heinzboehmer's 2002 Topaz 6MT Coupe

[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

[Bry5on]

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.

[Slideways]

Hello Heinz,

When you de-pinned and re-routed your post cat O2 harness was the wiring long enough to accommodate the OEM Euro wire guide/connector mount? My harness is not long enough to use the wire guide/mount, and I am trying to determine if I somehow did not fully extend the harness or if the shortage is to be expected.

Thanks.

D-O

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.

[heinzboehmer]

Hello Heinz,

When you de-pinned and re-routed your post cat O2 harness was the wiring long enough to accommodate the OEM Euro wire guide/connector mount? My harness is not long enough to use the wire guide/mount, and I am trying to determine if I somehow did not fully extend the harness or if the shortage is to be expected.

Thanks.

D-O

Hmm, mine feels like it should be long enough, but I accidentally didn't buy all the necessary euro parts when I did it, so I didn't end up using them. My wires are currently just tucked into the transmission harness clips/zip tied out of the way.

I think Bry5on did it the same way I did and also installed the euro stuff? Not sure if he extended the wires though.

[D-O]

Hello Heinz,

When you de-pinned and re-routed your post cat O2 harness was the wiring long enough to accommodate the OEM Euro wire guide/connector mount? My harness is not long enough to use the wire guide/mount, and I am trying to determine if I somehow did not fully extend the harness or if the shortage is to be expected.

Thanks.

D-O

[heinzboehmer]

Didn't even punch yourself in the face, as per tradition.

Oh man if the knob had popped off when I was trying I absolutely would have.