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  • hubcapboy
    replied
    Ugh I hope we aren't losing photos. I had to go back and re-post like 10 a few weeks ago.

    I certainly hadn't considered any n52 headers, because I hadn't understood how the O2 sensor relocation worked. Your response a few pages back that you just add a delay for the header tune probably means that it's worth investigating that. I have no intention of running cats. I expect this engine is cleaner without a cat than the M20 was from the factory... certainly than my m20 is right now with the cat rattling around.

    Cheap ebay M20 headers are $100, cheap ebay n52 headers are $500 (shipped). That's too pricey for something that I already have a solution for. If anyone has a banged up set or knows one of the manufacturers and they want to know if they fit the chassis (with the engine mounted here) I'm happy to test fit them.

    I think my reach goal would be a cut-down cluster with just the e46 or e90 or e85 cluster display. I'll worry about that later, but it would be fun to have that mounted somewhere other than the cluster.

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  • nando
    replied
    Interesting - but I dunno, I feel like that would be so out of place in an E30. I'd probably run my E46 M3 cluster before that. I think it wouldn't work without all of the other modules, either.

    regarding your alignment pictures - the first one in the above post isn't working.

    As far as the mount/header clearance. Have you considered picking up a set of cheap ebay headers to see if they will clear? Unless you're in california, I can't imagine anyone running the stock E90 cats. If you want cats, I'd run one in the E30's original location.

    Leave a comment:


  • hubcapboy
    replied
    Um. Guys.

    https://www.youtube.com/watch?v=9r7j2b94K14

    Leave a comment:


  • hubcapboy
    replied
    Someone PM'd me with a fear about exhaust manifold clearance. There's a huge weird schwoop shape in the factory starboard side engine arm that I didn't re-create. It's to clear these cats:
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    If you aren't running the cats, there's a ton of room to turn a little higher and clear the fabricated arm:

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    The arm ends up just aft of the gap between the manifolds.

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  • hubcapboy
    replied
    It ended up here...




    Not even close to the middle of the diff. Not *exactly* 5/8"... about another 1/4" to the port side (right in this photo). But damn close to the centerline of the car according to our diff output flange measurement.

    So what. Is going. on. Maybe everyone else on this forum already knows this. I couldn't figure out what was going on. I went back out in the dark just now to try and figure out what was centered and what wasn't. The pictures aren't great, but I have two long aluminum straight edges that I think are for drywall. One has a pinned 90 degree tee. There's a rib that looks like it must be perpendicular to centerline right where the fuel lines turn, and I could measure the inside-to-inside between the pinch welds at the sills along this ridge. The straight edge is held against it on the left here:

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    I took the centerline of the car and set my 90 deg square against the edge above, and again this is hard to see:

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    I know this is a terrible photo, and the shadow makes it worse, but the visible edge of the tee is dead center on the ovoid in the crossmember, but the diff is offset to starboard (left in the photo). The opening in the subframe is centered, and the pinion yoke is very obviously offset:

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    This is an old photo of the E30 drive shaft (left) and Z4 drive shaft (right):

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    I haven't been able to figure out to this point why a driveshaft from a motor and transmission mounted to the frame, to a CSB mounted to the frame, to a diff mounted to the frame, needs U joints.... and if they do need u Joints, why doesn't the front section need u joints between where the trans output is to the CSB? The engine is the big heavy moving thing at the front, and it seems like the lever arm with the hard point at the CSB would just reef on it every time it moved.

    The reason for the U joints is that from the CSB to the diff, there's a horizontal offset. The diff pinion and crank are parallel, but not concentric. The U joints are there in the back half of the shaft to allow the shaft to deviate to one side (something around 5/8") so the diff can be centered. The E30 joint arrangement is notoriously difficult to align because one of the joints is in front of the CSB. I'll be using the Z4 assembly order, but with the correct E30 CSB carrier (not flipped... in the correct location). If I can't get this aligned at the transmission output with shims, I'll modify it. I'll check to make sure that the pinion yoke and trans output are parallel (and adjust that with the transmission mount) so that the u joints have equal angles.

    Leave a comment:


  • hubcapboy
    replied
    Ok. hoveringuy and I spent about two hours shouting at each other through masks in my driveway this morning about drivelines, engine position, and wiring. I learned a ton. I went back out just now to confirm some things in the dark. Best time to make these kind of observations.

    First of all, the driveline is not centered down the car. It's more complicated than that. Since we were looking at a car with a missing motor (or at least not a factory motor) we started from the diff. I pulled my spare out from the back of the garage and we were already slapping our foreheads:

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    The pinion yoke is NOT centered between the output flanges of the diff. The casting is very obviously not symmetrical (I would have put money on this from memory if you'd asked me). The yoke is very, very obviously off to the starboard side of the diff... just look at the relationship between the front two diff mount bolts and the input. The output shafts are the same part number, and there's no difference in the hub thickness between left and right... The diff output flanges are centered on the car, and the input is off to one side. How much?

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    Something metric, but it's about 5/8".

    I centered the engine using the 330i engine arms against the frame rails, and checked it against the ball joints. The centerline of the engine is correct. I centered the shifter in the tunnel opening, and had the shift carrier in the bushing when I locked down the engine position, so rotation in the vertical axis was correct. the lean angle of the engine was checked against a few parts of the car that looked "level" and I'm within a 10th of a degree. Engine and transmission height were guessed... for sure... but that doesn't mater for now. The question is... is the engine pointed at the diff, and if not, why not. We looked at the complete engine/trans and convinced ourselves that the input and output of the transmission were probably aligned (the output is at least aligned with the casting joint, which looks as much like the CL of the trans as it can be.) So crank center can stand in for trans output center. We centered a stringline at the front main seal:

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    And then one of us pulled it tight against the rear subframe while the other shouted directions until it was centered in the rear main seal:

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    Guess where it ended up?


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  • hubcapboy
    replied
    Lol. It’s a lot of the reason I don’t already have a driveshaft built. I wasn’t willing to get under my silver car to find out if it’s the early or late center support bearing. I suspect that the red car I’m working on is late (88), and my silver car is early 87) but I’m not planning on driving the red car around so I’ll figure it out when the time comes.

    Leave a comment:


  • nando
    replied
    Hmm. The Ix doesn't have a csb. Not sure what that means honestly.

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  • hubcapboy
    replied
    I would think the same thing, but the CSB is offset... So the car isn’t symmetrical...

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    Attached Files

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  • nando
    replied
    I'm pretty sure it's centered. It's not like BMW (in the past anyway) to do something so ugly. I'd have to dig out my G260 to check for sure, but based on the transfercase alone, I feel pretty confident it isn't offset from the crank centerline.

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  • hubcapboy
    replied
    The only reason I didn’t go that far when I was bore-sighting is I’ve heard a rumor that there’s an offset between the crank and the output from the transmission. So the CSB may not actually be concentric with the crank...

    Leave a comment:


  • LukeJ
    replied
    You could run a string down the bores in the 3 or 9 o'clock position. Tape it to the front and get it to where it just touches the back bore.

    Run the string out to the CSB and see if there is a noticeable angle. Like a horizontal plumb bob.

    Leave a comment:


  • hubcapboy
    replied
    No, you’re helping. Trust me.

    can someone weigh in with whether the crank is truly on the centerline? I guess even if it’s offset, it should be straight.

    tomorrow I’ll make a plug for the front and rear main seal with a center to measure to, and I’ll get a distance to the frame rails on each side.

    do we know that the frame rails are symmetrical over the centerline?

    Leave a comment:


  • LukeJ
    replied
    This is what I see when I look at this picture. Click image for larger version

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  • LukeJ
    replied
    As far as measurement goes.

    Are you able to measure from the back of the block to the subframe on both sides?

    I'd think having the block square to the subframe would be better than square to the radiator.

    I realize I've got no 'street cred' here. I just showed up yesterday and put myself in the conversation.

    I have been lurking for the last year or so, whatever that's worth.

    Mostly though, I have 20 years of precision measurement and machining under my belt. So that's where I'm 'coming from' in my comments.

    Leave a comment:

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