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Discussion Starter #1
How important is the addition of a strut tower brace on a car that's tracked 5-6 times a year? Not from a performance standpoint, but in terms of enhancing structural integrity. I have Dinan Stage 3 and will track with street tires on OEM wheels.

Related question: My left/right front camber numbers came out to -1.5 and
-0.9. I'm going back to the dealer to try to adjust. Is this kind of mismatch common? Is this another reason to add a strut brace, after the dealer readjusts? Thanks in advance.
 

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EdP said:
How important is the addition of a strut tower brace on a car that's tracked 5-6 times a year? Not from a performance standpoint, but in terms of enhancing structural integrity. I have Dinan Stage 3 and will track with street tires on OEM wheels.

Related question: My left/right front camber numbers came out to -1.5 and
-0.9. I'm going back to the dealer to try to adjust. Is this kind of mismatch common? Is this another reason to add a strut brace, after the dealer readjusts? Thanks in advance.


That's the exact reason I added the strut braces, to keep the car from flexing. I know a guy who autocrosses his 540, uses R tires etc, who swears the gap in his passenger rear door jamb has grown by 2mm. My dinan guy also told me that they have seen several 540's with track time with broken spot welds in the rear deck. I figure it's a little structure insurance.

As for the alignment, while mine is not exactly the same l and r, it's not 0.6 degrees off, more on the magnitude of .2 or so iirc.
Mike
 

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I think a .2 difference is done usally for the car to track straight so it does not pull from side to side...something to that affect, my alignment guy explained it to me a long time ago I forgot how he phrased it exactly but it's that kind of thing. Because most roads round to the edges for drainage reasons.

I would do the braces so if nothing is the chances of creeking lessin.

Do you have the dinan camber plates? If so I dont' know if that can be corrected since they are fixed mount. I would deffinitly look to have both sides over 1.5 neg camber.
 

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Discussion Starter #4
Thanks for the imput guys. The tech I spoke with on Friday said he should be able to fiddle with it some. What's strange is that my "before" alignment settings are almost the same as the "after," even with the addition of the camber plates. Doesn't make sense to me:

Before After
left -1x33' -1.34'
right -0x57' -0x54'

The second number, I've learned, is minutes, with 60 minutes per degree. So
-1x33' is roughly -1.5 degrees.
 

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EdP said:
Thanks for the imput guys. The tech I spoke with on Friday said he should be able to fiddle with it some. What's strange is that my "before" alignment settings are almost the same as the "after," even with the addition of the camber plates. Doesn't make sense to me:

Before After
left -1x33' -1.34'
right -0x57' -0x54'

The second number, I've learned, is minutes, with 60 minutes per degree. So
-1x33' is roughly -1.5 degrees.
Ed,

There was another board member where the Dinan plates were installed wrong (I think rotated a 1/3 of a turn), so make sure that they are installed such that they yield the maximum negative camber. http://www.m5board.com/vbulletin/showthread.php?t=39509

Chuck
 

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CSBM5 said:
Ed,

There was another board member where the Dinan plates were installed wrong (I think rotated a 1/3 of a turn), so make sure that they are installed such that they yield the maximum negative camber. http://www.m5board.com/vbulletin/showthread.php?t=39509

Chuck
Yup! There are three possible rotations for the plates, since they have 3 holes. A mechanic who guesses has a 33% chance of getting each side positioned correctly. If you pop the plastic covers off the top of each strut tower, you should see the "center" strut rod end and nut pushed about 3/4" towards the motor. In stock form, it is in the geometric center of the strut tower clearance hole.
 

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Discussion Starter #7
Chuck, thanks for that thread. But it's still a mystery. Each strut rod end angles towards the center of the engine, and the "elongated holes" of each plate are oriented the same way (i.e., at 3 o'clock and 9 o'clock). I still don't understand why my left front camber started at -1.5, and why the camber on both sides is essentially unchanged even after the plates were installed. I'll try to have someone else take a look at it tomorrow.

:confused:
 

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EdP said:
Chuck, thanks for that thread. But it's still a mystery. Each strut rod end angles towards the center of the engine, and the "elongated holes" of each plate are oriented the same way (i.e., at 3 o'clock and 9 o'clock). I still don't understand why my left front camber started at -1.5, and why the camber on both sides is essentially unchanged even after the plates were installed. I'll try to have someone else take a look at it tomorrow.

:confused:
Ed, My only guess at this point is that the "before and after" figures were from the alignment machine: i.e. the before is when it was first read after being hooked up to the machine, and the after figure is after the alignment (i.e. setting the toe-in as this is the only adjustment in the front) is done. In other words, both values are with the camber plates installed. This would make sense due to the fact that the camber didn't change. Note that very small changes in the values are typical since it is very touchy.

Chuck
 
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