Prior to installing the Supersprint exhaust, three "before" or baseline dyno tests were preformed. The results of those test will be compared to the results from the "after" dyno tests in the next part of this article. But for now let me explain the installation process that took place between the before and after dyno tests.

The keen eye will notice that the pictures on this page are from two different vehicles. Prior to my installation, another Z3 owner had installed a Supersprint exhaust on his Z3 and Robert was there to take pictures of that installation as well. The only difference between the two Supersprint exhausts were the type of exhaust tips. Chris got the straight tips and I got the turned up or DTM style tips. Since the type of tips on the end of the exhaust have very little impact on installation the two sets of pictures could be used together.

The first step was to remove the stock exhaust, problem was we had just completed the first set of dyno tests so the stock exhaust was hot. After the stock exhaust cooled down to a point where we were able to hold it (15 minutes) we were able to remove it.

The exhaust is held in place in four places (pictures below). The first (front most) connection is where the exhaust bolts onto the flange of the catalytic converter via two 2 13mm nuts and bolts. The middle connection is actually just a safety/backup connection, but it uses a rubber belt (attached to the vehicle) around an additional bracket (attached to the exhaust) to catch the exhaust if the rear mounts fail.

Towards the rear bumper, two additional rubber rings support and attach the rear of the exhaust to the vehicle. In order to remove them we sprayed the rubber muffler hangers with lubricant and then popped them loose using a pry-bar. The actual order we used in removing the exhaust was to loosen the front bolts, unbolt/remove the middle bracket. Then with someone holding the front of the exhaust, the rear connections were worked loose. With a person holding either end the removal was easily accomplished, however it would have been rather difficult with only one person. trying to juggle both ends.

After removing the stock exhaust it was time to unpack the Supersprint exhaust. I purchased this exhaust from BMP, it came very well packaged, the entire exhaust was wrapped in thick shrink wrap with additional padding covering the exhaust tips. Not sure if this is something BMP does or if all Supersprint exhausts come this way. The packaging provided a very effective protective layer over the exhaust, however the shrink-wrap was so tight one of the support brackets was bent. We didn't realize this at the time, but later it was easy to fix by just bending the support back to its normal position, the catch of course being that you won't know what the "normal" position is until you've got the exhaust installed and you're trying to put the rubber hangers on.

There is one important part I should point out, you better get a friend to carry the new and old exhaust for you. The exhaust is rather large and does not fit in the trunk (not even close). You could carry the new exhaust up front with you but the used/stock exhaust will be very dirty. For this installation Nancy carried my exhaust along with Alan's two exhausts in her SUV. Once the stock exhausts were removed we wrapped them in trash bags and duct tape for the drive home.

Comparing the stock and Supersprint exhaust side by side was interesting. The Supersprint exhaust looked quite handsome with its black-crackle finish and polished stainless steel tips. It also looked much more svelte and linear than the stock exhaust. The stock exhaust had 4 diameter changes in just the piping alone. The resonator and the garbage-can-sized muffler looked like something off of a truck when compared with the Supersprint. There was a brief moment where I thought BMP had shipped me the wrong exhaust. The muffler part of the exhaust was smaller so the rear support arms were longer (to make up the difference). But what concerned me was how much different the connection from the catalytic converter to the muffler was. The Supersprint still had the crimp in the exhaust but the path seemed much straighter. However my concerns of receiving the wrong exhaust were removed when we stacked the two exhausts on top of each other and noticed the mounting locations were the same.

Mounting the new exhaust was a definite two-man job. The "safety hanger" was reinserted into the rubber hanger/bracket, and the flange-end of the exhaust was fitted to the catalytic converter, loosely fitting the nuts. We then re-popped the muffler hangers on to the Supersprint, and VOILA!, it didn't fit. We stepped back to analyze the situation and found immediately that the hanger brackets on the Supersprint had been bent somewhere along its route from Italy to Texas. Using the biggest pair of channel-locks we could find, we adjusted the brackets to proper alignment, and VOILA!, it still didn't fit.

We has been warned by other Z3 exhaust upgraders that the tight fit of the exhaust tail pipes had previously led to some bumper trim scarring/melting. Because of this warning we were paying very close attention to how the tips fit in the cutout. Ahead of time we were warned that the exhaust tips will move towards the drivers side of the cutout when the exhaust gets hot and back towards the passenger side when it cools back down. So our goal was to get the exhaust tips to hang towards the passenger side of the cutout as much as possible (exhaust was cold as we were mounting it).

The problem we ran into was after installing the exhaust we noticed the tips were already off center towards the drivers side. We knew that this was going to be a problem because once the exhaust got hot it would push even further towards the drivers side and probably scar/melt the bumper trim. Further analysis indicated that the "safety hanger" on the Supersprint was too far to the passenger side of the car. After inspecting how the bracket worked we determined that the sides of the bracket serve very little purpose because the support loop uses the top of the bracket. We were also told that this bracket is just a backup bracket in case the rear ones fail.

For a brief moment we considered removing it all together, but then we thought of a better plan. We decided to modify the safety bracket, since it appeared cheaper to replace than the exhaust if we screwed it up (Supersprint has been informed of the problem and is investigating a solution). The bracket pictured to the left is after the modification (compare it to one of the pictures at the top of this page and you will noticed the removed metal). The fine folks at Alamo ground off one side of the bracket, and after we re-installed everything the exhaust was no longer being pushed against the drivers side of the rear bumper apron.

All that remained was to fine-tune placement of the tips within the rear bumper apron. This was accomplished using the aforementioned massive channel-lock pliers to tweak the muffler hanger brackets. We aligned the exhaust to "dress to the right" when cold, as 2.8 Supersprint exhausts are known to shift left about one-half inch at operating temperatures. It looked fantastic.

Update: Supersprint is modifying all current and future 2.8 Z3 exhaust systems to correct for the safety bracket misalignment. Supersprint is also adding side-to-side adjustable hangers to allow for precise fitting of the exhaust tips in the cutout.

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