Does anyone have...

[zoner]

A good, clear picture of where the rear sway bar mounts to the chassis on our cars? I'm getting ready to install a 19mm rear bar and I'm trying to envision how to install reinforcement plates in this location. (I have a pretty good idea in my head, I just want to make sure it will work before I start cutting metal.

Thanks!

[BimmerBum]

You are a week early. Next week the sub frame, trailing arms, diff, and exhaust are all coming out. I will be replacing that stock 16mm sport bar with a 22mm Dinan bar and Dinan reinforcements. After a good cleaning.

[zoner]

PRECISELY what I was looking for- thanks, Ed! Do you know if Dinan still makes the reinforcements for this mount? (I already have the AKG reinforcements for the trailing arm mounts)

I was hoping I wouldn't have to do much, if any, actual fabrication, but after looking at this picture, the vision I had in my head is completely wrong. I'm now wondering if I could somehow weld some gussets to the existing factory mount by triangulating the sides and accomplish the same thing...?

[BimmerBum]

Originally Posted by zoner

PRECISELY what I was looking for- thanks, Ed! Do you know if Dinan still makes the reinforcements for this mount? (I already have the AKG reinforcements for the trailing arm mounts)

Nice, I am selling AKG stuff now so if you need anything else let me know.

Last I checked you could still buy the plates from Dinan but you may end up with bushings too as part of install kit.

If you end up with bushings for the Dinan bar let me know. I will have 3 cars running around with 22mm Dinan bars so a spare set of bushings might not be a bad thing to have.

[BimmerBum]

Just pulled the instructions from Dinan, excuse the stain (they came that way).

[zoner]

So, if I understand the diagram correctly, the Dinan kit is just an extra metal plate that essentially 'boxes' the factory mount like so:





If that's the case, I think it would be easy enough to just cut a piece of steel to the corresponding size and weld it in there. After seeing a picture of the mount, the follow-up idea that I had in mind seems a lot more complicated, but it also seems a lot stronger than Dinan's solution. I'm not going to argue with Dinan's engineering and I guess my follow-up idea would have been substantial overkill and probably would have been a little trickier to weld.

That Dinan sheet doesn't happen to have dimensions on it, does it? (I'm thinking not, since it's not really pertinent information, once you've already purchased the product...) Dinan doesn't show the plates on their website (that I could find) but if that is all there is to them, they seem easy enough to fab up and weld in.

[BimmerBum]

Just measured the Dinan plate. It is approx 25.5mm x 51mm x 3.4mm

It sits more perpendicular than you have it pictured and comes all the way down on the lip of the stock bracket.

[zoner]

So, more like this:





And it is just welded top and bottom?


Thanks for the dimensions- this seems easy enough to cut and weld.

[BimmerBum]

Yes... just top and bottom. I am guessing Dinan left the sides open so that mount would not retain moisture and rust.

[anassa]

Hey zoner,

Why all that work for a 19mm bar? I just checked the z3m, it has the same mounting structure as the ti and it came with a 19mm rear stock. I have a 19mm on my ti and haven't had a problem. Admittedly I have not run it hard for a while either though.

[BimmerBum]

Get tires with enough grip on a car that is pushed hard enough and a 15mm bar might damage the mounts.

Originally Posted by anassa

Hey zoner,

Why all that work for a 19mm bar? I just checked the z3m, it has the same mounting structure as the ti and it came with a 19mm rear stock. I have a 19mm on my ti and haven't had a problem. Admittedly I have not run it hard for a while either though.

[anassa]

Originally Posted by BimmerBum

Get tires with enough grip on a car that is pushed hard enough and a 15mm bar might damage the mounts.

Hmm didn't know they where that weak. I have a hard time seeing a m44 with grippy tires doing that to a 15mm sway bar though. I guess I never pushed mine hard enough . I guess its always better to be safe then sorry.

[BimmerBum]

Engine size makes no difference. Say you are running slicks that have a MUCH higher grip level than say a 340 treadware tire. The extra grip is a good thing but it also makes the suspension work that much more, in turn loading the sway bar and its mounts that much more.

Originally Posted by anassa

Hmm didn't know they where that weak. I have a hard time seeing a m44 with grippy tires doing that to a 15mm sway bar though. I guess I never pushed mine hard enough . I guess its always better to be safe then sorry.

[zoner]

Makes sense on the openings for moisture/dirt/etc. It looks like it's about 10ga. steel- maybe I'll cut a few sets of plates, time permitting. Thanks again for all of your help on this, Ed.

Anassa: I'm running Yoko S-Drives, which are pretty damn grippy tires, and one thing I love to do in this car is carve high-speed twisties. I would hate to install a 19mm bar and have that mount fatigue over time or worse, pop in the middle of a hard curve, during a spirited driving session. It's insurance if nothing else. I also have an Eibach 28mm front bar going in at the same time.

[anassa]

Originally Posted by BimmerBum

Engine size makes no difference. Say you are running slicks that have a MUCH higher grip level than say a 340 treadware tire. The extra grip is a good thing but it also makes the suspension work that much more, in turn loading the sway bar and its mounts that much more.

I can understand it in theory and I know better then to doubt you lol (not meant sarcastically in any way shape or form! Especially since I have no formal track time at all!) The reason I mentioned the m44 though was because i thought on corner exit, for example, and accelerating out of a corner a larger 6cyl would also add more stress to that already wound up suspension then a relatively slow m44 (especially with grippy tires)- also seems to be reason the ti isn't as known for ripped sub frame mounts or destroyed sway bar mounting points?

Besides I also ask the question because unless like you mention you are on semi slicks or some high grip track tire there is a low chance of the stock sway bar points failing. So I am wondering if zoner is going to be driving his car in those conditions. - Sorry zoner (I don't know your use of the ti ) it just seems unneeded for a street vehicle.


(BTW sorry for the thead hijack! )