| wharthog |
Posted
Wednesday, Oct 11th 7:05am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 65
SF Bay,California, USA
1982 323i, , R1150RT |
I have a good friend that owns Bavarian Professionals in Berkeley, CA. Among many other cars he has had a 323i that he imported years ago. I was telling him about all the squeaks and rattles in the rear of my car... he told me to pull the back seat and have a look around because all the sheetmetal (which is obviously structural in our unibody cars) was cracking at the seams. I did and so was mine. Took it to a metal shop and had it all welded up. MY GOD! what a difference!!! If you haven't had your back seat out in a while take a look... this may be common.. |
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| imaradiostar |
Posted
Wednesday, Oct 11th 8:13am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 892
Nashville, TN
81 323i, 82 525i, 85 524td, 90 535i |
yup, I have cracks and rust in that area...currently awaiting the finances to buy the epoxy primer needed to cover everything up when I'm done fixing it.
jamie |
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| MayanArch |
Posted
Wednesday, Oct 11th 2:58pm [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 1175
Florida, USA
Baur E21 2.7 1982, Baur E30 318i 1985, 323i 1978 |
I had not noticed anything. Then again, the Baur does reinforce that area.
Where are you looking, exactly?
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| BarryA |
Posted
Wednesday, Oct 11th 9:59pm [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 175
Sacramento CA
81 320 |
Same issues on my US spec 320i - suspected that was where a lot of the noises toward the rear of the car were coming from. There are multiple cracks all around the rear bulkhead, running in toward the center from the edges - haven't taken the time to strip all the upholstery out of the rear section and get the crackss welded up, but it's on the agenda. Will probably seam-weld the edges at the same time, as well as add some sort of rear shock tower connector. |
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| imaradiostar |
Posted
Thursday, Oct 12th 8:04am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 897
Nashville, TN
81 323i, 82 525i, 85 524td, 90 535i |
I'm leaning toward carefully cutting away the interior layer of the steel and removing all the rust inside as there is quite a bit- looks like a poorly sealed area from the factory. I'll probably have to make or buy a repair panel or cut some portions out of another E21 to fix it. I'm seriously considering a mild re-engineering of the area to reduce the chances of moisture building up while strengthening what seems to be a week spot on our cars.
jamie |
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| wharthog |
Posted
Tuesday, Oct 24th 7:19am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 67
SF Bay,California, USA
1982 323i, , R1150RT |
I added the VAC motorsports brace w/ the battery relocation while I was at it. Still don't have the car back on the road yet but my friend that clued me in told me it will feel like a new car. |
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| melloh |
Posted
Tuesday, Oct 24th 8:53am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 434
California, USA (San Jose)
1980 320is, 1991 318is |
if thats anything like the rear strut tower brace... then you might not notice much or anything at all. I have that in mine (BMP's) and have not yet noticed any differences other than peace of mind that it is less likely to sag over time. |
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| redmist |
Posted
Tuesday, Oct 24th 4:53pm [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 991
NY USA
357i , 325i e30 turbo |
The other thing I did to strengthen the area is Iran a peice of square tubing between the rear frame rails, together with a strut brace this "boxes" the rear suspension area and helps prevent twisting. |
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| myersport |
Posted
Wednesday, Oct 25th 2:01am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 184
east tennessee
'82 320iS. '91 327iC |
| redmist wrote: | | ....this "boxes" the rear suspension area and helps prevent twisting. |
Helpful when you'll be pushing a conservative 400+ hp and who knows how much torque!! 
--Dennis |
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| wharthog |
Posted
Wednesday, Oct 25th 2:49am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 68
SF Bay,California, USA
1982 323i, , R1150RT |
Melloh, it is a strut brace but it triangulates the strut towers and the cross member in the floor of the trunk. I had it welded to the trunk floor and it bolts onto the shock towers. It also has a spot for the battery which I now have moved to the trunk. The combination of the strut brace, welding all the cracks in the rear bulkhead and relocating the battery should make a difference because the rear was squeaky, rattly and loose. I'm still waiting to get the car back from the welder... |
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| melloh |
Posted
Wednesday, Oct 25th 9:19am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 435
California, USA (San Jose)
1980 320is, 1991 318is |
ah yes. sounds identical (if not the same) as the one advertised/sold by TEP. I actually bought that one, but decided against drilling into the shock tower and opted to get the BMP one and bolt an alum box for the batterey. Perhaps not AS rigid... but the difference isn't enough for me to notice for many reasons (i'm not experienced enough, the car doesnt have that much power, and haven't had the opportunity to really push it that far.... yet ;o). Plus, i actually ever get really serious and actually NEED to beef up ridity, my cousin is a mechanical engineer and said hes willing to help out - would be a fun and educational experience for both of us!
PS: I'm assuming you no longer care to take a jaunt in my car, but I certainly would love to see your car!!! I have yet to even SEE a 323 in person (I did pass a euro 316 from mexico when I lived in san diego, though), let alone ride in one and experience that baby six. Mmmmmm.. I'm drooling already. |
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| imaradiostar |
Posted
Saturday, Oct 28th 9:05pm [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 910
Nashville, TN
81 323i, 82 525i, 85 524td, 90 535i |
BMW sells a factory repair panel for this area- I have yet to price it.
jamie |
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| wharthog |
Posted
Wednesday, Nov 1st 1:23am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 73
SF Bay,California, USA
1982 323i, , R1150RT |
Sorry about the ride melloh I just went for the Alpina springs... I'll IM you about the rest. |
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| MayanArch |
Posted
Wednesday, Nov 1st 1:56am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 1182
Florida, USA
Baur E21 2.7 1982, Baur E30 318i 1985, 323i 1978 |
| melloh wrote: | ah yes. sounds identical (if not the same) as the one advertised/sold by TEP. I actually bought that one, but decided against drilling into the shock tower and opted to get the BMP one and bolt an alum box for the batterey. Perhaps not AS rigid... but the difference isn't enough for me to notice for many reasons (i'm not experienced enough, the car doesnt have that much power, and haven't had the opportunity to really push it that far.... yet ;o). Plus, i actually ever get really serious and actually NEED to beef up ridity, my cousin is a mechanical engineer and said hes willing to help out - would be a fun and educational experience for both of us!
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Actually.....I would love to hear his opinion on the E21 as a structure. Although, a structural engineer would be ideal. |
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| melloh |
Posted
Wednesday, Nov 1st 10:45am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 441
California, USA (San Jose)
1980 320is, 1991 318is |
I haven't actually commissioned him to anything yet. There is no predictable future as to when I will request his expertise, unfortunately. The good news is that my e21 is slowly getting better. still gradually narrowing down the power-sap problem. |
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| jrcook320 |
Posted
Thursday, Nov 2nd 8:43pm [Edit] [Quote] [IMS] [View car] |
Junior Member
Post nr. 1
Van Wert, OH
'81 320i |
| MayanArch wrote: |
Actually.....I would love to hear his opinion on the E21 as a structure. Although, a structural engineer would be ideal. |
A mechanical engineer is ideal, a structural engineer could tell you how to safely construct a bridge. I'm a mechanical engineer and I don't see that there is much need for a straight rear strut bar since the shock towers are not subjected to much, if any, lateral force in hard cornering, therefor there is minimal lateral deflection of the rear strut towers. All a straight bar can do is apply force in the lateral direction. Since the wieght of the car is supported by the strut towers, there may be some lateral deflection if the vertical force applied causes a moment (eg. twisting force about a pivot point)on the towers. This all depends on the structure of the car and where the load on the shock tower is distributed which is obviously a complicated problem to solve.
From my observation, a hard turn can cause a twisting force between the floor of the car where the subfram is attached and outer most shock tower. The subframe will pull away from the car on the outside of the turn, while the outside shock tower will deflect upward. This would in effect stretch the structure between the 2 mounting points. If the brace is triangulated at the cross member at the base of the trunk, I think that would help absorb much of the forces applied during cornering.
In the front suspension, the top of the strut is what actually controls the camber of the wheel. When a lateral force is applied to the wheel (at the ground), this creates a bending moment about the control arm ball joint and there is a force that pulls the strut tower outward.
All that said, I just made a rear strut brace last week. I did notice a squeek that I had has now disappeared, but now that I've thought about it more I'm going to add on to it so it triangulates the towers with the trunk floor. I have a CAD drawing or a .jpg of the shock tower plates if anyone is interested.
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