I have the whole winter to think about what to do with it, thankfully it is not my only car. I would definitely seek a running used motor to refresh. What I hate the most is that I have no idea what might've caused it between general oil starvation, running it on fumes to a hard misfire at WGI in July, pressure drop/debris from the dual 25s I've literally JUST installed, debris from the assembling fittings, pushing the car on low oil while populating the coolers, or hard rev limiter. FWIW yesterday I hit limp mode after a pull, with an exhaust vanos code. Doesn't really narrow down much and really destroys an confidence I have working on cars
I have the whole winter to think about what to do with it, thankfully it is not my only car. I would definitely seek a running used motor to refresh. What I hate the most is that I have no idea what might've caused it between general oil starvation, running it on fumes to a hard misfire at WGI in July, pressure drop/debris from the dual 25s I've literally JUST installed, debris from the assembling fittings, pushing the car on low oil while populating the coolers, or hard rev limiter. FWIW yesterday I hit limp mode after a pull, with an exhaust vanos code. Doesn't really narrow down much and really destroys an confidence I have working on cars
Any debris in the oil coolers would not have been filtered but I doubt that had anything to do with it.
I have never seen logs of oil pressure with dual oil coolers, but N55 oil pumps have pretty high overhead. Not sure about N54 vs N55 though.
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First thing I'm ordering is a AA oil distribution block and a pressure sender/gauge. Not going in blind on dual coolers again.
N54 can't log oil pressure at all? I thought the sensor on the top of the oil filter housing was the pressure sensor on both engines, no?
That is just the 7 psi pressure switch. I was wondering why n55s can log pressure, technical documents say it's on the pump itself for your car.
Again I'm not sure on how n54 oiling works. I guess pump output is completely fixed which means pressure drop could be a concern.
N55 oil pressure sensor is where the n54 "pressure switch" is. Right on the oil filter housing. Thats what the n55 engine PDF says anyway. There is an electrical chart there as well which shows the pressure sensor on the oil filter housing. The sensor is similar to n54 but more expensive and listed as a pressure sensor instead of a switch...
Edit:
Looks like you're right that the N54 only got a switch. Oil pressure yes/no. So much for "ultimate driving machine." Tee into that switcb port or just remove it all together and plug in an n55 sensor lol. N54 doesn't even seem to care if that oil switch gets unplugged, according to some of the posts I've seen.
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I looked it up again, you're right about the location, but I remember so vividly seeing something saying otherwise. It appears to be on/off in the signal it sends. I monitored several oil related parameters the night I drove the car around after adding the coolers, including oil pressure switch which I'm pretty sure was measured in mg/stroke with a constant value of 1. MHD actually added oil pressure parameter a while ago for the N54 but reads zero. I would love to see oil pressure read in the DME
I actually have one I can send you. It should be plug and play, mechanically. You would need to speak with someone like jake y to get the DME to interpret the 5v signal to a psi value. He posted some things on N54 tech suggesting he is knowledgeable and might've already done something similar.
At the very least, you should be able to tap a mechanical/digital gauge into it to display oil pressure.
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gotcha, in any case I can use AA's tee for the stock pressure switch port.
Starting to think that perhaps WGI hammered in the final coffin nails with its banked high g sustained sweepers. We both know NJMP's G load is pretty low, save for turn 9 tbolt and the final bowl on lightning, but neither compare to turn five and six at Watkins. Downhill, cambered, and sustained for what seems like an eternity sometimes. I feel significant flex in my fixed back recaros on that track.
B58 engine PDF goes into much more detail of the map control oil pump strategy used in the n55+ engines. There is indeed 2 separate oil control methods. Normal map controlled and emergency. It also describes the oil pressure relief valve post oil filter which only comes into play at a range of 11.4 bar (+/- 1.4bar). Not exactly the same system because of the oil filter housing changes but the pump and strategy is the same.
There is also quiet a it of interesting info in there from BMW regarding con rod bearings. BMW seems to be targeting cold start wear and tear as a source of bearing wear. They have coated the upper shells of the B58 rod bearings with IROX to prevent wear due to tight tolerances and reduced cold start oil film thickness.
https://www.1erforum.de/attachments/bmw_b58_engine-pdf.84135/
There is also quiet a it of interesting info in there from BMW regarding con rod bearings. BMW seems to be targeting cold start wear and tear as a source of bearing wear. They have coated the upper shells of the B58 rod bearings with IROX to prevent wear due to tight tolerances and reduced cold start oil film thickness.
https://www.1erforum.de/attachments/bmw_b58_engine-pdf.84135/
I am not entirely sure how the 2nd pump is powered or how it attaches to the block. Someone already did this swap. They should be able to help with what exact "modifications" the parts need. I am guessing at least $1500 though between the pump and the baffled pan... Not to many M2/3/4 cars to pick these parts off of.
krisa9977 on 2addicts
https://www.2addicts.com/forums/showthread.php?p=22996564
I just finished reading through his thread before checking if you had replied lol, seems to have a driveshaft that connects both pumps together? I think any decent baffle plus the accumulator gets you at least half way there price wise. I would just buy all new parts except for the pan if I can find it at a junkyard.
Would this work on a 2011 N55 or does it have to be the newer F series?
I can't confirm that. It's all the same part numbers use don the M235iR N55, but that guy said some slight modifications were done to the parts. It's obviously doable and he had no issues he says.
I like that the Accusump increases your oil capacity and it can continue to inject oil even if starvation occurs. There is still the chance that oil drain-back is an issue with high rpm for extended periods of time. The Accusump also allows me to prime the engine with oil prior to cranking. This is something I really like for cold starts. I just need to be quick with starting the car before the DME window throws the oil pump into emergency mode. Seems to be around 3seconds.
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I just want to update that the e-series n55 wont be able to use the m2 oil pan without some fabrication work. The m2 uses an electric power steering rack whereas on the e series n55 is a hydraulic pump which is partly mounted to the oil pan. The m2 oil pan does not have the provisions for the power steering pump. F-series n55s are also electronic steering so they wont hit this snag.
Update:
Here is some autocross comparison data:
https://datazap.me/u/banks334/autocross-accusump
There are 3 logs there, the first log is with the Accusump, the second log is without the Accusump, and the third log is of oil pressure on decel in order to be able to compare actual oil pressure during the runs to what oil pressure is supposed to be.
You can see that oil pressure is dipping down to ~40psi during several turns and rpm is still above 3,000rpms which means oil pressure should be over 60psi. This could potentially indicate that the pick-up is grabbing some air. With the Accusump (60psi electronic valve), oil pressure is above 60psi across the run except in two places toward the end. Oil pressure dips in two places down to about 48psi. The short bursts of acceleration in an autocross probably limits how well the Accusump can re-fill. The results are still much better than the run without the Accusump.
Here is some autocross comparison data:
https://datazap.me/u/banks334/autocross-accusump
There are 3 logs there, the first log is with the Accusump, the second log is without the Accusump, and the third log is of oil pressure on decel in order to be able to compare actual oil pressure during the runs to what oil pressure is supposed to be.
You can see that oil pressure is dipping down to ~40psi during several turns and rpm is still above 3,000rpms which means oil pressure should be over 60psi. This could potentially indicate that the pick-up is grabbing some air. With the Accusump (60psi electronic valve), oil pressure is above 60psi across the run except in two places toward the end. Oil pressure dips in two places down to about 48psi. The short bursts of acceleration in an autocross probably limits how well the Accusump can re-fill. The results are still much better than the run without the Accusump.
