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(under construction) Chopping E34 strut housing

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    (under construction) Chopping E34 strut housing

    ** Im gonna update this thread as i go so bear with me**

    Getting Ready


    Alright, so i recently installed JOM coilovers to my touring, the front was half an inch taller than i would like it to be, even with the adjuster all the way to the bottom. I wanted to be where im at now but at the top of my adjuster. Id also like to have more suspension travel at this height(and lower)So i decided to shorten my strut housings. I couldnt find a thread on how to do this in a e34, but using thread for e21 and e30, i felt comfortable enough to give it a try, but the problem was i didn't know what strut to use.
    After a long day of looking at catalogs trying to find a strut that was exactly the same except 3-2in shorter. the struts I took out of the housings ( my JOM ones) where Three different size diameter, slightly tapering down, the smallest section being ~46ish mm and the largest being ~49mm. i contacted KYB and they informed me that the largest diameter of cartridges they make is 46mm, which they said is the diameter of they're e34 ones. i asked them to try to find me a strut that was the same diameter but around 15-14 inches in tube length(stock e34 being ~17.625") they responded with part number 366006 which is out of a bunch if early 90s Audis, I ordered two in to measure and compare to the JOM.
    Comparison Photos
    (please note that im comparing the Audi KYB to the JOM strut insert, not a e34 KYB)
    Length of tube


    length of piston is resting

    diameter of strut

    diameter of piston

    length of mounting section

    **see below on how this will still work**
    As you can see, 4in drop is way to much, so to correct this I found that old Aircooled VW axle spacers and the same diameter as the strut and are a little over a 1/2 inch, so adding two to the bottom of the housing before I install will make up for that


    the exact measurements are as followed
    the stock strut tube length-447.675mm (17 5/8in)
    the Audi strut tube lenth-350.8375mm (13 13/16in)
    spacer size-15.43mm(3/5 inch)
    total length to be cut out(using two spacers)-
    65.9775mm
    or
    2.59753937in removed,
    but to make sure the new strut doesn't rattle around when the top is fully tightened, we will be cutting it at 2.8inch, so the housing will be a little more shorter than it needs to be and new strut slightly sticks out and it will tighten down fully(controlled error) and put more pressure on the strut inside the housing removing any wiggle room for rattling.
    also to remove a bit of the diameter issue use a BMW sensor oring (part number below) around the thin section of the audi strut.

    the thickest part of the JOM strut(which is very snug) is 49.58

    the o-ring on the thin part of the strut puts the diameter of 50.97mm

    below i will show how i installed it.

    Parts List
    -2x KYB 366006
    -4x Empi axle spacers 2252817
    -2x e30 style strut mounts 31 33 1 139 452
    -2x bearing dust shield 31 33 1 110 196
    -2x mount caps 31 31 1 139 453
    -2x washers 33 31 1 125 916
    -2x washers 31 33 6 776 760
    -2x e90 drop hats 31 33 6 764 093
    -2x bmw sensor orings 12 61 1 277 129

    I ended up having to run the e30 style strut mounts ( I believe its what early sedans came with?), the solid one piece that my 92 is supposed to have, the part that goes though the mount is to short
    **see picture of mounting length above**
    but was the exact same length as a early model e34 strut insert.
    (see thread about the changes in mounts over the years of e34 production run)
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    Once all the parts are gather time to tear things apart



    Start Fab Work

    First thing you need to do is disassemble and then the spring perch needs to be removed


    I used a large chop saw, this works but getting the cuts perfect it pretty tricky. using a hand pipe cutter would be alot more precise but it would take longer. making the first cut can be really anywhere aslong as its below the threaded part.




    next I made a template that was the 2.8 inches and marked with a sharpie

    after you mark it make your second and last cut. this piece can be tossed. I kept it around to balanced while i weld resting the housing on it.

    next clean off the section of metal that you will be welding. also you may find that your cuts where not a perfect right angle, smooth it out as flat as possiable and line them up. i used the old strut that fit in there snug as a guide to make sure the where as true as i could get it.

    Next Tac it in place, making sure that after each tac weld that the strut can still be rotated in the housing, getting you weld to hot and getting a bubble of it in the housing wont be good.



    next with the fill in the spots between your tac welds, the strut i used as a holder was blown and all the fluid had been expelled, so i kept it in, rotating it after every weld, DONT WELD WITH A STRUT THAT STILL HAS PRESSURE! the heat can cause it to exploded(worst case) also be careful to to weld to hot and weld the template strut to the housing .

    Using a grinding wheel clean of any slag or just to clean it up a bit
    remove the strut from the tube and check inside to make sure your weld didnt get inside the tube.


    Now put the axle spacers in the tube(make sure its sitting flat) and install the new strut, i ended up only using one of the axle spacers.
    now put the oring down in the tube, using a small flat head to push it down a bit.

    now install the retainnig colar(mine being my adjusters for my coil-overs) tighten down and give the strut a wiggle, it should be very snug and give no movement.
    primer and paint your welds to prevent rust!

    now finish the install of the springs, spring pads, spring hats, big washer, bearing dust cap, strut mount, small washer, and nut.
    the nut that came with my struts was a but to long so it didn't get in to the nylon section of the nut. it need to go in to the section to keep it tight, so go to you local hardware store and find a shorter one or use two thin non locking nut and but them up against each other


    Now reinstall the shortened housings in your car, my wheels ended up hitting the adjusters so i have to order spacers to clear them, but i have but the car back on the ground and its alot more stiff feeling and with my adjusters all the way at the top, the car sits slightly lower than it did when the it was set all the way at the bottom.
    like when doing any work like this on the front end, its a good idea to get an alignment.

    more to come once i get the spacers and after i will give a review on how it rides.
    Last edited by FireFight; 11-24-2015, 09:26 AM.
    WTB:m60b40 in PNW
    Zachary Ripley

    85 318i M50B25tu.
    92 525it 5 speed.
    80 244gl (m60 prepping).


    #2
    updated
    WTB:m60b40 in PNW
    Zachary Ripley

    85 318i M50B25tu.
    92 525it 5 speed.
    80 244gl (m60 prepping).

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