Slon Workshop E46 M3 Carbon Front Triangulating Reinforcement Kit

[Obioban]

I'm trying to hold off posting any impressions till I've driven it a week or two (so far, overwhelmingly positive), but there's no doubting this thing functions-- my car used to creak/click as I pulled out of the driveway (the angle transition from road to driveway, causing the chassis to flex)-- no longer.

[George Hill]

No Texas sun + garaged, I guess?

Likely the case, still interesting to see how the different regions affect cars.

[9kracing]

Looks amazing installed. Awesome write up, makes me want one.

[terra]

Likely the case, still interesting to see how the different regions affect cars.

Yeah I'm in basically same climate as obioban, and I haven't had to replace the cowling on any of my E46s. It's definitely a bit faded on my M3 now, but not cracked and falling apart like some pictures I see.

For that matter, I haven't had to replace the rear window molding yet either.

[bigjae46]

Yeah I'm in basically same climate as obioban, and I haven't had to replace the cowling on any of my E46s. It's definitely a bit faded on my M3 now, but not cracked and falling apart like some pictures I see.

For that matter, I haven't had to replace the rear window molding yet either.

F body cars in TX suffer from melted door grabs. Grab the handle to close the door and get a handful of stick black goo on your hand. Not fun.

[Obioban]

Just stumbled upon this picture of the OE "BMW Performance" strut tower brace for the e46, and it made me not sure sure I agree with people that say this thing doesn't look OE, including with the clear anodized alu strut tower mounts 😛

[bigjae46]

Just stumbled upon this picture of the OE "BMW Performance" strut tower brace for the e46, and it made me not sure sure I agree with people that say this thing doesn't look OE, including with the raw alu strut tower mounts 😛

Not sure I would say the Slon bar looks OE...it looks high quality and could be OE.

[C///M]

If you look at some of the stuff BMW has produced more recently: F8x carbon strut brace, F97 carbon strut brace, F87 M Performance hood and fenders; in my opinion the stuff from Slon both looks OE and looks like OE quality.

[Obioban]

I’ve been driving this for around 10 days now, so I thought I’m post up my thoughts.

In short, this brace is everything I hoped it would be. The car rides better, handles better, responds faster, and is quieter—and the changes are not subtle. Steering is more precise/consistent/accurate. I knew I was in for a good time just pulling out of the driveway—the car used to have clicks run through the chassis as the chassis twisted from the angle of the driveway to the angle of the street, and the interior plastics changed shape. Now, no longer—completely silent.

I’ve been racking my brain to figure out how to convey what the experience change is like, and I came to what I think is the perfect analogy.
BMW E46 Convertible 10,500
BMW E46 Coupe (w/folding seats) 12,500
According to BMW, the non M coupe is 19% more torsionally rigid than the non M vert. We don’t have numbers for the M vert (we know the M3 coupe is 18,500 nm/deg), but it’s probably a safe assumption that it’s also ~19% less rigid than the M3 coupe.

This brace has measured an increase of 18-20%, depending on the car—so it’s bang-on identical to the increase in going from a vert to a coupe.
If you’ve driven both vert and coupe e46s, you know the exact difference this brace makes, and you’ll know it’s not at all subtle—the more rigid chassis car rides better, handles better, turns in better, has better feedback, is quieter, and is more responsive.

Or, to a less extreme scale, if you’ve driven the same car before and after a roll cage is installed, this is a similar change in feel.

Interestingly, I have not detected any of sizzle change Bry5on mentioned—and I’m pretty hyper focused on steering feel in cars (as in, I never wanted a newer Suburban after it went EPS because I couldn’t deal with the lack of feel—in a freaking suburban). I’m not sure what the difference is there—maybe it comes down to a camber/caster/toe setting difference? Either way, I’ve only found all aspect of steering (and everything else) to be improved.

I feel like I already covered this, but, to reiterate, build quality is off the chart. All the CF is perfect, all the alu parts are beautifully machined, everything fits perfectly, everything is actually engineered (not anywhere near a given in aftermarket car parts), and it looks great. This is an expensive part, no doubt—but it’s expensive for a reason. I doubt the profit margins on this are unusually high.

All told, I freaking love it. I have zero regrets, and highly recommend it. I need to make time to get the SLON Workshop rear bulkhead installed ASAP—not because the car feels unbalanced in any way, but because I want more of this improvement, and I want it now!

[heinzboehmer]

I drove Bry5on's car last weekend and I totally agree that it's not a subtle change. First thing that came to my mind is that it felt like my E82.

Steering response was the most noticable change for me, even just around town. With the brace, the car immediately settles into turns, which is a pretty crazy feeling in an E46. I'm used to feeling the front turn in and then having the rest of the car follow and settle into the turn, but the brace seems to eliminate that delay.

You should definitely get the rear brace installed soon. But I do have to say that it's not as noticable of a change. It definitely made the rear a lot less twitchy, but you have to be pushing the car more to feel the benefits compared to the front brace. That being said, I still haven't gotten tired of flooring the car mid corner in an attempt to upset the rear and just having it hook up and go. Excited to hear your thoughts on how the combo of front and rear braces feels.

I'm pretty sure that front brace will end up on my car too sooner or later.

[nyc951]

Obioban

Thanks for the review. Given how well the SLON brace works, it stands to reason it is actually doing a lot of “work”. It’s actually functioning and dealing with the forces of a moving car. So any ideas on fatigue life?

[terra]

I wish my M3 was in good enough condition to justify this

[Nate047]

Obioban

Thanks for the review. Given how well the SLON brace works, it stands to reason it is actually doing a lot of “work”. It’s actually functioning and dealing with the forces of a moving car. So any ideas on fatigue life?

I don’t think composite materials fatigue like metals, it’s probably just done if it gets cracked or damaged in any way, but more likely will last the lifetime of the car if nothing happens to it.

[Bry5on]

I wish my M3 was in good enough condition to justify this

I mean, my wagon is my DD with shit paint and over 220,000 miles…

[jet_dogg]

I’ve been driving this for around 10 days now, so I thought I’m post up my thoughts.

In short, this brace is everything I hoped it would be. The car rides better, handles better, responds faster, and is quieter—and the changes are not subtle. Steering is more precise/consistent/accurate. I knew I was in for a good time just pulling out of the driveway—the car used to have clicks run through the chassis as the chassis twisted from the angle of the driveway to the angle of the street, and the interior plastics changed shape. Now, no longer—completely silent.

I’ve been racking my brain to figure out how to convey what the experience change is like, and I came to what I think is the perfect analogy.
BMW E46 Convertible 10,500
BMW E46 Coupe (w/folding seats) 12,500
According to BMW, the non M coupe is 19% more torsionally rigid than the non M vert. We don’t have numbers for the M vert (we know the M3 coupe is 18,500 nm/deg), but it’s probably a safe assumption that it’s also ~19% less rigid than the M3 coupe.

This brace has measured an increase of 18-20%, depending on the car—so it’s bang-on identical to the increase in going from a vert to a coupe.
If you’ve driven both vert and coupe e46s, you know the exact difference this brace makes, and you’ll know it’s not at all subtle—the more rigid chassis car rides better, handles better, turns in better, has better feedback, is quieter, and is more responsive.

Or, to a less extreme scale, if you’ve driven the same car before and after a roll cage is installed, this is a similar change in feel.

Interestingly, I have not detected any of sizzle change Bry5on mentioned—and I’m pretty hyper focused on steering feel in cars (as in, I never wanted a newer Suburban after it went EPS because I couldn’t deal with the lack of feel—in a freaking suburban). I’m not sure what the difference is there—maybe it comes down to a camber/caster/toe setting difference? Either way, I’ve only found all aspect of steering (and everything else) to be improved.

I feel like I already covered this, but, to reiterate, build quality is off the chart. All the CF is perfect, all the alu parts are beautifully machined, everything fits perfectly, everything is actually engineered (not anywhere near a given in aftermarket car parts), and it looks great. This is an expensive part, no doubt—but it’s expensive for a reason. I doubt the profit margins on this are unusually high.

All told, I freaking love it. I have zero regrets, and highly recommend it. I need to make time to get the SLON Workshop rear bulkhead installed ASAP—not because the car feels unbalanced in any way, but because I want more of this improvement, and I want it now!

How much did you end up paying for this?