Are solid aluminium subframe bushings WOF legal?

[jin108 25]

As per title looking to get a set for my E90. Would I get called out on this when getting a WOF?

[Michael. 2313]

Check the Low Volume Cert website, under suspension I believe it covers such details. Off the top of my head I think it's okay.

That said, why do you want to do this - road or race car? I'd highly suggest not doing it if you're using it on the road often, it's going to increase vibration and noise somewhat for little gain.

[jin108 25]

Thanks couldnt find anything on there about subframe bushings. Its mainly a road vehicle with the occaisonal track day. I want to change them because under acceleration there is too much squat and at speed the rear can go wandering a bit. Most reviews i have seen say solid SF bushings do not increase nvh. Solid diff bushings are a different story. New M cars now have solid SF bushings too.

[Michael. 2313]

Just did some reading:

Section 4 Modification criteria 4.1

Certification requirement exclusions

A vehicle is not required to be certified to the Low Volume Vehicle Code where a suspension modification is the sole modification, and the following criteria is met, provided that the safe performance of the vehicle is not compromised:

"after-market suspension bushes may be substituted for the originals, provided they are made from an appropriate material such as polyurethane and there has been no cutting or machining of the suspension arms to fit them"

I think on such grounds you'd be okay.

[Apex 693]

Who the heck is going to even notice them. Just fit them and cary on with your life.

I would only ever bother certifying something obvious, like Coil Overs, and even then I would try and get a WOF without one, as my race car does.. the LVVC has so many holes in it its more a joke than anything else.

[Michael. 2313]

Guide lines are fun to stick to though

[Apex 693]

Meh, no one ever did anything awesome sticking to guidelines.

[jin108 25]

Thanks for the replies. Knowing the guidelines is useful because solid bushings take a bit of effort to get in even when using a proper press tool (which i dont have).

If there was even a small chance they were not legal then it would not be worth the effort and would go poly or M3.

[wtbdeath 4]

I think going with solid subframe mounts is a very wise move, it does not increase VNH a lot, as long as you don't put on solid mounts on drive chain .

Solid mounts also decrease the chance of damaged floors if you are talking about E46 or E36

[jin108 25]

Agree but its too much work to install them on the E9x at least. Have been told a hand pressing tool will not work and the subframe needs to be removed.

[KwS 2429]

"after-market suspension bushes may be substituted for the originals, provided they are made from an appropriate material such as polyurethane and there has been no cutting or machining of the suspension arms to fit them"

I think on such grounds you'd be okay.

Im not so sure. It specifically specifies Polyurethane in its example, its dubious whether they would consider aluminium as an "appropriate material".

Either way, as mentioned, its unlikely anyone would notice or care.

[Michael. 2313]

Yeah it's quite a ambiguous statement they have made.

[kiwi328i 118]

Im not so sure. It specifically specifies Polyurethane in its example, its dubious whether they would consider aluminium as an "appropriate material".

Either way, as mentioned, its unlikely anyone would notice or care.

If it were me in this situation, I would argue that Aluminum is an appropriate material, if it were not why would so many companies make them. Bread or jandals I would argue would be less appropriate materials.