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      01-20-2018, 09:11 PM   #17
Lieutenant Colonel

Drives: '17 328d Sport Wagon
Join Date: Sep 2016
Location: Bay Area, CA

iTrader: (2)

Reducing Ambient Noise
One of the more annoying traits of my car was the noise, vibration, and harshness (NVH). This became more apparent when I had Dinan Shockware installed, giving myself a stiffer ride. I started to notice more creaks, rattles, and road noise in general.

To combat the NVH I tried the popular Dynamat. I covered both the outer skin of the doors as well as the inner frame of it in dynamat. I didn't have a roller, but did use the back rounded end of a screwdriver to apply pressure across it after hitting it with my heat gun. With just the Dynamat alone, I really didn't see any improvement in NVH, which was disappointing.

As I did more research, I found that Dynamat is primarily made to dampen vibrations, not necessarily block any noise. I would need a blocking material (mass loaded vinyl - MLV) to really reduce the noise. While looking for MLV I came across Second Skin Audio's Luxury Liner Pro (LLP), which is MLV on a mat of foam.

Unlike Dynamat, LLP doesn't have any adhesive on it, and actually functions better when allowed some movement. I figured I could hang it on the door frame, between the inner frame and door card. To do this I grabbed some heavy duty hook and loop and attached one side to the door, just beneath where the window opening is, and the other to the LLP to hang it from there. After hanging the sheet of LLP, I cut it in the shape of the door card, then made cutouts for the door card mounting pins, and various cables that'd have to be routed through. When I tried to put the door card on, I found out that I couldn't do it. The LLP wasn't as flexible as I thought and was putting up resistance. To remedy this, I made relief cuts in the LLP where features of the door card were applying more pressure. This worked well and allowed me to get the door cards on.

Initially bought enough LLP to just do the doors, and if that showed a decent improvement I'd probably buy more to do the floors. Unlike Dynamat, LLP definitely reduced the ambient noise in the cabin. I could easily hear conversations in the vehicle better. I was happy enough with the level of improvement, that I actually decided I didn't need to do the floors. LLP and Dynamat are fairly heavy stuff, and you can end up adding a bunch of weight if you try and apply it everywhere. Keep that in mind!

After learning to take apart my door cards, I noticed that some of the rattles I was hearing was from the plastic pins that hold the door card to the door frame. These pins snap into a plastic claw-type opening, but once they're in there they can rattle around. I shimmed the excess space between the clips and the door card mount, and this surprisingly reduced a lot of rattles.

Similarly, I found that some of the footwell trim pieces use the same clips for mounting. Those too got the shim treatment and improved.

Another annoying rattle I found was in my dash trim (the large main piece). One of the metal mounting pins in it wasn't secured well. Some glue fixed that one.

The funniest rattle I had wasn't actually with the car itself, but with an accessory I put on it. I kept hearing this rattle up high, and thought it was something in the sunroof track. One day, I decided to watch some of my dashcam footage, and heard the rattle very clearly. I then realized that the buttons on my dash cam (Thinkware F770) were rattling! Some clear packing tape put lightly over the buttons (so they can still be depressed and return) solved that one!

Like many others with M-Sport trim, I had creaking coming from the rubber door trim rubbing on the black piano trim lining the doors. I mentioned this during a dealer service visit once, and they applied felt tape to the rubber trim on my door.

Recently I found out where a creak, that sounds like a rattle, is coming from. For some reason when my front windows are rolled all the way up, the glass and rubber contact at the top causes a creaking. If I lower my windows a couple of millimeters, such that the windows are still closed and sealed (no change in wind noise), the creaking goes away. I'm going to see if I can find some rubber treatment to prevent this.

Chassis Stiffening
In an effort to stiffen my chassis further I decided to try a front and rear strut/support bar. There's been plenty debate on the forums whether this really does anything, and I wanted to see for myself. After seeing BEM-S4's post on them, I decided to go with the KC Design front and rear bars. KC Design was super easy to work with over email and the items arrived quickly from Taiwan.

KC Design Front Strut Bar

Installing the front bar is very easy and straight forward. BMW's documents show the front LCI bolt torque to be 30nm + 90deg, however when I was loosening all the bolts, none of them required close to 30nm of break torque, hrm...

KC Design Rear Bar

The rear bar has some peculiarities for it's install, and I ran into a couple of issues I had to solve during it. When removing the rear cargo mounts to install the rear bar, I found a factory issue, and another source of rattling. It appears as if the factory didn't thread the hole straight, and then cross threaded the cargo mount bolt in it. It actually crushed the threads on the bolt. The cargo mount ring that the bolt is supposed to hold down could rattle around since the bolt never secured it fully. To fix this I mentioned this issue to my dealership during my next visit and they re-threaded the hole properly under warranty. KC Design provides two standoff shims/cylinders to put between the rear mounting holes and the bar. This is to elevate the bar above the rear cargo area trim. On my vehicle these shims were far too short. I went to the hardware store and bought washers to get the appropriate height. Additionally, the bolts supplied with the bar were a bit too short. I ended up getting 45-50mm long bolts, which will allow you to place the original cargo mount ring on top of the bar, and bolt both down.

KC Design Rear Bar Mount (note hint of washer peeking out underneath the black cylinder and factory cargo ring on top)

So how much did the bars change the ride? I'm happy to say that the front bar produced a very noticeable difference. When cornering harder the front end of the vehicle feels more solid and predictable. Additionally, it seemed to improve the steering feel a bit too. Unfortunately, I can't say the same for the rear bar. I really don't notice any difference with it.

In anticipation for an upcoming track day I decided to have the car's alignment changed over the holidays. Earlier in the year I attended a BMW CCA tech session at Edge Motorworks, in Mountain View, where I learned about the effects that an alignment can have and how you'd want to do it for different types of driving. I went back to Edge Motorworks and asked them to align my vehicle for better performance.

They maxed out my front camber, which was only about -0.6deg , reduced the front toe, and reduced the rear toe and camber.

Edge Motorworks Alignment Values

During the BMW CCA tech talk, another member said that the alignment had "transformed" his car's handling. With that high bar in mind, I hopped into my car after Edge Motorworks had finished and, felt underwhelmed. I didn't really notice an immediate difference driving through Mountain View to my next stop. It wasn't until I got on the freeway that I noticed a clear difference. There was much less understeer when going around corners and I had a "eureka" moment. It almost felt unnatural at first, but as I got used to it, I became glad I had this done.

Diesel Fuel Economy
I recently passed the one-year mark with my vehicle just before the holidays. Over that period I drove about 21,000mi, and averaged 35.28mpg. The highest fuel economy I got was 39.94mpg, and the worst was 30.58mpg. I'm sure if I restrained myself to cruising at 75mph instead of 80mph on the freeway I'd improve those numbers.

Crashing an Audi Party, Part II!
One of my coworkers tracks a lot (Cayman GT4), and has been trying to get me out to an event with him. He's a member of the Audi Club, and convinced me to go with him to their Winterfest weekend at Thunder Hill.

You can check out my log/after action report (AAR) of two days at Thunder Hill here.

Photos Makes a Slow Car Look Fast

When I showed up at the event I was wearing my M-School jacket, but underneath I had the 034 Motorsport shirt I got last year at their Winterfest dyno day. My was surprised I had the shirt, and I told him the story of how I crashed the Audi party last year and got it.

My Instructor (Audi TT RS)

The Audi club is a great bunch of guys and very good at helping you learn in an HPDE environment. I wish the BMW CCA GGC did more HPDEs and was better organized (they STILL don't have any upcoming events on their website/Facebook!).

The Dirty Secret to Ceramic Pro's Warranty
One of the stipulations of Ceramic Pro's warranty is that you have an annual inspection done. The warranty states that the Cermaic Pro certified installer that does the inspection will charge a fee for cleaning, polishing, and additional application if required. Now, I knew that way back, and didn't really have a problem with it considering how much I value Jason/Carzwerk's work. I asked Jason to perform the inspection and apply a refresh coat of Ceramic Pro.

At this point I shouldn't be, but I'm always surprised at how fantastic looking my car looks after leaving it with Jason for a few hours. I brought him a filthy car that had just come from a track weekend, and he made it shine! The texture on the cars surface everywhere was just so incredibly smooth!

Additionally Jason went the extra mile and made sure to give my door jambs, and other neglected areas cleaning. He wasn't going to be doing any coating on the wheels, but cleaned them up as well (and they were downright FILTHY with track day brake dust).

After Ceramic Pro Refresh with Carzwerk

New Street Pads
Not wanting to ruin Jason's work, the following weekend I replaced my M-Sport brake pads with a less dusty option. The M-Sport pads work well on the street and track, but the levels of dust they give off is ridiculous! Cleaning my wheels was always a bit depressing, because I knew that within a week they'd be covered in dust again.

EBC Redstuff (top) and M-Sport (bottom) Front Brake Pads

For street pads I went with EBC's Redstuff. I got my set on eBay for $225 new. EBC claims their Redstuff pads are low are low dust ceramic street compound. One thing I thought was interesting, is that EBC puts a really abrasive "brake in" coating on their pads, which is supposed to let you brake well upon initial installation (I suspect it also clears any old pad material off). You're not supposed to bed the brakes till this top coating is all worn down. The brake in coating definitely stops well. It bites very early and hard!

EBC Redstuff (bottom) and M-Sport (top) Rear Brake Pads

There aren't really any good stretches of road to bed brakes near me that you can turn around on and go multiple times, but there are some country roads where you can just travel the length of them bedding your brakes. I chose one of these roads that's 5.5mi long to bed the EBC Redstuff pads. That consisted of me getting up to about 60mph, using medium brake pressure to go down to 25mph, and repeating that a couple of times to get the pad temperatures up, then getting up to 70-90mph (as the road allowed), and braking hard (practiced my threshold braking). Around the last mile of this 5.5mile road, I started to get brake fade pretty significantly, and figured the pads were bedded . The next morning, the brake feel was back to normal since the pads had cooled. I definitely know I can't take these pads to the track!

For street driving I'm pretty happy with the EBC Redstuff pads. The bite is better than the M-Sport brake pads, and the braking power is similar to the M-Sport pads in medium/hard braking. I haven't cleaned the wheels yet (since I've been going on dirt roads the past few weekends), but just looking at the pads themselves, I can see much less dust on them. Also, I haven't noticed any squealing, which was what pushed me over the edge on replacing the M-Sport pads for street driving.