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  • nando
    replied
    I think one of the ideas of having 2 extra quarts is you don't really need an oil cooler.

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  • hoveringuy
    replied
    I don't know how important the actual capacity is. I was concerned about it when Tyler built my pan because he removed about 3" of it. I'm down to about 5 QTS to fill, but I add a 6th to over-fill by a quart.

    I track my car pretty hard. I haven't had oil pressure issues except for hard braking on a on a steep downhill section followed by a sharp right where I'll get occasional flickering oil pressure in the turn. Makes sense, I have a rear sump and the oil is being pinned to the front.

    I've been concerned enough that I run Blackstone oil reports at each change. My latest one just came back and after 6 track sessions where I flogged it hard, the report was the cleanest I've ever had- 8ppm Al, 11ppm iron and 1ppm lead.

    The front sump solves the braking problem, the wider sump would be more susceptible to cornering. I like it!


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  • hubcapboy
    replied
    Seems like I should be able to insert an animated gif...

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    nope. that didn't work. what about this

    Nope. that didn't work either.
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    hopeless. I guess external hosting?



    yea well, who knows how long that image will last but everyone talk it up so people miss out in the future.

    This was some late-night sketching after several hours of poorly mocked up plywood. The engine (all the bmw engines) are tilted back towards the rear of the car. having the steering rack and subframe in the way of sloping the pan down from the rear creates a challenge. I'm pretty sure this accomplishes it while still clearing everything, but I'll start cutting these pieces to check. Oil level is the red line, and capacity at that line is 7L. The depth of the wing is just about right to mount the e30 oil level switch from above, and the bottom of the sump should be just about flush with the bottom of the subframe (my skidplate dips down about 3/4" from there, so should clear this).

    Adding capacity on the low side (starboard) isn't realistic because you still need entry and tool clearance for the pan bolts, so you're only left with a little 2" high wing... and the capacity is already fine.

    significant slope towards the sump doesn't seem to be a priority on any of the factory m20 pans... it's a little alarming to see how little is needed, although there are some ridges to encourage the flow back to the center on the m20 pan:

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    This might just be to reduce sloshing as the oil runs along the pan? Super easy to add once I know my clearance from the n52 windage tray.
    Attached Files
    Last edited by hubcapboy; 08-13-2020, 10:23 AM.

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  • nando
    replied
    There's profiles for multiple batteries - not just the AGM. Most cars don't even have them, they have normal lead acid.

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  • hubcapboy
    replied
    Ugh I love everyone.

    Realizing that not every car with an n52 has IBS is a huge jump I wouldn’t have made by myself. I wouldn’t have thought to check.

    https://www.newtis.info/tisv2/a/en/e...erface/XcGCxRr

    This describes the functions of the alternator BSD on a z4. It’s the same list as on a car with IBS. The DME is connected to battery power... there’s no reason to believe it isn’t aware of battery voltage without the IBS module.

    If a code is stored that the IBS is missing, some of these features might be disabled... but the Z4 flash won’t ever throw that code.

    on top of all this, any advanced charging management the IBS helps with is probably super specific to the factory AGM battery.

    Leave a comment:


  • nando
    replied
    There's a lot of differences. the IBS is complicated enough that I don't fully understand it. I don't think the Z4, for example, uses the IBS. You can enable the IBS using the Z4 calibration, of course, and copy all the settings over. But that doesn't seem like a lot of fun. :p

    Leave a comment:


  • Caperix
    replied
    Not all n52 cars had the ibs. Low option 1 & 3 series have a standard negative battery cable. Nando, you have done the most dme interpreting, have you found if the cars without ibs have any different charge data in the dme? There could always be the option of swapping to an older voltage regulator with the 3 pin connector this is common in e46 as ms45 dme use bsd as well but the older ms43 dme did not.

    Leave a comment:


  • hubcapboy
    replied
    OK. I'll fully stop worrying about it.

    This is the answer to the dash charge light:

    https://www.americanautowire.com/sho...em-test-module

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    There's no reason to try and figure out when or if the alternator's charging if it's being managed and potentially being turned on and off by the DME... the dash light would only indicate that system's operation and not a fault. Repurposing the charge light to notify you when battery voltage drops below 11 volts is WAY more useful.

    Leave a comment:


  • nando
    replied
    Yes, the DME controls them.

    Well, it's more efficient with the IBS sensor - it only charges the battery as needed (reducing drag from the alternator), and theoretically extends the life of the battery by adjusting the charge profile as it ages, and fitting it closer to the actual size of the battery as well (which is why you register the battery size & type on new cars).

    But whether this difference is enough for you to be bothered - I don't know. and certainly, an E30 has much simpler electronics and is much easier on the battery overall than say, a fully loaded X5..

    Leave a comment:


  • hubcapboy
    replied
    Do we know that these alternators are talking and being controlled by the DME?

    I guess my question is unless we know what functions we’re getting out of the BSD... why connect it? Just let the alternator run conventionally?

    Leave a comment:


  • nando
    replied
    Afaik, failsafe just runs it like a regular alternator. Although I don't see why the IBS wouldn't work. But, this has never been a problem.

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  • hubcapboy
    replied
    Work has been... an obstacle. No meaningful oil management progress to report. In the meantime, I’m stressing out about the alternator:

    https://bimmerprofs.com/alternator-management-problems/

    anyone with any insight... I’d appreciate your thoughts. It seems that in cases where the alternator is mismatched with the DME (like, say, if we flash the DME to make it think it’s a Z4) the alternator may refuse to do any of the active management that the serial connection allows. Even if those two components are willing to communicate, the loss of the battery module may cause the DME to tell the alternator to go to failsafe anyway.

    I’m not sure how to reconcile this with the success stories except to wonder if the failsafe is “good enough” for our uses, or if the constant output reduces life of the alternator meaningfully, or if it’s even worth connecting the alternator to the dme.

    I have a feeling this is going to start a hunt for a similar solution to the AC... “is there an alternator that bolts up that just has a voltage regulator.”

    Leave a comment:


  • hubcapboy
    replied
    Maybe the fakes are getting this good, but this looks like a new production japanese made Denso. Their part number for it is 471-1262, and I expected it would pop up in a bunch of different applications based off that number... but it doesn't seem to. I'm sure this is some kind of internal code they use like a 471 pulley is a certain belt width, certain diameter, and the case is a 1262 which is a certain type of pump, certain pattern, and certain output, but I haven't been able to read those tea leaves.

    It's such a low volume part I can't imagine there's fakes tooled up (on the other end of the scale, it's almost impossible to find a real Denso gear reduction starter for a Ford 7.3L diesel...) The packaging is also labelled "no core value" so these may not be rebuildable.

    Leave a comment:


  • nando
    replied
    That's awesome, and makes wiring so simple (just use E30 wiring!). I'll bet you can swap out that pulley too if it's interfering with the radiator.

    I'm sure you already know this, but just make sure you use aluminum bolts instead of the steel ones that probably came with that compressor. Was it remanufactured? it looks brand new.

    Leave a comment:


  • hubcapboy
    replied
    OK... I know I said no more AC updates, but this might be the AC solution... so I might get away with it. I haven't worked on the car for a week because of a trip and work, and now it's raining, but I did get out to pull the tarp off the engine two nights ago and I think this is worth sharing.

    I'm and engineer, but not an electrical engineer. I DO have pretty consistent contact with two pretty savvy practical hardware design electrical engineers both with an interest in this project. We were ready to design a PWM controller for the n52 with off, low, medium, high output settings that pulled a "safe to operate" signal from the e30's AC controls (pressure switches, evaporator temperature, dash buttons, defrost lockout) and then sent a soft-start output signal to the compressor that picked an output from engine RPM (higher RPM requires less output). I have a few PWM controllers lined up on the bench, I pulled out my variable DC power supply... and then this arrived in the mail:

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    The top is the N52 compressor I pulled off (you can see my AC Comp label on the plug I snipped from the harness to start poking at it). The bottom is the compressor from a BMW M73. I didn't know that engine code off the top of my head, so don't be shy if you didn't. It's the V12 from the 7 and 8 series from 1994-2001. In other peoples underhood photos from those cars, it looked suspiciously similar, but as far as I can tell is a conventional clutch operated compressor (confirmed via the 8 series ETM, the fact that the wires go to the front instead of the back, and sheesh it's from 1993). I started this search by looking at serpentine belts. Most BMW compressors are driven off a secondary belt (which is why they're so easy to delete) which has a narrower width and fewer grooves on the pulley. For whatever reason the M73 is driven off the main belt like ours, and had the same number of grooves. They were both Denso OEM, and I figured if they looked this similar there was a decent chance that the bolt faces and pulley location were the same. All of the compressors from this era look like they use a bracket to adapt to the block:

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    Which made me think they were using some Denso standard for the mounting. The N54 has aluminum inserts directly in the mag block that the compressor bolts to. I looked for junkyard compressors to check fit, but as soon as I realized that a new M73 compressor was half the price of a new N52 compressor OR an original e30 compressor, I just bought a new one (and figured if it didn't fit I'd just return it. Here's the back-side of the two compressors:

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    The housings are so similar that I find it hard to believe the internals are different... but... I'm not going to second guess that. I offered the compressor up to the block and it "fooped" right onto the aluminum bosses... exactly the same pattern and diameter. I was so surprised I didn't even measure the pulley diameters. The new one looks a little smaller and might be under-driven at idle, but this is probably helpful for a higher revving engine (ok ok ok... stop PMing me... smaller is overdriven. helpful for... not having to raise the idle when the AC comes on. how 'bout that). There's enough movement in the tensioner to make up the difference if there is one:

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    I better check if it clears my radiator...
    Last edited by hubcapboy; 08-06-2020, 07:29 PM.

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