Proboner's Z4 build thread

[proboner]

Gonna give a bit of context for how I got here, but for those of you who don't care, feel free to skip ahead to the pictures. TLDR- After much research and consternation I bought an e89 z4.

So this last March I vaguely began searching for a new (to me) car. I still had 2 cars I needed to dispose of to facilitate the purchase, so I wasn't trying to pull the trigger, but was definitely looking to decide what the car would be. In May I ran into a car that I hadn't previously considered, but that completely opened by eyes to a new option... a 2007 Z4M.

I already owned a 2003 Z4 3.0 6-speed and figured the M would be too similar and wouldn't provid that new car excitement. However this car was the perfect setup: black exterior, red interior with carbon trim, in gorgeous condition. I went to look at it and was intrigued, but wasn't quite ready to pull the trigger. Another enthusiast ended up buying it a couple days later, but at this point an upgraded Z4 had been added to the list of potentials.

A month later yet another black on red Z4M popped up nearby, and this time I was a bit more prepared to pull the trigger. I went to test drive it and frankly was not impressed. The torque curve below 6k is atrocious, and it just really doesn't feel all that quick... my S52 swapped e30 feels much faster. With the underwhelming test drive and the dealers refusal to come down from their $21k asking price, I decided against a purchase. Again I wait.

Now I've been vaguely looking at E89s for a few years, and with Z4s now in focus I stepped up my search a bit. The thing I knew I'd have a problem with is finding a manual with the N54 motor. Expanding my search across the country, I still only found a few candidates with a clutch pedal. At one point I ended up renting a DCT 35is for a weekend to see if it would scratch my itch, but I just find them too boring to drive with an automatic. I knew it HAD to be a manual.

And then it hit happened. On Monday July 27th, as I was doing my nightly rounds of the for sale websites, I found the holy grail. An absolutely mint 2013 Z4 sdrive35i M-Sport, manual, black exterior with red interior. It was GORGEOUS. To this day, the most beautiful stock Z4 I've ever seen. So gorgeous I've saved all the pictures... take a look!






I knew I had to have it, but the car was in NC while I'm in CA. I emailed the dealership that night and went to sleep and dreamt of cars. I woke up the next morning to an email response with a phone number to call. I called them immediately with no answer and a voicemail indicating the dealership was closed for the day due to a hurricane. I left a VM and then sent a follow up email. I hadn't heard back by later in the day so I called again, to no answer. Wednesday morning I tried again with yet another no answer, but a response via text indicated the car had already sold! WTF! I'd had my chance and managed to miss it!

Over the next couple days I began mourning the loss of this potential ownership, but noticed the car still kept coming up in my searches. By this point I was going a bit insane! I texted the salesman a few more times asking why the ad was still up, but he assured me every time that it was sold. Eventually I said fuck this, and called the main dealer number directly. Another salesman picked up and informed me that there was an interested party, but that they were still getting an inspection blah blah blah. After a bit of a run around, the car ended up selling for real the following Tuesday.

So now I was convinced. I'm pretty wishy washy about this stuff, constantly agonizing over what the correct choice is, but this had been different. All the other cars vaguely interested me, but this was something I NEEDED. In my sorrow I started grasping at straws. I even came on here and posted a WTB thread in the FS section. As I'm sure all of you are aware, this forum isn't particularly busy, so I wasn't hopeful that I'd receive a response to my request. Well hilariously enough, a few days after posting there was a single reply to my thread, indicating they would consider selling the exact car I had described! I went back and forth with the owner for a bit and on August 14th flew up to Washington and drove it 15 hours back down to the Bay Area. The PO did a LOT of performance work on her, so thankfully I don't have to! But there are still things that need doing.

So with that long unneeded story out of the way, let me introduce you to Mazikeen. She's a 2011 Z4 sdrive35i, black on red, 46k miles. I was unhappy to find that she's not very well optioned, most notably no idrive/screen or heated seats (my gfs favorite feature of my current e85). The PO thankfully upgraded to an m-sport front bumper and 2018 M3 wheels, and it does have adaptive sport suspension which is actually very comfortable as a DD, but sits the car WAY too high and floats like a boat. The key area of improvement was performance. Within the last 3k miles the following were added:

• Pure DD turbos
• AR Design 3" catless downpipes
• VRSF Race intercooler
• PSP outlets
• MHD tuning flash
• 335is clutch
• VRSF charge pipes
• PR ignition coils
• 450lph Walbro fuel pump
• Index 12 injectors
• Tial BOV
• New OEM HPFP

Currently pushing 18psi which I guess is around 450whp. Also did a walnut blast, new PCV, and water pump/thermostat.

[proboner]

First things were first, she needed to be lowered. Did a bit of research and figured I'd try the easy/cheap button and start out with H&R springs. And boy did they do the job, ride height is just right!








But dear lord the ride! It's actually not harsh with stiffer springs, it doesn't bang around or feel jolting. It's just so. damn. bumpy. The stock struts/shocks cannot manage rebound properly with these springs, which can cause a resonant effect. There have been at least two times of note where I've hit a succession of medium sized bumps which have disrupted the car enough that I've almost flown out of my seat! Plus they make my gf nauseous any time she rides in it, so unfortunately they must go. After doing much more research, I decided I'll be going with ST XA coilovers in the near future, as they're made by KW with only a slight difference in material (galvanized steel vs stainless) and are essentially on par with KW V2, which isn't even available for our platform. This give rebound adjustability, which is exactly what seems to be needed right now.

Also did a few smaller mods to get the color scheme on point. Painted kidneys, roll hoops, side markers, and grille inserts gunmetal to match the wheels.








And of course what would this thread be without a list of future mods

• Android screen to replace missing idrive- ordered
• ST XA coilovers- ordering
• 35is brakes
• 19" bronze wheels/tires
• M-sport rear bumper
• Dual Varex internal bypass exhaust?- still deciding
• Paint correction and ceramic coating

[Asbjorn]

Nice build!

Actually if you want to keep the H&R springs, I could help to order some custom dampers for you. Not sure about the shipping cost from China though. I did custom dampers myself to run a combination of Eibach rear and OEM front setup, to dial out some understeer on track. Did H&R list the spring rates? I actually have a used set lying around that I never installed.

[proboner]

Thanks!

I ended up calling H&R to figure out the spring rates and they told me they don't divulge that information and also pointed out that since they're progressive, they're "not sure". Riiight. Either way, ended up ordering the ST XA coilover setup this morning. Very excited to get those bad boys in place!

[Ichiro]

Nice list of performance mods. I've never seen an e89 with 513M wheels, looks tough with those tires and drop.

I've ordered a set of ST XA coilovers too, keen to install and feel the difference it makes in handling.

[proboner]

Yeah the drop is pretty much perfect and surprisingly the tires clear all around. Nary a scrape to be heard! Are you also waiting 3 months to receive your ST XAs as well? Just got a shipping update for 12/15/20!

[Ichiro]

Originally Posted by proboner

Yeah the drop is pretty much perfect and surprisingly the tires clear all around. Nary a scrape to be heard! Are you also waiting 3 months to receive your ST XAs as well? Just got a shipping update for 12/15/20!

Daaang that's a long wait. I ordered mine from Tunershop on the 11th of July and was told to expect a 6 week wait for KW to build it. I was just given a tracking number on the 9th and it should be in my hands next week... hopefully.

[proboner]

Little video of the exhaust, mainly for posterity's sake. The ones just a cold start, idle till the vacuum actuated exhaust valve opens, then a couple small revs. AR catless downpipes with stock exhaust. Big fan of how quiet yet mean it sounds. I really like it as is, but I have these two Varex mufflers sitting in my garage that are just PERFECT for this application. Decisions, decisions...

Added some captions to help you keep up with what's happening

[turbo16lbs]

What size tires if you don't mine me asking?

[proboner]

Fronts are 245/40/18, rears are 275/35/18

[proboner]

Little photoshop of the wheels I'll likely be swapping on...

[proboner]

Can't deny that she's one hot chickadee

[AR_Motorwerkz]

Great build so far. She sounds great!

[proboner]

Not a ton of building so far in the thread, so thought I'd give an update on things in the mix...

Android screen came in a while back.


Purchased some carbon fiber vinyl to cover the interior pieces while they were out, but realized I accidentally bought an Anthracite tinted version. Not sure if I'm going to keep it this way or not, but it was my first time wrapping and there are a few imperfections anyways.






I think the thing I'm must upset about is that it's not integrated with the car at all, which isn't something I realized when I purchased it. Since this car didn't come with idrive, it doesn't have the corresponding LVDS cable, which essentially integrates the screen with the car. It makes the home screen pretty useless. The aftermarket idrive controller that comes with it is pretty garbage as well. It's obviously meant to work with the now essentially useless home screen, and even when using it in the correct way, it's super slow to react and doesn't respond to inputs half the time.

I have started down the path of figuring out how I'm actually going to use it... just setup hotspot tethering with my phone and downloaded the Android App to the screen and synced with my Spotify account. We'll see how it goes. Still a little bitter about this one.

Continuing to agonize over what wheels I'll be throwing on her. Currently have genuine M3 513m's, which everyone seems to LOVE... except me. I know I want 19's, which these are not, and honestly I'm just not a huge fan of the design. At this point I'm stuck between 2 potential options:

19" Vertini RFS1.7 in brushed dual bronze with chrome lip, which has already been posted above


19" ESR SR07 in matte bronze


The ESR's are actual the wheel I was planning to put on this car before I even bought it, but then those Vertini's caught my eye and do look pretty darn good in the photoshop. Think I'm leaning back towards the ESR's though.

Either way however, there is one consistent piece between both photoshops that is not currently on the car, but that will be before I get new wheels/tires, and that is the brakes. When I installed the H&R springs I noticed that the rotors are toast and there's a definite surge in the pedal when stopping from high speed.

Have seen a number of big brake setups for these cars but after doing research I realized the major issue with most is that really there are only options for the front. The rear having the electric parking brake pretty much precludes most larger brake setups in the rear, and I kind of hate the idea of having huge front brakes and normal sized rears. Also, I require red calipers, and the other economical options seem to be blue or throw up green. Eventually decided to go with a 35is setup, as they're larger than what I currently have, (and actually have larger rotors than even the 235i msport setup) and are relatively economical.

Bought Zimmerman rotors and Akebono pads all around from FCP Euro, calipers all around from a shop out of FL, and caliper rebuild kits from Napa Auto Parts. Honestly I'm a little miffed about the rotors... the description on FCP says they have OEM style aluminum hats, but upon receiving them they definitely do not. Also to note, the caliper rebuild kit was WAY cheaper from Napa and they even had a kit for the rears, which no one else seemed to.


First step was to disassemble the calipers for powder coating. I was going to actually powdercoat them myself, as I have all the pieces to do it. The part I cannot do, is the sand blasting, which after I get that done, I may as well fork over a few bones to get the whole job finished. They'll be going out to the coater on Monday...


As I agonized over wheel selection, I happened across a 19" setup with a similar look to the ESR's, for very cheap. Bought them for a test fit just to get an idea of the true look.




Not bad, and I do like that it's a bit understated. Decided I definitely want to go with a taller tire though. Personally, I've always thought the overall wheel/tire diameter seemed too small on these cars. My current setup is 245/40/18 front and 275/35/18 rear, which is larger than stock and surprisingly doesn't scrape despite sitting SUPER low with these springs. The tires on the mock up wheels are 235/35/19 front and 265/30/19 rear, which is pretty darn close to the height of the current setup, but they look like absolute rubber bands on those 19s, and just too small for the car in general. I plan to try running 235/40/19s and 275/35/19s. Will wait until I get the ST coilovers so I can raise the height a little bit to match. AND, with a bit of a heigh increase, I can actually consider running a front lip.

In non-z4 news, I put the previous Emortal RS wheels back on the e30 and she looks marvelous again


Got a picture of the ladies together as well.


And lastly, took this shot during the fires here in CA a month or so back... pretty insane.

[proboner]

Have a very exciting update today! I ordered ST coilovers from Vivid Racing on August 8th, not realizing they were just a middle man and would pass the order to ST for fulfillment. When I inquired on a timeline they suggested I'd be receiving them in mid-December! Needless to say I was a bit miffed, but what are you gonna do? So I accepted my fate and waited.

Well this afternoon I went outside to get something out of the car and opened my front door to a large package sitting on the front porch. Sure enough, they'd come a full 6 weeks early! SUPER STOKED right now and had to post, even though no one's active on here.

Plan to start the install this weekend, which will align perfectly with the 35is brakes.




Sitting with the brakes, awaiting install

[Mmdt101]

Originally Posted by proboner

Have a very exciting update today! I ordered ST coilovers from Vivid Racing on August 8th, not realizing they were just a middle man and would pass the order to ST for fulfillment. When I inquired on a timeline they suggested I'd be receiving them in mid-December! Needless to say I was a bit miffed, but what are you gonna do? So I accepted my fate and waited.

Well this afternoon I went outside to get something out of the car and opened my front door to a large package sitting on the front porch. Sure enough, they'd come a full 6 weeks early! SUPER STOKED right now and had to post, even though no one's active on here.

Plan to start the install this weekend, which will align perfectly with the 35is brakes.




Sitting with the brakes, awaiting install

Thanks for letting us follow along! Beautiful build! Curious, where'd you pick up the Android from? Was it a difficult install? It's on my list for this winter. I'm located in MO, so my '11 e89 will likely be waiting for a random sunny day to take out again.

Have you thought of adding rear view camera or backup sensors?

[tranquility]

"proboner" lmao

Srsly though, nice collection of Bimmers.

[proboner]

Originally Posted by tranquility

"proboner" lmao

Srsly though, nice collection of Bimmers.

Haha I used to be a Ford Probe guy... the name's just too good to give up!

[Ichiro]

Congrats on the delivery. Looking forward to reading about your ride impressions!

[proboner]

Thanks, I'm quite excited as well, if it's not obvious. Vivid Racing never updated on shipping status or anything, it just *appeared*.

[proboner]

Got the calipers back from the powder coater today


And now they sit with the rest of the parts awaiting install this weekend

[proboner]

Originally Posted by Mmdt101

Thanks for letting us follow along! Beautiful build! Curious, where'd you pick up the Android from? Was it a difficult install? It's on my list for this winter. I'm located in MO, so my '11 e89 will likely be waiting for a random sunny day to take out again.

Have you thought of adding rear view camera or backup sensors?

Hey, sorry I missed your comment earlier. I bought my Andriod screen from Hifimax. I've already posted some of my gripes above. I know I'm not using the screen to it's full potential yet, but I'm mostly upset that because I didn't have a screen from the factory I don't have the LVDS cable which means the screen and car basically don't communicate at all. This makes some of the main user interface completely useless. I'm sure there are workarounds and ways I can make it better, I just need to do some research.

Install can be done in a day, although I did mine a couple hours at a time over several days. DaveZed has a very thorough install video that you can follow to make sure you're on track, as the instructions provided are not particularly clear. He's also put together a video for installing reverse sensors, which aren't on my agenda at this point.

Thanks for the comment!