 20 minute sessions on a tune meant for all out 10-15 second spurts
 

Bnks334

Sergeant
Dec 1, 2016
402
New York
I moved my post about the oil pan to a dedicated thread.

Looking forward to TwistedTuning getting me set up with some oil pressure adjustments on the new engine. Glad I asked for the logging pids way back because it looks like it's something I'm going to have to keep a better eye on.
 
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