Rear Chassis Brace

[aloksatoor]

Does anyone make a Hotchkis style under body brace like so for this chassis?

http://www.e90post.com/forums/showthread.php?t=164893 The stock ones two rods bolted on and not as robust looking as the welded piece.

[MightyMouseTech]

The one on my car looks similar to the one in that picture and is made from steel. Not sure how much stronger you are going to make it?!?

[E82MSport]

I found a site that offers the E82 1M rear brace but I'm not sure if it mounts the same.


http://www.ultraracing.my/catalog/in...roller=product

Here are the images of the E92 Hotchkis brace vs stock E92


Hotchkis Brace E92


Here are a couple shots of the E82 stock brace

[MightyMouseTech]

Do NOT get Ultra Racing bars. They are crap.

[E82MSport]

Originally Posted by MightyMouseTech

Do NOT get Ultra Racing bars. They are crap.

I'd never heard of them but thought others might have opinions.

Well I guess you can always fabricate one or have someone do it for you. The design looks simple enough. My only concern would be the mounting point height differences (if there are any) which if there were it would make it slightly more difficult to fabricate with straight tubing. I'm guess there might be because the stock lateral arms are flat plate that would allow flex in order to mount properly.

It would be a fun winter project. Take some measurements, model in Solid Works and have the parts fabricated.

Not sure how to properly measure the increase/difference in chassis stiffness without a surface plate but someone here can probably chime in.

[MightyMouseTech]

Tried all sorts of Ultra Racing chassis braces and sway bars on my smart car. Nothing came even remotely close to fitting, even with severe modifications. Then they would not take them back. Tossed them in the garbage. Lesson learned.

[aloksatoor]

Originally Posted by MightyMouseTech

The one on my car looks similar to the one in that picture and is made from steel. Not sure how much stronger you are going to make it?!?

Just thought tubular stock would make it stronger? I was thinking of a half cage but exploring other options to make the back end a bit stiffer.

[fe1rx]

Originally Posted by aloksatoor

Just thought tubular stock would make it stronger? I was thinking of a half cage but exploring other options to make the back end a bit stiffer.

The purpose of the bracing is not to make the car stronger but to make it stiffer. The OE bracing is logical and functional.

The Ultra Racing braces were designed by idiots, which means they are intended for idiots. Their rear "brace" does literally nothing. Their front "brace" is not triangulated properly. They are ballast.

The back end a bit stiffer? What does that even mean? What "problem" are you trying to solve?

The most logical first step to stiffening the rear of the car would be to hard mount the rear subframe. If you haven't done that first, you are absolutely wasting your time with any other change.

If you want to know if a proposed brace will do anything, rig up a fixture with a dial indicator that measures distance change between the two points you intend to join then see if the distance changes when you jack one wheel. If nothing changes significantly, your proposed brace is useless.

[aloksatoor]

Originally Posted by fe1rx

The purpose of the bracing is not to make the car stronger but to make it stiffer. The OE bracing is logical and functional.

The Ultra Racing braces were designed by idiots, which means they are intended for idiots. Their rear "brace" does literally nothing. Their front "brace" is not triangulated properly. They are ballast.

The back end a bit stiffer? What does that even mean? What "problem" are you trying to solve?

The most logical first step to stiffening the rear of the car would be to hard mount the rear subframe. If you haven't done that first, you are absolutely wasting your time with any other change.

If you want to know if a proposed brace will do anything, rig up a fixture with a dial indicator that measures distance change between the two points you intend to join then see if the distance changes when you jack one wheel. If nothing changes significantly, your proposed brace is useless.

Yep I did mean stiffer. ALready have turner solid aluminum rsfb installed. Even then the rear feels a bit vague on power (drivetrain all stock btw no tune no lsd). Rear suspension is stock msport no M bits yet. Fronts got akg monoballs FTABs. Guessing my b12s are gonna solve the issue (but can't get them installed until my camber plates ship which are backordered for ever).

I never asked about the ultra racing brace but the hotchkis for the e90/e92 chassis which hpa sells. I believe the 2 door came with it but the 4 door did not. THat test you mentioned seems interesting. I might try that out.

[dojk]

http://ultraracing.my

Yes, crap they are.

Ultra racing is a Malaysian product. I am surprised they are being exported overseas besides our neighboring countries such as Indonesia, Singapore and Thailand.

In the local scene, they provide quite a number of braces for the local market. Cars that of low value and are structurally weak (think Proton and Perdua), also the lack of understanding the dynamics of a car's chassis together with brainwashing via media makes them a cheap mod. They are cheap too.

I have been told their factory resembles a back yard.

I believe in marketing tools where they are used to represent the company. For example, they built a E60 Drift car. http://www.ultraracing.my/gallery/in...?/category/388
Up close the spacers used to accommodate the widebody were scary blocks at least 5 inches thick. Now what does that tell you about them.

[chris82]

Originally Posted by aloksatoor

Yep I did mean stiffer. ALready have turner solid aluminum rsfb installed. Even then the rear feels a bit vague on power (drivetrain all stock btw no tune no lsd). Rear suspension is stock msport no M bits yet. Fronts got akg monoballs FTABs. Guessing my b12s are gonna solve the issue (but can't get them installed until my camber plates ship which are backordered for ever).

I never asked about the ultra racing brace but the hotchkis for the e90/e92 chassis which hpa sells. I believe the 2 door came with it but the 4 door did not. THat test you mentioned seems interesting. I might try that out.

My answer is to upgrade everything back there with M3 parts! A complete conversion!

[MightyMouseTech]

Or just dial in a little more rear toe in. Will make the back end a lot more stable.