Anti-mushroom :: Strut tower reinforcement plates

[wjk_glynn]

I just acquired an '08 135i and am very happy with it so far.

But I have to admit I was astonished to learn that the E82 strut towers can be bent upwards (i.e. to "mushroom") after hitting such things as potholes. Apparently it's not as common a problem as that seen on E36/E46 frames, but it still happens. Here's a few example threads:

• http://www.1addicts.com/forums/showthread.php?t=404167
• http://www.1addicts.com/forums/showthread.php?t=476447
• http://www.1addicts.com/forums/showthread.php?t=837446 (Edit: Added on 2013.05.07)

So I was thinking of adding some preventative reinforcement plates and two options I've found so far are:

1. Bimmerworld (bolt-on) http://store.bimmerworld.com/e36e46e...tes-p1219.aspx
   
   
2. Turner (requires welding): http://www.turnermotorsport.com/p-27...ates-pair.aspx
   

If anyone has actual experience with these parts (from either vendor, or other unlisted option) and their effectiveness in reinforceing their E82, I'd love to hear your comments.

And then as an aside, another option might be to go with aftermarket camber plates, such as:

1. Dinan (street orientated): http://www.dinancars.com/shop/D160-0...es.aspx#page=1
   
   
2. Vorshlag (more track orientated): http://www.vorshlag.com/product_info...roducts_id=199
   

What are folks opinions on the strut tower reinforcement properties of aftermarket plates like the Dinan or Vorshlag (independant of any additional strut bracing)?

Thanks.

Karl.

[Bordia]

Our strut towers are much stronger than an E46 mount and I do not see a reason to have additional reinforcement for our cars for this reason. I have seen many struts bend before the mount does and only in severe impact do they mushroom and crack at the welds of the stock brace mounts.

[wjk_glynn]

Originally Posted by Bordia

Our strut towers are much stronger than an E46 mount and I do not see a reason to have additional reinforcement for our cars for this reason. I have seen many struts bend before the mount does and only in severe impact do they mushroom and crack at the welds of the stock brace mounts.

Hi Bordia,

I agree they're definitely stronger than the E46 mount.

But there's some evidence that it may not be fully licked:

1. Members MrBimmer, Xaeryan, onefastman and katsooba have reported mushrooming -- two from potholes, the others didn't explictly state what happened (Edit: Added reference to katsooba on 2013.05.07)
2. I spoke to Dinan Service in Campbell (CA) and they've definitely seen this happen on both the E82 and E9x chassis - almost always after hitting a pothole or curb. Not to the level of causing cracks, 'just' an upward deformation which causes the studs to splay out a bit. The repair method is the wooden block & 3-lb hammer technique...
3. I also spoke to BR Racing in Los Gatos (CA). They've raced a E82 and for track work they recommend reinforcement... with the Vorshlag plates as the way to go.

Hopefully I haven't come across as unduly alarmist, but I am trying to determine if some preventative reinforcment is worth doing (note that I typically track my cars 4-5 times per year).

Karl.

[Stohlen]

I feel like you're obsessing over a rare issue. Are you going to try to engineer fixes to all of the 135i's rare issues?

[Pyrat 2]

I put the Dinan camber plates on just to help neutralize the under steer. They also act as a reinforcement plate even though I wasn't too worried about that.

[Bordia]

Here are some photos from a E90 335xi I have in strut and spindle were bent up to 8deg of negative camber with very minimal mushrooming of strut mount. Have I seen mushrooming with less suspension damage yes but very uncommon. Ok will have to load them up when I get home my phone won't let me.

[wjk_glynn]

Originally Posted by Stohlen

I feel like you're obsessing over a rare issue...

By nature I'm a bit of a "belt-and-suspenders" type, so you may very well be right.

On the other hand, spending a few hours of labor to fit some form of reinforcement plates (probably in the form of camber plates) might be the right move for me. It's a piece of mind kind of thing...

Karl.

[wjk_glynn]

Originally Posted by Bordia

Here are some photos from a E90 335xi ... will have to load them up when I get home my phone won't let me.

That would be interesting to see.

Karl.

[wjk_glynn]

I bought a set of the Bimmer World and Turner Motorsport reinforcement plates for the E82.

Here's a side by side comparison:




I would hazard a guess and say the Turner Motorsport plates have roughly 50% more surface area than the Bimmer World plates. That's a pure SWAG...

I emailed Turner Motorsport and asked if their plates really had to be welded in, or could they be simply held in place when the struts are bolted up into the towers. Their response was:

"They won’t offer as much reinforcement, but these can be bolted in. I would recommend painting the reinforcement prior to doing that."

Karl.

[3002 tii]

Bump for an update? Also can the Dinan plate be stacked with the reinforcement plate?

Just checked BW's site, their product description says it fits E8x but the title nor the drop down menu has no mention of the E8x.

[wjk_glynn]

I personally haven't yet done any suspension updates, so I've nothing to report right now.

But I'm leaning towards a combination of Vorshlag plates with the Turner Motorsport reinforcements... but I worry about NVH with that combination.

Karl.

[3002 tii]

Originally Posted by wjk_glynn

I personally haven't yet done any suspension updates, so I've nothing to report right now.

But I'm leaning towards a combination of Vorshlag plates with the Turner Motorsport reinforcements... but I worry about NVH with that combination.

Karl.

In that case let me know if I can take the BW ones off your hands.

[Nugget]

Originally Posted by 3002 Tii

Bump for an update? Also can the Dinan plate be stacked with the reinforcement plate?

Just checked BW's site, their product description says it fits E8x but the title nor the drop down menu has no mention of the E8x.

Why not use just the Dinan plates?

[3002 tii]

Originally Posted by Nugget

Why not use just the Dinan plates?

Why not use both if you can? I've got both camber plates and reinforcement plates on my other car without any issue. For any additional $20 it's cheap insurance.

[timhatimay]

I have the Dinan Camber Plates on my car, and really like them. They offer no increase in NVH and no sacrifice in comfort, and with M3 arms can get up to -2* of camber (plus/minus a bit). The increased surface area and reinforcement to the bottom of the strut tower is a great bonus. This was an additional factor that helped make up my mind since I live in NYC (with really crappy roads). Keep in mind with each plate you add underneath you are raising the car height a little bit.

I also took an additional step to help against mushrooming, but on the top side. The M3 (or 1M) strut tower brace goes to all 3 studs from the strut, and covers the entire top of the strut tower. I have no scientific evidence, but I think this should be a good prevention to mushrooming the tower. It bolts down nice and sturdy to the struts. Now that is really belt and suspenders...reinforcement to the top and bottom (and both have other performance benefits). It also really reduced flex in the front of the car. This was a subtle change for turn in and response in the front of the car, especially for quick transitions.

Tim

[awns729]

Does anyone know if either of the 2 reinforcement plates (or any others) fit E88 convertibles? Bimmerworld said that my E88 may have a different strut tower area than the coupes so theirs may not fit. Was wondering if anyone had experience with this? Thanks!

[MightyMouseTech]

I will be combining the Dinan camber plates plus the 1M strut tower brace which also has a reinforcement plate that goes on top. Plate sandwich!

[Ski Killset]

I doubt putting a bunch of heat into the tops of the strut towers is going to help. The Minis are notorious for this and a bolt in pinch plate style is fine. Looking at the 1's towers, I doubt it will ever be a problem.

On a race car that is running 1000# springs, solid bushings and splined swaybars would cause more problems. But most cages should be tied in to the strut towers to absorb the loads.

On a street car and even occasional HPDE car I would be suprised