Black & Tan 332iT

[Bry5on]

What do you suspect the camber loss is? My initial inclination would be to say stiffen it up. But, for those who really want maximum performance out of these, you can get an alignment to contract these negative externalities.

Dropping a pound, while I don't know the percentage decrease from factory, should allow for more steering feel I'd presume. If you went this route, you could likely design the nuckle to “give more” performance IE Ackerman (maybe?) to offset the performance losses from lack of stiffness.

Of course, it's entirely up to you. Seems like the lighter design is also the easier build. Combined with your proposed CA design that makes the car more bump compliant, it feels like the more cohesive package. If the camber loss is similar to stock, then your net package will be an improvement over stock in weight, steering, bump compliance and maybe Ackerman.

You can basically interchange weight and rigidity as a benefit as the rest is the same. Otherwise strut flex can be adjusted for in an alignment while you can't align weight out of the system.

Yeah good points, I'm thinking about it similarly. One caveat: adjusting more static negative camber comes at the cost of braking performance. Camber loss looks like about .25 degrees in an absolute max-G corner with a sticky tire.

For percentage weight reduction:
245/40/17 tire: 25lb
17x9 apex wheel: 17lb
brakes: 28lb
e46 spindle, hub, heat shield: 15lb
damper: 8lb?
other stuff: 5lb? (control arm affective weight, spring effective weight, sway link, sway effective weight, etc
total: 98lbs

So 1lb is 1% of the front corner's sprung mass.

The stiffer part is also a bit more money, and it's taller than my plastic printer can print (time for an H2D??) so I can't do a full prototype unfortunately like the lightweight one.

I'm also maintaining the factory e46 M3 Ackerman setup as closely as possible. I adjusted the trailing arm pickup point along the virtual Ackerman line that intersects the car centerline at something like 400% of the wheelbase. In theory I can add a tiny bit of Ackerman before I run into the brake rotor, but not much. The newer cars use the dual ball joint trick to dial in more Ackerman while staying well away from the brake rotor. Since my car isn't lowered, I'm also not dropping the LCA and tie rod pickup points at all as the roll center height is pretty dialed in from the factory - not looking to change that.

[YoitsTmac]

What do you suspect the camber loss is? My initial inclination would be to say stiffen it up. But, for those who really want maximum performance out of these, you can get an alignment to contract these negative externalities.

Dropping a pound, while I don't know the percentage decrease from factory, should allow for more steering feel I'd presume. If you went this route, you could likely design the nuckle to “give more” performance IE Ackerman (maybe?) to offset the performance losses from lack of stiffness.

Of course, it's entirely up to you. Seems like the lighter design is also the easier build. Combined with your proposed CA design that makes the car more bump compliant, it feels like the more cohesive package. If the camber loss is similar to stock, then your net package will be an improvement over stock in weight, steering, bump compliance and maybe Ackerman.

You can basically interchange weight and rigidity as a benefit as the rest is the same. Otherwise strut flex can be adjusted for in an alignment while you can't align weight out of the system.

[Bry5on]

Okay, so I have a dilemma. I got back to work on the custom suspension knuckles. As a reminder, I'm targeting the non-m steering ratio, the later model replaceable beefy wheel bearings and a stiffer overall knuckle. Ideally, we do all that with an unsprung weight reduction.

I'd been pursuing 3D printed aluminum, but was juuust shy of making the loads close with the safety factor I wanted. Then I remembered that even 3D printed materials can be heat treated for better properties. Once I punched those properties in to my analysis, the loads closed with some margin. So we're back in the game, after receiving the printed parts I'll just need to do a multi-hour ~450C oven heat treat followed by a quench, then a handful of hours at 100-150C for accelerated aging. The e39/porsche style steel inserts still need to be very strong, 4340 for those.

So back to the dilemma. I've been hemming and hawing about putting a second strut mount up above the first one ever since I saw the amount of camber loss that happens from strut bending (the primary source of camber loss, as it appears). I decided to take some inspiration from the M4 GTS, but figured I could do better by using 3D printing. The F80 M4 GTS knuckle:


This knuckle uses a second strut clamp and some ribs to connect directly back to the wheel bearing. So how can we do better? Well, because we're going to be 3D printing these, we can leave internal voids in places that would never be able to be machined and we can box this entire section out. This should significantly stiffen/support the strut which will provide less hard corner camber loss and also better damper motion (because it's not actively being bent nearly as much). BUT it adds 1lb to each corner, which means I'll effectively come in at the same weight as the stock e46 M3 knuckle, whereas before I was dropping a pound. So what do you all think I should do here, lightweight or stiff?


edit: Here are the heat shield options as well. One simple, one ducted. And as you can see, the gusset acts as the heat shield to protect the strut from radiation:

[Bry5on]

Short on time so the rest of the updates will have to wait. But in the meantime, the Tesla Model X hitch adapter will fit the BMW receiver if it is 1) bored out a little in the aluminum section and 2) clearanced a little bit where the blue is in the photo below. Party time, doing our family e39 touring this way.




3D scan, Tesla hitch: https://s.digital3dcloud.com/space/f...lang=en&loop=1

3D scan, BMW hitch: https://s.digital3dcloud.com/space/f...lang=en&loop=1

Preview, remember this project?

[Bry5on]

What is your cutoff like? I had been strongly considering NHK retrofits for my sedan but this is the first bad review i've heard.

These specifically, which seem to offer a pretty level cut:

https://sfbay.craigslist.org/sby/pts/d/santa-clara-bi-led-headlights-for-bmw/7822160299.html

Yep, that’s the cutoff from about 5-10 feet away. As you gain distance, the cutoff looks more and more extreme. It’s hard to describe, as it’s not as obvious or bothersome statically on a perfectly flat road, but as you accelerate/decelerate or go through undulations, you’re very aware of the cutoff. I guess you could say it’s distracting. I’ll keep tweaking to see if I can find a perfect height setting, but no luck so far

[Kevin]

What is your cutoff like? I had been strongly considering NHK retrofits for my sedan but this is the first bad review i've heard.

These specifically, which seem to offer a pretty level cut:

https://sfbay.craigslist.org/sby/pts/d/santa-clara-bi-led-headlights-for-bmw/7822160299.html

[IamFODI]

I’m not exactly a headlight expert, but glare might be the right word to describe it. They’re so damn bright, but the brightness is a little jarring, especially when combined with the cutoff that you CANNOT get into a good spot. The light coming off of reflective signs is very intense, and generally the light coming off of other objects is also intense. I tried a few level adjustments and either you’re blinding cars in front of you, or the cutoff is dropping into the road because of the height of the step in the cutoff. They’d be worlds better if the cutoff was just flat.

My wife’s and my prior Porsches both have/had LED headlights and didn’t experience either of these issues, so I was unpleasantly surprised. These are just as bright, if not brighter, but the execution isn’t fantastic.

I'm no headlight expert either, but the experience you described of light from reflective signs and other objects is what I understand glare means. That was exactly my experience with high color temp headlights. If I ever found myself on an empty highway at night and flicked on my high beams, a good sized sign would be hard to see past.

Not surprised that Porsche's OE headlights mitigate these issues. I'm sure that's an example of the benefits of something that's engineered more-or-less as a whole from the ground up. Higher color temps will always cause more glare and eyestrain, all else equal – but I'm sure managing the beam pattern can do a lot to compensate.

[Ramage]

Thanks Bry5on

My car really likes v31 of the Mullet Tune™ I was on v26 prior and while cold starts were never hard for my car it would be somewhat lumpy for forty five seconds to a minute first thing in the morning then it would smooth right out. With v31 the car does not have the lumpy cold start and I am also not detecting as strong of a fuel smell from the exhaust (my car is catless) while I let it warm up.

[Bry5on]

If you like projects I'll mail you my G20 projectors and their pinouts

I don’t do enough night driving to make this a priority unfortunately! If these continue bothering me though, I’ll reach out. Thank you.

[YoitsTmac]

If you like projects I'll mail you my G20 projectors and their pinouts

[Bry5on]

Sounds like those are crap, because the stock headlights are not very good

Glad to hear the review, though, as I've been debating LED conversion to take weight off the nose.

See my note above about your marshmallow headlights.

Worth noting that almost all of the weight reduction is from replacing the ballasts with 3D printed ones. If you’re targeting weight reduction, eliminating them entirely and wiring direct would be the best move. What I did is sort of an 80/20 solution that preserves the factory looking engine bay but drops at least 80% of the weight. The LED headlight itself is about the same weight as the HID+igniter.

[Bry5on]

How's the glare with those LEDs?

Having tried a good range of color temps for headlights, I think my favorite color temp range is something like 3500-3700 K. Above that, I feel like I start losing more to glare than I gain in resolution.

Automotive xenons are generally what, low-to-mid 4000s K? That's pretty much the highest I'll go for.

I’m not exactly a headlight expert, but glare might be the right word to describe it. They’re so damn bright, but the brightness is a little jarring, especially when combined with the cutoff that you CANNOT get into a good spot. The light coming off of reflective signs is very intense, and generally the light coming off of other objects is also intense. I tried a few level adjustments and either you’re blinding cars in front of you, or the cutoff is dropping into the road because of the height of the step in the cutoff. They’d be worlds better if the cutoff was just flat.

My wife’s and my prior Porsches both have/had LED headlights and didn’t experience either of these issues, so I was unpleasantly surprised. These are just as bright, if not brighter, but the execution isn’t fantastic.

Also note that I have non-m headlights, so mine don’t suffer from the toasted marshmallow reflector issues that the M3s had. Both reflectors came out looking perfect with 240k miles on them.

[IamFODI]

How's the glare with those LEDs?

Having tried a good range of color temps for headlights, I think my favorite color temp range is something like 3500-3700 K. Above that, I feel like I start losing more to glare than I gain in resolution.

Automotive xenons are generally what, low-to-mid 4000s K? That's pretty much the highest I'll go for.

[Obioban]

Sounds like those are crap, because the stock headlights are not very good

Glad to hear the review, though, as I've been debating LED conversion to take weight off the nose.

[Bry5on]

Minor updates:

The mullet is on v31 now, and thanks to karter16 and all his work, we've got cold start all dialed in now. It was honestly close before but it's pretty on the money now. Plus, Heinz's car now runs right on the same file as mine and the three beta testers on the file are all reporting positive results. We did something good. If you're on an existing one and want the latest, reach out and I'll whip a new file up for you.

Second, I've had a broken-mount passenger headlight for as long as I've owned the car. I finally picked up a replacement and decided to do the NHK LED headlight conversion using nextelbuddy's great DIY video (thank you!) with some minor tweaks. The two tweaks:
1) Doubled up the wiring to the low beams (red+green to positive, black doubled-up to negative) as the wire gauge in the BMW wiring is not quite large enough for the LED headlight wattage. It's fine in the HIDs because the bulb itself runs at higher voltage and therefore lower current.
2) I 3D printed plastic ballast replacements to drop the dead weight that would otherwise be sitting there. Overall I think I dropped 3lbs off the nose.

Honest opinion, I'm not in love with these lights. Yes they're WAY brighter but the color temp is bluer, so they seem less effective with the light output to me. The cutoff is also super weird - it's like a step _| instead of a ramp _/. Not super into it. Not so much that it's worth removing them, but I wouldn't do it again. The stock headlights were pretty damn good.









Also, a 55" TV fits great even with the brace left in place: