Rigid Collar for 1M

[Aqua]

Anyone tried this on their 1M? Wonder how are the results.

It is made my Spoon

https://www.flickr.com/photos/rla044...7633273470912/

[Artemis]

Apparently somebody already did:

https://www.flickr.com/photos/rla044...7633273470912/

[MDORPHN]

Might make sense for a track car, but too much NVH for the street.

Neil

[EldRick]

... too much NVH for the street.

Actually, it might well reduce NVH, by better coupling the subframe and other potentially-moving bits to the greater mass of the frame, rather than allowing them to resonate and vibrate.

[flzrider]

Interesting. I would like to hear someone's experience with these to gauge how much benefit it provides.

[MDORPHN]

Originally Posted by EldRick

Actually, it might well reduce NVH, by better coupling the subframe and other potentially-moving bits to the greater mass of the frame, rather than allowing them to resonate and vibrate.

Have you ever driven a car with solid mounts?

They substantially increase NVH.

Neil

[EldRick]

Totally different issue. Solid motor/tranny/suspension mounts replace rubber bushings with hard material. This simply makes an already solid attachment-point better.
(Maybe.)
AFAIC, the jury is out on this one - a lot of positive reviews, but there are a lot of positive reviews for the $60 Turbo Intake Fan, too...

[eeghie]

solid connection is replaced with marginally softer but still non compliant material, so i'm skeptical on this product doing anything more than what a regular torquing or alignment would do, assuming something was misaligned or loose to begin with.

[ilikebmxbikes]

Originally Posted by MDORPHN

Have you ever driven a car with solid mounts?

They substantially increase NVH.

Neil

Solid mounted subframe does not induce much NVH. The m3 gts, f10 m5 and f8x are solid mounted. Solid diff, motor and tranny bushings do however.

[Em/1]

Too me this appears not to be a change to solid mounts, but rather substituting a more sturdy solid mount for a less sturdy/sloppy one. At no point in the film, at least, did they show a rubber mount being tossed. Looks like it would have no downside other than time and money; hard to know how much upside!

[PeteA]

For the rear subframe? That would be fine for NVH. Is there a kit available?

[TXmtrhed]

To me the point of the collars is two fold:
1) to make sure the subframe is centered up under the mounting bosses and 2) to make sure the subframe does not shift leading to suspension alignment changes.

Neither one is a big concern since I don't know of any cases of movement with the subframe properly torqued in place. The examples shown don't show any movement, only slight misalignment which would be dialed out by a proper alignment job. And the rubber bushings will compress laterally no matter how sturdily the subframe is located.

In my mind the key advantage of the solid SFB is the decrease in vertical compliance which affects the effective spring rate especially with stiffer springs. The collars won't have any effect on this.

[PeteA]

Well, here is my two cents. Other than lining things up right the first time things are bolted up, to my logic there are negatives. For eg:

You're adding a some thickness between each bolt head the mounting point. By doing so, you would effectively be losing a thread or two in bolt depth into the hole.

Given that the bolt is now sitting a few threads further out, you would need to over-toque all the bolts where a collar is placed to make up for it.

You're adding a material that is soft enough to 'fill in' the gaps from just torquing , I am sure they would elongate from driving about under load.

Like the others said, torque all your shit properly and dial out the variations with an alignment. The flex in the rubber bushings are better tackled instead. I recommend solid subframe bushings, adjustable rear toe arms (rogue/dinan) and some nice dinan monoball front control arm bushings.

[Snertz]

IMO dialing out the variations with an alignment is just a band-aid that doesn't address how alignment changes as the suspension compresses; Static wheel alignment square to the body but with a subframe that isn't square would result in a wheel motion that isn't the same on both sides.

I think there is some merit to the mod, though not as much as Spoon makes it out to be.

http://www.rigidcollar.com/bmw-bmw-1...e88-front.html
http://www.rigidcollar.com/bmw-bmw-1...-e88-rear.html

Cheaper option here : http://bit.ly/1tIkYPn anyone wanna be a guinea pig?

[eeghie]

Originally Posted by Snertz

IMO dialing out the variations with an alignment is just a band-aid that doesn't address how alignment changes as the suspension compresses; Static wheel alignment square to the body but with a subframe that isn't square would result in a wheel motion that isn't the same on both sides.

...

Cheaper option here : http://bit.ly/1tIkYPn anyone wanna be a guinea pig?

Fair point but does not necessarily mean that factory misalignment produces noticeable handling deterioration; Or the other way around: 150 SGP$ (~114$) seems a reasonable price to test for yourself if perfect sub frame alignment produces any noticeable handling improvements: who's first? @Advevo?

And if factory misalignment could be noticeable, wouldn't car manufacturers want to fit these collars on press cars?

[ALEJANDRO]

where do you buy these?