heinzboehmer's 2002 Topaz 6MT Coupe

[heinzboehmer]

Wait, what am I doing. The current vents are a terrible design.

The air should be coming in through the mount. Should be able to channel a lot more volume that way. Guess I'm used to thinking in traditional manufacturing ways, where features within a part are a pain to make. 3D printing is the perfect tool for that kind of thing, however.

Okay well, new version coming soon. I should really stop iterating on this stupid thing...

[heinzboehmer]

Been driving around with the latest revision of the phone mount for a couple days. Think this is the last iteration of it for a while. Works great and I don't really see any more glaring issues. Here's a quick summary of the changes I've made since the last post about it:

• Phone mount surface tilted 10 deg down and rotated 1.5 deg CW
• Dash support leg angled out towards dash to make them more orthogonal
• Added draft to the surface facing the door to fix slight interference (~1mm)
• Added zip tie holes along dash support and main arm to hold future charging cable
• Reworked top tab geometry to integrate displacement limiting features
• Added air vents through the body of the mount

Have yet to see if the vents do anything. Figured that I should add them since the AC vent is right there and it might be nice to be able to cool my phone on hot days, especially if it's in direct sun. The intake of the vents is through the back of the mount and they come out the front. Did it this way to keep as much stiffness as possible (at least I think this way is stiffer?). Cross sectional area of the vents is tiny, but I think a smaller amount of directed air is better than a splat from the vent. Plus, even with the vent pointed all the way up, it really only manages to hit the bottom ledge of the mount.

Couple pictures of this latest version:




The only thing I am going to modify is the material for the top and bottom "bumpers" (the features that actually hold the phone). They're currently printed out of 95A TPU (Polymaker PolyFlex TPU95-HF), which works fine, but is a bit too slippery. I can see my phone shifting around a bit after some driving. Planning on printing those out of the softest filament I could find: Recreus Filaflex 60A. Should up the coefficient of friction significantly and help grip the phone a bit better.

Seems like it'll be a bit of a challenge to print, but we'll see how that goes. Gonna leave some links I found about printing with super soft filaments here, for future reference:

https://forum.bambulab.com/t/setting-the-extruder-pressure-for-soft-tpu/40022

https://forum.bambulab.com/t/adjust-tension-on-extruder-wheels-for-printing-very-soft-tpu/4897

[heinzboehmer]

After all that messing around with the shifter mass damper, it ended up sitting higher than it did when I originally installed it. The damper itself wasn't visible through the boot, but the clamp it came with was. So I got some lower profile clamps to replace it with (Oetiker 16700044, 7mm band, 31.4-34.6mm ID).

Original on the left, new on the right:



And installed:



Pretty much impossible to tell the damper is there now, nice.

[heinzboehmer]

Can you do a RHD one LOL?

I bet if you mirror it horizontally it'll be plug and play, but I don't have a way to test that version over here in the US. I'll post the CAD to karter16's CAD thread soonish, but I want to get some good seat time with it first in case I want to tweak it further. Unfortunately haven't had a chance to drive the car around with the final version at all, but should be able to get some driving in later this week.

I'm a big fan of the concept of the induktiv Qi charger plus wireless CarPlay, but the execution really needs improvement. As in, the phone slides around and off the Qi happy spot. Even when it is on target, the charger can't quite keep up with a phone doing navigation.

I'm very much hoping with Qi2 coming out, they do an updated version with "magsafe". It would make me 100% satisfied with that solution. It really like the idea of, leave phone in pocket for short drives (and still have it on screen via wireless carplay), or drop it on the qi charger center console for longer drives.

I agree that it's a great concept, but not the best execution. Didn't like the E82 version either. I don't think I'll use this mount too often though, mostly just on longer trips.

Any concerns about the phone potentially going out the window?

Ha, you're not the first person to ask that. Definitely a risk, but I basically never drive with the windows down, so it should be fine. I might try to find a low profile 90 deg USB cable that I can attach to the mount as a sort of "retaining strap". Just for that little extra bit of security.

Same here, for now its coming out and getting replaced with cupholders LOL

Yeeeah, the one I bought for the E82 was only installed for a little while. If you don't have nav, the sunglasses holder cubby under the radio is a great spot for a custom wireless charger install.

[0-60motorsports]

I'm a big fan of the concept of the induktiv Qi charger plus wireless CarPlay, but the execution really needs improvement. As in, the phone slides around and off the Qi happy spot. Even when it is on target, the charger can't quite keep up with a phone doing navigation.

I'm very much hoping with Qi2 coming out, they do an updated version with "magsafe". It would make me 100% satisfied with that solution. It really like the idea of, leave phone in pocket for short drives (and still have it on screen via wireless carplay), or drop it on the qi charger center console for longer drives.

Same here, for now its coming out and getting replaced with cupholders LOL

[George Hill]

Any concerns about the phone potentially going out the window?

[Obioban]

I'm a big fan of the concept of the induktiv Qi charger plus wireless CarPlay, but the execution really needs improvement. As in, the phone slides around and off the Qi happy spot. Even when it is on target, the charger can't quite keep up with a phone doing navigation.

I'm very much hoping with Qi2 coming out, they do an updated version with "magsafe". It would make me 100% satisfied with that solution. It really like the idea of, leave phone in pocket for short drives (and still have it on screen via wireless carplay), or drop it on the qi charger center console for longer drives.

[Mike RT4]

Can you do a RHD one LOL?

[heinzboehmer]

For this week's project, I decided to make a phone mount, as I didn't like any of the products on the market. The design had three hard requirements:

1. Able to be (un)installed in <5s. I only ever want the mount to be visible when my phone is installed, so it has to be easily stashable.
2. Phone has to be above the dash. I really like the placement of the iDrive hump in the E82, so wanted to it to be at about that height.
3. Mount cannot block other interfaces. Can't be in front of cluster, radio, A/C, etc.

My initial approach was to attach a base to the dash bar and have some interface (likely magnetic) come out through the left side dash vent. Should be very solid like this and hidden when the main mount body isn't installed. Some pics of the development of that section:





The idea is sound, but the vent itself has a lot less space than I originally envisioned. This means that I would likely need to use the vents that point at the door as stiffness reinforcements for the long thin cantilever coming from the dash bar piece. So I decided to scrap the dash bar idea and instead make something that just attaches to the vent.

After some iterations, I came up with a design that attaches to the vent very securely:





With that figured out, I moved on to figuring out the ideal location for my phone. Some pics of that process:




And the final product next to a couple earlier prototypes (I think the "scaffolded" one on the left is particularly cool looking, but ultimately was less stiff and bulkier than the ones on the right):




Installed on the car:




Side view of an earlier prototype:



I'm super happy with how this turned out. Installation is extremely easy, there is practically zero vibration when moving and it's entirely out of the way of everything. Roadtrips should be much nicer now!

[heinzboehmer]

Heard my airbox start rattling again so went and checked on it. Turns out the bushings I printed rode up on the posts so much that they were no longer doing their job:



This is what they looked like (well, two of them, the third is lost forever in the engine bay abyss):




They've certainly taken some damage! This might be one of those "replace at every oil change" things. Oh well, they require 0.5 g of material to print and can be installed in 5 min, so not super worried about the short replacement interval.

To combat the riding up issue I created a V2. Part is the same as before, but with a base, which should keep them in place:



I made the base the same thickness as the grey "weatherstripping" on the unfiltered section and notched that out for clearance:



Everything installed:




Let's see how long these last!

[heinzboehmer]

Impressive. Was the middle also the best position by feel?

Oh yeah I forgot to talk about that. The answer is no. The top position has a very slight improvement in feel over the middle one. Feel doesn't change nearly as much as rattle amplitude, so I decided to keep it in the middle.

[D-O]

Impressive. Was the middle also the best position by feel?

[heinzboehmer]

Ran a quick experiment today to get an idea of how to tune shifter mass damper.

The shifter rattle is most prominent above 6k rpm in third gear, so I found a place where I could go WOT in third from about 4k to redline. I also (mostly arbitrarily) chose the following three positions for the damper:

1. As far down as it would go



2. As far up as it would go before slipping off the shank



3. Roughly in the middle of the previous two positions



Most of the force that is oscillating the shift lever back and forth should be coming from the selector rod and carrier, as the rest of the points are suspended with rubber bushings. Felt to me like the selector rod would play the biggest role, so my guess was that the higher the damper sat, the more it would dampen the rattle, since more force would be needed at the selector rod joint to move the shift lever through the same angular displacement.

Testing consisted of me setting the damper to one of the heights and then doing a WOT pull. I recorded each pull with my phone (placed in the same spot) to try and quantify the rattle.

I put the audio from the three pulls through a low pass filter to isolate the rattle and then tried to match the gain across all three tracks. That last part was more of a guessing game than anything else, since I couldn't turn off the dynamic mic gain on my phone, but still good enough. Here's the spectrogram comparison with a rough rpm guide overlaid (rattle is the red areas):



The most prominent thing to note is how the amplitude of the rattle is pretty much constant all the way from 6k to 8k in the top position, grows with rpm in the bottom position, but it is really only loud from 6.5-7.2k in the middle position. Not at all what I was expecting! But my anecdotal observations do match the data. The middle position seems much better tuned.

So, turns out my hypothesis was wrong. Guess the carrier contributes more than I expected? Either way, glad I ran this experiment and learned something new.

I'm pretty sure there's more to be tuned, but I can't think of a way to do it on the street without spending hours doing the same thing with much smaller vertical displacement increments. I have been kinda wanting to go back to the dyno now that I have the wideband in my headers, so that might be the perfect opportunity to do this. Can just hold the car at 6.5kish rpm in third and move the damper up and down to find the sweet spot.

Anyway, gonna leave it in the middle position for now and maybe I'll mess with it again in the future.

[repoman89]

The rear O2 sensors are different lengths for Euro vs US which means the DME harness is most likely different (definitely different part number):

Euro
Oxygen sensor BOSCH/L=750MM 1 11781405324
Oxygen sensor L=480MM 1 11787832035

US
Oxygen sensor BOSCH/L=1075MM 1 11781406621
Oxygen sensor BOSCH/L=935MM 1 11781406622

The US ones are longer, so you would think it would reach with some extra slack. The location of the O2 plugs might not be in an ideal spot to clip them in under the car with the euro cable box.

I put the Euro DME harness in my car a while back because I was unhappy with how my hacked US one turned out. Easy job. Three of the four sensors are on US cars but have to be rotated around, and I had to buy the 480mm one new (Bosch generic from eBay for $50). The harness used to be a couple hundred bucks which was a no brainer to me. Last I checked it was like $600 now which is pointless.

[D-O]

The engine harness is not long enough to reach the locations where the plugs should fit in the euro harness. The US O2 sensor harnesses themselves are longer than euro so you can make it reach without cutting, it just won’t fit into the factory euro clips perfectly.

This is where I am at ^^.

Thanks to all three of you guys.

D-O