BMW Side Impact Protection

At BMW factory in South Carolina there is a Z3 Safety Shell Exhibit that shows off some of the design and technology BMW is using to make these cars as safe as possible. One of the improvements they are especially proud of is the yellow bar you see running horizontally across the door.

It looks simple enough but this bar is designed to protect the occupant by spreading the impact in front of and behind the driver. At the exhibit we were told that this could easily make the difference between walking away from an accident or not.

Okay forget marketing hype, Mike Dwyer saw this device work in real life. “I had someone run a red light and hit me directly on the drivers door at about 35mph. Only a few minor nicks for me, but the M roadster had the back left wheel tweeked and the total bill was almost $12k”

Looking at this picture you can see that the door was the impact zone. But notice the raised ridge (and picture that yellow bar from the safety shell exhibit).

Retrofitting BMW Roll Hoops

Pros: Upgrades both safety and image of pre-98 Z3’s to 98+ standards. Added protection in the event of rollover. Creates framework for additional accessories, like the windblocker.
Cons: Long, involved procedure. Plenty of opportunity to break stuff. Relatively high retrofit cost for what was a no-cost upgrade to the ’98s.
Cost: $633 ~ $840 (not including installation)

If your BMW Z3 does not have rollhoops it may be possible to retrofit them into your vehicle. BMW has an upgrade kit, but it can only be used on Z3s built on or after 1/97. Specifically 1.9 VIN LB83105 and later; 2.8 VIN LC01377 and later. No earlier production will work (and remember — some “1997” cars were actually built in 1996).

There is no external indication of this. The cars made in 1996 and in 1997 look the same. However, the designers clearly thought that the car needed rollhoops and tried to plan for it, even though the hoops were not ready in 1996 and 1997. It looks like some kind of manufacturing error led to the release of the ’96 cars without the hoop supports, but in ’97 they had (at least) started to install the critical braces. In ’98 the hoops became a factory installed option, standard in the US, optional in Europe and other parts of the world.

(Editors Note: Another rumor was that BMW Legal held up the release of the roll hoops, but manufacturing had already made the design changes. So just the hoops themselves with removed from the scheduled production.)

If your car meets the VIN requirements, it means it can be retrofitted. When you order the kit, you will receive new hoops and a set of instructions. Unfortunately, there are a couple of problems:

First, the kit is not complete, there are some additional parts required. The list of parts varies depending on the type of car you have (color and rear-console configuration).

Second, the instructions with the kit do not cover the install for a Harmon Kardon equipped vehicle.

This article seeks to address these shortcomings and to provide the potential hoop-installer with enough information to make the decision to install themselves or to have BMW do the job.

General Instructions

BMW will generally quote about 5 hours of time to do the install. Most BMW dealers charge around $75 per hour. A competent do-it-yourselfer should plan on about 8 to 10 hours. Although it’s not a technically complex procedure, there are lots of steps and some fabrication required. In general, anyone handy with a wrench and power drill can probably do it. The only “special” requirements are for the special tools required: TORX bits, metric torque wrench, Hex keys, dremal tool or power drill and screwdrivers.

Although your car can be driven during this procedure, it will likely have a lot of small parts loose, so it’s not advisable. Therefore you should plan ahead and have all the parts and tools ready beforehand.

Before you start, clean the rear window. Once the hoops are on it will be a lot harder to do so you want to do a really good job. In addition, have a couple of towels around to protect the window as you work. Generally speaking, the top is down for most of the install, so only a small part of the window is exposed.

As with all procedures read all the instructions first. Print these instructions beforehand. You’ll want them close by as you start to take your car apart. The hoop kit will come with instructions as well, but they will be in German with an English transation in the back. It’s much easier to follow these instructions in English (unless, of course, you speak German 😉

As you remove small parts, tape them to the instruction sheet or tape them near where they came from (whichever is easier for you). There are lots of different sizes and shapes and they are easily confused.

When you are done, sweep up before moving the car, that way you will not run over an errant screw and ruin a $200 tire.

BMW only wrote up instructions for cars with the “Storage Compartment” option. They did, however, provide parts for retrofit of HK subwoofer cars, but with no additional instructions. Since the majority of the instructions in this article come directly from the BMW english instructions shipped with the kit, they are intended for the “Storage Compartment” installation, but can generally be used with the HK subwoofer. I have added notes where the Harmon Kardon installation differs. These are identified by “HK NOTE:”. There are no instructions for the Nokia subwoofer and no one I have ever talked to has attempted to retrofit hoops to a Nokia-equipped car.

Parts

The part number for the main kit is 54-61-9-408-817. BMW list price is $640.00, but you can find them at a discounted cost of $430 from some internet-friendly BMW parts departments. You can also try your local BMW dealer who will generally give BMWCCA members a discount on parts (15 or 20%).

In addition to the kit you also need to order a replacement set of plastic covers for the rear storage/subwoofer area:

The actual part numbers will differ depending on the color of your interior and your rear compartment type (Storage or HK Sub). See the following table for the list of parts you’ll need to order in addition to the hoop kit:

Harmon Kardon Subwoofer Storage compartment

Beige interior

51-16-8-407-986 $59.41

51-43-8-407-167 $28.09

51-43-8-407-168 $28.09

51-43-8-407-173 $4.45

51-43-8-407-174 $4.45

65-10-8-407-995 $8.57

65-10-8-407-996 $8.57

Total: $141.63

51-16-8-407-179 $10.01

51-16-8-407-180 $10.01

51-16-8-407-239 $88.72

51-43-8-407-167 $28.09

51-43-8-407-168 $28.09

51-43-8-407-173 $4.45

51-43-8-407-174 $4.45

Total: $173.82

Black interior

51-16-8-407-985 $59.41

51-43-8-407-165 $28.09

51-43-8-407-166 $28.09

51-43-8-407-171 $4.45

51-43-8-407-172 $4.45

65-10-8-407-995 $8.57

65-10-8-407-996 $8.57

Total: $141.63

51-16-8-407-177 $10.01

51-16-8-407-178 $10.01

51-16-8-407-238 $88.72

51-43-8-407-165 $28.09

51-43-8-407-166 $28.09

51-43-8-407-171 $4.45

51-43-8-407-172 $4.45

Total: $173.82

The kit for the subwoofer will only work with the Harmon Kardon subwoofer. There is no kit available for Z3s with the “regular” Nokia subwoofer.

HK Note: If you’re doing HK, you’ll also need six 6×20 (6 mm x 1mm) pan-head screws which can be bought from Home Depot or your local hardware supply.

You may also want to order a number of small caps for the screw heads:

Black Screw Cap: 51 161 949 793

Beige Screw Cap: 51 168 398 920

You will be removing about 6 of them and will, more than likely, destroy most of them in the process.

You should also order a gasket: 51 168 399 072

This part fits in between the new rear covers. Although you do get one gasket with it, the extras will allow you to seal up the area between the covers.

Thre are two extra projects which are easy to perform as part of this install. For them you will need 4 size “00” washers, a small strip of velcro “loop-side” and a piece of foam padding approximately 12 x 12 inches large and 1/4 inch thick. These projects are not absolutely necessary to do for the hoop install, but since you will have the car apart, it’s a good time to do it.

Although it’s beyond the scope of this article, hoop-install is also a perfect time to replace your rear speakers.

54-61-9-408-817 Kit Contents

HK Note: You will need to modify part H. You can toss parts I and J – you won’t need them.

Extra Parts:

You should have the following “Extra parts”:

m. seatbelt tower covers (L & R)

n. inner covers (L & R)

o. center cover

p. brackets (2x)

q. gasket set

r. pan head screws (from Home Depot – HK only) (6x)

Tools

Note: In the instructions, the word “spanner” means “wrench”. The instructions were clearly written by Germans for the UK market.

You’ll also need a socket set (with philips screwdriver bits for hard to reach places) and a saw or a dremal tool if you are doing the HK install.

Important Safety Tip: When sticking tools down inside the car, be sure they are tightly attached. When I did this, in the final tightening of the hoops, I dropped a TORX attachment down into the opening and had to take the whole thing apart. Don’t let this happen to you. Suggestion: tape your tools together.

Phase I – Lay out your parts

Lay out a sheet or large towel and place all your parts on it. Take inventory and make sure you have everything:

Phase II – Strip Your Car Naked

In order to install the hoops, you will need to remove a large number of parts from the car. Before starting, lay down a sheet, or large towel where you will place the parts you remove. Be sure to label each part as you remove it, this will help when you go to put it back together.

Important Safety Tip: You will need to have the top folded down. The rear window will be exposed and will be very close to where you are working. You should take extra care to cover the window with a towel to protect it.

Note: Those darn screw covers! They are easy to tear. I’ve used a strong paper clip to remove them, but you are better off just buying a bunch before you start and not worrying about how badly you screw them up in the removal process. There is a small hole along the edge, you can grasp onto this hole and pull. Usually the cover just shreds at this point.

Note that you just gently lifting up the console enough to get at the screws. Be careful, it’s still attached at the front and you can damage it if you pull too much.

Hint: raise the roof at this point. It gives you a little more room to work in for the next step and there’s less danger of hurting the rear window as you remove the screws behind the storage box.

Now lower the roof.

HK Note: In order to gain access to the HK compartment, pull up on the cover, hard, from the front center area. It is hinged at the back and should just fold back. Don’t worry about breaking it – you’re just going to throw it away.

Next remove the grill for the HK “speaker”. You can do this by grasping the sides and pulling towards you. Remove your “snorkel” (this is the part which moves the sounds from the HK down to the grill) by pulling it outwards through the grill opening. Next, remove the HK subwoofer by unscrewing it from it’s mounts (4 screws) and unhooking it from the wiring harness. (for more information see this article from //MZ3.NET)

The instructions “Undo the clips(1) on the rear floor covering” refers to the plastic piece behind the seats. The diagram shows you looking from the drivers side towards the passenger seat belt. Unfortunately, in order to get this part to move as much as you need to, you also have to undo the sill strip at the bottom of the door. I just pulled up (HARD) and it came off. While you’re pulling it feels like you’re going to break it, but it’s pretty resilient. There’s probably a better way to do it. I suspect if you pull up and “reverse curl” the sil, the part will release from the fasteners. However on mine, 2 fasteners pulled out, still attached on both sides. This was not a big deal, I simply removed the third, and inserted it into the sil on reinstallation.

Phase III – Install the Hoops

OK, you now should have a naked car. The next step is to start installing the hoop supports and the hoops themselves.

HK Note: Before starting, attach your extra “HK part P” to “Part B” (see the parts list) with the screws you got from Home Depot. This bracket will support your HK subwoofer later on in the install.

HK Note: Skip this step, you don’t need the hinge

HK Note: Skip this step (F 36 54 059)- don’t remove the old silver “hinge supports” – you need them to back up the Tenax fasteners.

HK Note: you’ll need to “modify” the box which fits inside the console by cutting off the ends as indicated by the red line in picture. You don’t use the center box, but you will need the “ears” (the ends). Keep as much of the ends as will allow you to preserve the slots (these are used for the trim parts to secure with).

HK Note: Skip this step (F36 54 060). You will not need the hinges. Look at the next step, but skip down to the next HK Note instructions.

HK Note: Secure the side parts (highlighted in red in the picture) as indicated in the instructions. Next put the HK Subwoofer back in, reconnecting it to the wiring harness. The HK Cover does not use the hinges. Instead, it is secured by small tabs in the back. The new top will need to be inserted vertically. Before doing so, you must modify the metal plate (highlighted in yellow)

You’ll need to drill a couple new holes in the plate which secures the front of the cover. The problem is that the “studs” in the cover don’t line up the way the ones in the old cover do. I put some masking tape onto the cover and “pushed” an indentation into it to see where the holes should go. I then used my demal to make the holes. Careful: I made a mistake and made the holes a little too large, so I to buy a new part and start all over.

You also need to enlarge the existing holes to make room for some new screws on the cover where the old studs went. The new top then just “drops in”. You need to be careful to place it down vertically or you might break the small plastic parts which hold it on.

Phase IV Additional Hints and Tips

Now that you’ve taken most of the back console apart, you can take the opportunity to improve things a little more. There are two major areas in the rear console which can be improved with a little extra work:

– Eliminate the buzz from the HK subwoofer

– Improve the Tenax Fasteners (these are the little round knobby bits you fasten your boot cover to)

First wrap your subwoofer snorkel in some kind of foam insulation when you are reinstalling it. This prevents it from vibrating. I used some backing foam, but you can find this stuff at any harware store in the insulation section.

Next, get some velcro. You’ll just need the “fuzzy” (loop) side. Cut it into small (1/4 inch) strips. Look for wear-points on the inside of the grill. If you can’t find any, simply place the velcro near each corner. If you do find a wear point, place the velcro over it. This prevents the grill from buzzing.

While you’ve got the Tenax fasteners off, do the “Robert trick” – put a couple of “00 washers” behind them to stick them out more and make the boot easier to fasten.

Phase V Cleanup

Parts-is-parts… and if you did the HK install, you’ll have a bunch of extras:

Don’t worry about it. The HK install does not require these parts as they are designed to support the storage compartment install.

You did it!

Congratulations! You’ve now got a safer, cooler looking car.

Now that you’ve got rollhoops you can also avail yourself to another nice feature: The Wind Blocker. There are two versions available, a clear, plexiglas version from Z-Aids and a mesh version form BMW (Part # 82-15-9-408-546). This article from MZ3.net provides a pretty good comparison of the two products. I personally own both of them and enjoy using the clear screen in the spring and fall, reserving the mesh screen for the summer (because you can fold it down if you want the “wind through your hair” effect).

Overall, I’m very pleased with my rollhoops. Hope you are too!

AC Schnitzer Roll Hoops

Pros: Look Really Good, Easy to Install
Cons: Very Expensive
Cost: $1086 (list)

Comparing the Schnitzer polished stainless steel roll hoops to the stock BMW roll hoops the there are several differences. The most obvious difference is the chrome finish instead of the flat black rubberized finish. The Schnitzer hoops have a black pad on the top front of the hoops. And while the overall shape is nearly identical the profile of the Schnitzer hoops is round where the stock hoops have a arrow or triangle shaped profile.

On closer inspection there is one other difference that does affect the installation. The BMW hoops are held in place with three torx bolts. Where each of these bolts comes on contact with the stock roll hoops there is a shallow bored out indentation. The Schnitzer roll hoops do not have these. (Note: You can click on any of the pictures in this article to see a larger image).

When I started this project I was expecting a complicated installation procedure. I had installed an HMS roll bar on my previous 1.9 Z3 and while the installation went smoothly with the HMS roll bar, it took most of the day. I wasn’t expecting this installation to take all day, but I figured it would take at least a couple hours. To my surprise the installation was over before I knew it.

The only special tool you will need for this installation is a torx 40 driver. I had to start with a visit to the local hardware store. I had a set of torx heads for my cordless screw driver, but the largest one was a torx 30 (too small). In addition to the torx 40, I also used a phillips head and a flat blade screw driver.

Each roll hoop is held in place with three torx bolts (that act like set screws). The first step of the installation is to gain access to two of the set screws by removing the access panel at the base of the roll hoop. Use caution to make sure you don’t damage the plastic edges when you pop off the access panel.

Once the panel is removed you can see the two torx 40 bolts (I’m calling them set screws). Remove both of these but hold on to them because we will be reinstalling them later. These two torx bolts are shorter than the third bolt we will be removing in the next step so don’t mix them up.

Note: the pictures in this article show the removal of the drivers side roll hoop. You can duplicate the steps for the passenger side at the same or do the passenger side after the drivers side is complete.

The other set screw we need to remove is holding the inside of the roll hoop in place. To gain access to this bolt you will need to remove the HK subwoofer (or storage compartment). Rather than duplicate those instructions read the H&K Sub Dissected article.

Once the subwoofer is removed you will see the one remaining torx 40 bolt. Remove this bolt but hold on to it because we will be reinstalling it later.

Once the three torx 40 bolts are removed you can pull straight up on the roll hoop and it will slide out. There are rubber gaskets between the stock roll hoop and the plastic of the rear console. When I pulled the roll hoop out one of the plastic sections came loose because the gasket was stuck to it. Don’t be concerned if this happens to you, the plastic can be snapped back on.

Installing the Schnitzer roll hoop is the direct reverse of the steps we’ve done so far. The Schnitzer hoops come with their own rubber gaskets so make sure you have them on both the inner and the outer bars before sliding the new Schnitzer hoop down into place.

Earlier I told you that the Schnitzer hoops didn’t have the small indentations for the torx bolts. Because of this the torx bolts will not go back in as far as the stock bolts did. This initially concerned me so once I tightened the bolts to 22 nm (as the included instructions stated). I then removed the Schnitzer roll hoop and inspected it.

I was happy to see that each of the torx bolts had left slight indentations in the bar. So I was confident that the new Schnitzer roll hoops were just as secure as the old BMW ones.

Once I had one of the Schnitzer roll hoops installed I compared the two. The Schnitzer roll hoop appeared to lean slightly more forward than the BMW hoop (the picture at the right shows this). The two hoops appeared to be the same height, however it’s possible that the Schnitzer one was slightly taller.

I’m not sure what to think of the black pad on the front of the roll hoop. Visually it doesn’t do anything for me and I was considering removing it. But then there was a story on the message board about an individual that was driving a Z3 and during an accident hit his head on the BMW roll hoop. After reading that story I decided to leave the pad.

Right after installing the Schnitzer roll hoops I wondered if it was “too much”. But that thought faded as I continued staring at them. The ultimate test came when I asked my wife to come to the garage and give her opinion. She took a look at them and her first comment was “WOW”, and with that one word I knew I had done the right thing. I know the chrome look isn’t something that everybody is going to like, but I REALLY like it.

If there is a downside to these roll hoops, it is that I don’t want to cover them up with a wind screen. The BMW roll hoop wind screen still works with the Schnitzer hoops, but the pad on the front of the hoop stretches the material pretty tight. I’m okay with that but more importantly the BMW wind screen hides the chrome.

At the 1999 Z3 Homecoming I showed the Schnitzer roll hoops to JD (the maker of the clear windscreen). He measured the Schnitzer hoops and made a slightly modified version of his windscreen that works with the Schnitzer hoops. Turns out all he had to do was cut out a couple notches for the black pads since the Schnitzer hoops have the same curve, height and mounting points as the BMW hoops.

Used Airbags

I hope you never have to see your Z3 in this condition, but below are some pictures of a Z3 after its airbags had been deployed. I’m not sure whose Z3 this is; it was parked at a BMW dealership.

This first picture shows the passenger side airbag. It is much larger than I expected it to be. The fabric looks like a thick, almost canvas like surface.

The driver’s side airbag was much smaller, but it looked like someone has pushed part of the bag back into the steering wheel. Looking around the cabin, I expected to see some white powder, but the interior was clean.

What surprised me the most was how little damage there was to the front bumper. I expected to see a lot more damage if the impact was enough to set off the airbags. It is my understanding that the Z3 knows if you are wearing your seat belts or not and will deploy the airbags in a lesser impact if you are not wearing your seat belt. I don’t really know any details, just observing how little damage there was to the front bumper.

BMW Roll Hoops

Pros: Rollover protection, looks great
Cons: Hard to install
Cost: $570 / $602

If your BMW Z3 does not have rollhoops it may be possible to retrofit them into your vehicle. BMW has an upgrade kit that contains the hoops themselves however the hoops can only be retrofitted from into Z3s built on or after 1/97. Specifically 1.9 VIN LB83105 and later; 2.8 VIN LC01377 and later. No earlier production will work.

In addition to the kit you also need to order a replacement set of plastic covers for the rear storage/subwoofer area The cost of the main roll hoop kit is roughly $430 from competitive BMW parts departments that sell over the internet (BMW list price is $640.00). The part number for the main kit is 54-61-9-408-817. The cost of the replacement set of plastic covers varies depending on whether your interior is beige or black, and whether you have the storage compartment or Harmon Kardon subwoofer. See the table below for the additional parts you need and their price. These are the tower covers, side covers for towers, lid for box, small covers where bars go through the lid. With the subwoofer, you will have is the tower covers, side covers for towers, a new lid, and also two brackets and a new subwoofer box.

Please note that the kit for the subwoofer will only work on Z3s with the Harmon Kardon subwoofer. There is not a kit available for Z3s with the “regular” Nokia subwoofer.

Harmon Kardon Subwoofer Storage compartment

Beige interior

51-16-8-407-986 $59.41

51-43-8-407-167 $28.09

51-43-8-407-168 $28.09

51-43-8-407-173 $4.45

51-43-8-407-174 $4.45

65-10-8-407-995 $8.57

65-10-8-407-996 $8.57

Total: $141.63

51-16-8-407-179 $10.01

51-16-8-407-180 $10.01

51-16-8-407-239 $88.72

51-43-8-407-167 $28.09

51-43-8-407-168 $28.09

51-43-8-407-173 $4.45

51-43-8-407-174 $4.45

Total: $173.82

Black interior

51-16-8-407-985 $59.41

51-43-8-407-165 $28.09

51-43-8-407-166 $28.09

51-43-8-407-171 $4.45

51-43-8-407-172 $4.45

65-10-8-407-995 $8.57

65-10-8-407-996 $8.57

Total: $141.63

51-16-8-407-177 $10.01

51-16-8-407-178 $10.01

51-16-8-407-238 $88.72

51-43-8-407-165 $28.09

51-43-8-407-166 $28.09

51-43-8-407-171 $4.45

51-43-8-407-172 $4.45

Total: $173.82

HMS Rollbar

Pros: Rollover protection, aggressive look
Cons: Hard to install, occupies windscreen mounting location
Cost: $700

I had the pleasure of attending the 1997 Z3 Reunion. At this reunion I got to watch a video of Z3’s being crash tested. I was very impressed with Z3’s ability to protect the driver in an accident in all but one of the tests… the rollover.

I think my paranoia started there watching that video, but it was only a slight paranoia because I could tell myself “how would you ever roll a Z3”. Later I remembered a story I heard about six months before the reunion. A Z3 owner was rear ended by a pickup truck going about 40mph. The pickup smacked into the back of the Z3 and crunched it pretty good, but the truck didn’t stop when it hit the bumper. The truck’s bumper hit the Z3 at about mid-trunk and basically jumped up onto the trunk and eventually stopped about a foot and a half behind the drivers head. If the truck had been going any faster it might have driven right into the back of the driver’s head because there was nothing to stop it.

That was it, now my paranoia was real. I started noticing how many big pickups, and surburbans there were in Dallas and it was starting to really spook me every time one got behind me. Okay I’m exaggerating a little but my paranoia was real and it was taking away from the enjoyment of driving.

I have a 1997 Z3, starting with the 1998 models BMW added rollbars as a standard feature (well really they’re roll-hoops not rollbars but basically the same thing PROTECTION). As a ’97 owner I really only had one option and that was HMS Motorsport (Z3s built on or after 1/1/97 can get the rollhoops). The owner of HMS also owns a Z3, so he took the time and capital to design a rollbar specifically for the BMW Z3. The design is top notch with an emphasis on racing and safety.

Once I had the rollbar ordered and delivered I was left with the small task of installing it. Thankfully I had several friends who helped me do the installation (which really wasn’t nearly as difficult as I thought it would be).

So now my Z3 has rollbar installed and I am extremely pleased with it. I think it adds an aggressive look to Z3 and more importantly protects Robert from that evil suburban. I like the appearance but it does change the Z3’s looks quite a bit and some may not care for the more aggressive look.

Sold By:

HMS Motorsport

www.hms-motorsport.com

(888) HMS-3BMW