Black & Tan 332iT

[Bry5on]

I had to use the spacers included with my SS exhaust to get the braces to fit properly with the oversized pipes. Any idea how the convertible brace would work with the SS oversize dual pipe section two?

I had to use spacers with my SS exhaust too, it fits very poorly. Reused the same spacers with the cabrio brace, no issues there, although I made these spacers myself, so I can’t comment on the SS specific hardware.

[D-O]

Fits great! Rough math says that the 4 cabrio fasteners will see about 60% of the load of the original 8, and this brace will certainly be stiffer inherently. So an upgrade on paper. No real noticeable change, but it's definitely not less stiff. It's getting hard to do the driveway test as the car isn't making much creaking in the door sills unless it's pretty extreme.

I had to use the spacers included with my SS exhaust to get the braces to fit properly with the oversized pipes. Any idea how the convertible brace would work with the SS oversize dual pipe section two?

[Bry5on]

Wow, thanks for your contribution Bry5on, great read and development! I know there's a guy in europe selling a brace that bolts the shock tower and fender rail. Do you think that would add even more rigidity?
https://drifthq.com/products/tech-53-bmw-e46-bolt-on-strut-tower-reinforcement-kit?pr_prod_strat=e5_desc&pr_rec_id=64e6463eb&pr_r ec_pid=8087369875643&pr_ref_pid=8006405423291&pr_s eq=uniform

Funny, this is actually what I started on, which led me to the project I chose instead! I went to visit George to grab a scan of that area to design a brace just like that.

It just so happened that the car I was scanning had hit a big pothole on one side so I could see exactly how the metal deformed. Once I’d given that a good look, I was pretty convinced that the flexiness that cracks that strut tower seam sealer is actually coming from where I braced, not directly from where the cracks were forming. So we ran the experiment I posted about earlier to validate the theory. At this point, I think that the brace above would be a bit redundant. I’d bet it would provide incremental gains, but likely much smaller than the invisible ones I installed. Plus, it wouldn’t be invisible So for now I’m pretty happy with where it is.

[enjoy_m3]

Wow, thanks for your contribution Bry5on, great read and development! I know there's a guy in europe selling a brace that bolts the shock tower and fender rail. Do you think that would add even more rigidity?

https://drifthq.com/products/tech-53-bmw-e46-bolt-on-strut-tower-reinforcement-kit?pr_prod_strat=e5_desc&pr_rec_id=64e6463eb&pr_rec_pid=8087369875643&pr_ref_pid=8006405423291&pr_seq=uniform

[Bry5on]

I wonder if there would be additional benefit to be gained by epoxy bonding these? (3M 73333, etc.) I'm not really sure if there's any risk of movement over time around the bolt holes?

From a stiffness performance perspective, technically yes although I’d wager you’re capturing 99.9% of the value with just fasteners. I think on balance you could make an epoxy/rubber joint a little lighter though. Given that I don’t actually know the loads here, tough to say!

[karter16]

3) I got to installing the fender brace with these awesome new rivet nuts (definitely recommend).

I wonder if there would be additional benefit to be gained by epoxy bonding these? (3M 73333, etc.) I'm not really sure if there's any risk of movement over time around the bolt holes?

[Bry5on]

Installing with wet POR-15 or is that an epoxy? Thank you for all you do!

I did POR-15, probably lots of options though! When I did this at work I’d use a zinc chromate primer instead. Honestly not sure which is better.

[ethan]

Installing with wet POR-15 or is that an epoxy? Thank you for all you do!

[Bry5on]

I'm very excited for this! Having felt some extra chassis rigidity with the rear brace I now want as much as possible! I love that this solution is entirely invisible when installed! Which rivnuts did you use? (Or have I missed that somewhere?)

Thanks very much for sharing the sendcutsend cart!


Sent from my iPhone using Tapatalk

These bad boys, installed in a .5” hole: Metric Low-Profile Rivet Nut, Tin-Zinc-Plated Steel, M8x1.25 Internal Thread, 15.2mm Long

https://www.mcmaster.com/91230A011

Don’t do what I did and accidentally go one step too far with your stepped drill bit on the first test hole! But if you do want a low risk ‘test’ hole, the topmost one does the least structurally.

[karter16]

Ok, great successes!

3) I got to installing the fender brace with these awesome new rivet nuts (definitely recommend).

I'm very excited for this! Having felt some extra chassis rigidity with the rear brace I now want as much as possible! I love that this solution is entirely invisible when installed! Which rivnuts did you use? (Or have I missed that somewhere?)

Thanks very much for sharing the sendcutsend cart!


Sent from my iPhone using Tapatalk

[Bry5on]

Ok, great successes!

1) Last night I loaded karter16's custom binary that logs extra values over CAN. So far it's working great, even with extra data like lambda integrator, and now I can finally stop bothering the D-bus constantly while I'm driving. Thank you! Datalog of a drive here: https://datazap.me/u/bry5on/kartercan-log?log=0&data=23

2) Today I installed v2 of the exhaust brace. I'd noticed around 3300rpm that a bit of vibration was still coming through, so I modified the design to use the non-m e46 exhaust hanger bushings. Mild-but-still-there improvement. I also discovered that the thin brace to the exhaust has cracked. I guess next time I'll try Ti or just design a weld-on bracket.




3) I got to installing the fender brace with these awesome new rivet nuts (definitely recommend). Fitting up:


Rivet nuts installed:


Bolted in:


After installing the brace, I repeated the earlier experiment but as below with the car 1) in the air and 2) lowered straight on the ground. I left the Slon brace installed for the most conservative test. Measuring displacement here I saw .001"


So what's the verdict? A nice improvement again! The front feels in line with the rear now after the recent work I did back there, and so far it's most noticeable on pothole and sharp road impacts. There's less harshness and the steering feels almost a bit lighter. There's yet another step of less vibration in the steering wheel when driving over not-smooth pavement, although not as drastic a change as the Slon brace. I expect that once I get a chance to put the car through its paces, it'll be even more stable and consistent during cornering, putting the suspension to work instead of the chassis.

If you want to order/recreate this on your own car, click this link and get a set for yourself! https://cart.sendcutsend.com/chn7orju3zid The job took about 4 hours and involves removing the bumper, headlights, fenders at the very least. So budget for a full day as I work pretty fast.
edit: the cart above is for two sets. Either reduce the quantity to 1 each or get one for a friend!

[Bry5on]

Good updates with the braces. Out of curiosity, did the front clip have the windshield and lower subframe brace installed?

Good questions, it did not. I wouldn’t expect much of a change from those two though.

I’m planning a modified re-run of this experiment when I pull my fenders off. Basically set the dial indicator up and watch it as I lift the car up and place it back on the ground. We’ll see what happens!

[discoelk]

Good updates with the braces. Out of curiosity, did the front clip have the windshield and lower subframe brace installed?

[Carbonvert]

Alright, here’s a link for those in the US where you can purchase this v-subframe brace directly if you so desire: https://cart.sendcutsend.com/styxqbkx1nth

Reminder, this link is not me selling anything, I make no money on this, and I’m not affiliated with sendcutsend other than really liking their service.

Just stumbled onto this. Thank you for sharing. I'm thinking this will compliment the redish v3 kit being installed right now

[Obioban]

Seems to now be NLA.

Go, team!

... glad to have mine in hand...