Addressing N5x oiling and spun rod bearings (Accusump installed)

  • Login or Register, members don't see Ads!
  • Tip: You can toggle the Dark Theme at the bottom of the page

Bnks334

Sergeant
Dec 1, 2016
388
New York
Thx! Sorry for not being clear, for brand I was referring to AN hose, since the cheap stuff you bought broke.
Not sure man i guess it's all Chinese crap at the end of the day. Buy from Summit Racing or something like that though so you at least know they are selling a decent product. I ended up at my local race shop and paid some ridiculous amount like $50 for hose lol. Needed it quick to get back up and running. Looked like cheap crap too.
 
  • 1Like
Reactions: AndyW

Bnks334

Sergeant
Dec 1, 2016
388
New York
Here:

View attachment 29315

While discussing with Andy earlier today it hit me that my system might be weak on left turns because the outlet sits on the left side of the oil pan. Will try to take some more pictures later this week.
This might be why your oil pressure is reading so high. I don't think you can take oil pressure from the oil cooler feed line. I think excess pressure is bypassed by the oil pump relief valve after the oil goes through the oil filter and oil cooler. There is a bypass valve which can bypass the filter and the oil cooler in the event of a clog, but, I think that only plays into things at 120psi+.

I think to get a better view of actual oil pressure you need to t-off from the stock oil pressure sensor location which is the LAST thing in the line before oil gets fed into the block. Or, T into the oil temperature sensor which is mounted off the main oil galley on the side of the block down near the starter/dme.

it would be interesting to have a sensor at both locations to see how they correlate lol
 

Asbjorn

Sergeant
Mar 10, 2018
455
Europe, based in China
This might be why your oil pressure is reading so high. I don't think you can take oil pressure from the oil cooler feed line. I think excess pressure is bypassed by the oil pump relief valve after the oil goes through the oil filter and oil cooler. There is a bypass valve which can bypass the filter and the oil cooler in the event of a clog, but, I think that only plays into things at 120psi+.

I think to get a better view of actual oil pressure you need to t-off from the stock oil pressure sensor location which is the LAST thing in the line before oil gets fed into the block. Or, T into the oil temperature sensor which is mounted off the main oil galley on the side of the block down near the starter/dme.

it would be interesting to have a sensor at both locations to see how they correlate lol
So my oil pressure is accurate below whatever the relief valve is set to, meaning that idle readings are accurate, and pressure drops due to lateral G-forces are accurate, right? So the results in relation to the functionality of the semi-dry oil system, and how it doesn't work well on left turns with slicks, are still valid?
 

Bnks334

Sergeant
Dec 1, 2016
388
New York
So my oil pressure is accurate below whatever the relief valve is set to, meaning that idle readings are accurate, and pressure drops due to lateral G-forces are accurate, right? So the results in relation to the functionality of the semi-dry oil system, and how it doesn't work well on left turns with slicks, are still valid?
I am not really sure to be honest. It's the 100psi+ that prompted me to question the sensors location.
 

Bnks334

Sergeant
Dec 1, 2016
388
New York
Just for reference, the BMW inline six hasn't changed much over the years. The oil pan itself hasn't changed much either but something else has...

BMW E36 oil pan:
29336


BMW E46 oil pan (pretty much very similar to what I did with my oil pan when I had it out...):
29337


And finally the N5x oil pan:
29338


@Asbjorn notice how the E46 kept a small baffle on the "shallow" end of the pan? Probably specifically to address oil movement during left-hand turns... I guess my MS paint picture from my OP could be pretty accurate lol.
 
Last edited:
  • 1Informative
  • 1Like
Reactions: AndyW and Asbjorn

AndyW

Lurker
Jul 17, 2019
10
FYI, I was at a car race Saturday. At least 4 of the PRO3 cars(E30s) had Accusumps. I think I am sold on that option. As you said, the basic BMW 6 cyl engine is essentially the same on the bottom over the past 30 yrs.
 

Bnks334

Sergeant
Dec 1, 2016
388
New York
Bnks334, What model number is that Accusump? 24-016? Thx.
24-006 3 Quart Accusump
24-200 Accusump Brackets
24-275X 55-60 PSI E.P.C. Pro Electric Valve Kit

I didn't know there was a "high pressure" version until you just shared that part number. Mine works fine. You can call and ask what the difference is.
 
  • 2Like
Reactions: JPuehl and AndyW

AndyW

Lurker
Jul 17, 2019
10
24-006 3 Quart Accusump
24-200 Accusump Brackets
24-275X 55-60 PSI E.P.C. Pro Electric Valve Kit

I didn't know there was a "high pressure" version until you just shared that part number. Mine works fine. You can call and ask what the difference is.
Interesting...wierd how the 006 is 16" long and the 016 is 22" long and both are 4.25" diameter...yet have the same capacity? Physics would say otherwise.
 

Asbjorn

Sergeant
Mar 10, 2018
455
Europe, based in China
Just for reference, the BMW inline six hasn't changed much over the years. The oil pan itself hasn't changed much either but something else has...

BMW E36 oil pan:
View attachment 29336

BMW E46 oil pan (pretty much very similar to what I did with my oil pan when I had it out...):
View attachment 29337

And finally the N5x oil pan:
View attachment 29338

@Asbjorn notice how the E46 kept a small baffle on the "shallow" end of the pan? Probably specifically to address oil movement during left-hand turns... I guess my MS paint picture from my OP could be pretty accurate lol.
Ihave asked my local shop for a quote on doing something similar to the small baffle. This might do the trick.
 

AndyW

Lurker
Jul 17, 2019
10
Canton's reply, "High pressure is for systems that make over 100 PSI. The longer Accusump allows the piston to travel further down the bore than the shorter Accusump. This in turn allows the Accusump to dump more efficiently in a high pressure system."

Gonna get the smaller one.
 

AndyW

Lurker
Jul 17, 2019
10
So, being kind of a nerd, I did some statistical analysis to determine which pressure setpoint kit I should get. Here is the data:

On a track day last year I logged last year, here are some relevant stats(for clarity I removed the "tails" from the data by not including anything at the beginning or end that was less than 20 mph to exclude staging and returning to the paddock):

MAX
92.16​
MIN
42.15​
Median
71.08​
Average
68.50​
Percentage of time less that 60 psi
28.94%​
Percentage of time less than 45 psi (there were none less than 40 psi in the reduced dataset)
0.49%​
Longest duration period less than 45 psi
1 sec​

This would indicate that, for safety only, the 35-40 psi setpoint would clearly be adequate, however, to ensure a consistent pressure close to median or average is maintained, the 55-60 psi setpoint is better suited.

One of my concerns is that, if I pick the 55-60 setpoint, it is one more thing I have to manage(remember to turn it on right as I get on the track, remember to turn it off at the end, remember to turn it off on the track if there is a flag that requires me to slow down, etc). I am not sure of the consequences of accidentally adding 3 quarts of oil to the engine so maybe I am being overly conservative. @Bnks334 , have you had any issues with this?

If I go with a 35-40 psi kit, I can probably step down to a 2 quart model given the small percentage of time it may actuate and save some weight/space in the engine bay. Going to mull on this a bit after I take a newer set of data next Wednesday.
 

Bnks334

Sergeant
Dec 1, 2016
388
New York
So, being kind of a nerd, I did some statistical analysis to determine which pressure setpoint kit I should get. Here is the data:

On a track day last year I logged last year, here are some relevant stats(for clarity I removed the "tails" from the data by not including anything at the beginning or end that was less than 20 mph to exclude staging and returning to the paddock):

MAX
92.16​
MIN
42.15​
Median
71.08​
Average
68.50​
Percentage of time less that 60 psi
28.94%​
Percentage of time less than 45 psi (there were none less than 40 psi in the reduced dataset)
0.49%​
Longest duration period less than 45 psi
1 sec​

This would indicate that, for safety only, the 35-40 psi setpoint would clearly be adequate, however, to ensure a consistent pressure close to median or average is maintained, the 55-60 psi setpoint is better suited.

One of my concerns is that, if I pick the 55-60 setpoint, it is one more thing I have to manage(remember to turn it on right as I get on the track, remember to turn it off at the end, remember to turn it off on the track if there is a flag that requires me to slow down, etc). I am not sure of the consequences of accidentally adding 3 quarts of oil to the engine so maybe I am being overly conservative. @Bnks334 , have you had any issues with this?

If I go with a 35-40 psi kit, I can probably step down to a 2 quart model given the small percentage of time it may actuate and save some weight/space in the engine bay. Going to mull on this a bit after I take a newer set of data next Wednesday.
Since I wired up a light and a switch it has been fine. I see the red light blinking and it's a quick reminder to flip the switch off as I roll into the pits. It's really just as simply as flipping the switch on upon entering the track and then back off on the way back into the pits. It's ok for the Accusump to dump and refill throughout a roadcourse event. The issue is when you sit at idle at 40psi with the electronic pressure solenoid constantly firing. It will burn out quickly from constantly opening like cranking a car for 30seconds + will burn out the starter.

I am surprised to see you spend 29% of the time at <60psi. I only drop below 60psi at <3000rpm and I usually downshift before rpms dip that low to take advantage of engine braking.
 
Last edited:

AndyW

Lurker
Jul 17, 2019
10
Since I wired up a light and a switch it has been fine. I see the red light blinking and it's a quick reminder to flip the switch off as I roll into the pits. It's really just as simply as flipping the switch on upon entering the track and then back off on the way back into the pits. It's ok for the Accusump to dump and refill throughout a roadcourse event. The issue is when you sit at idle at 40psi with the electronic pressure solenoid constantly firing. It will burn out quickly from constantly opening.

I am surprised to see you spend 29% of the time at <60psi. I only drop below 60psi at <3000rpm and I usually downshift before rpms dip that low to take advantage of engine braking.
My car is a DCT, so no engine braking. This dataset was also with the car in auto. I just did a quick conditional formatting of RPM and oil pressure with color on the dataset and visually compared and the <60 psi is definitely associated primarily with less than 3K. (percentage of time <3K was 34%).

I gotta figure out where to put that light and switch. I try to keep this car as "stealth" as possible on this kind of stuff.
 

Asbjorn

Sergeant
Mar 10, 2018
455
Europe, based in China
Ihave asked my local shop for a quote on doing something similar to the small baffle. This might do the trick.
Here's the new oil pan baffle that my shop made, complete with one-way door to the pick up area. The red circles are were the small oil cooler and aux pump is connected.

Can't wait to test it out on track.

574496702.jpg


Here's the old "baffle" I ran before. It had an opening at the lowest point, but no one-way door.

911354409.jpg
 
  • 1Love
Reactions: derekgates

Create an account or login to comment

You must be a member in order to leave a comment

Create account

Create an account on our community. It's easy!

Log in

Already have an account? Log in here.

Top