As we all know, there are a lot of exhaust options for the E60 M5. These can range from custom setups, Mufflers, Cat-Back exhausts, or any combination of each. The pricepoints also vary dramatically, some setups tipping the scales in the $3000 range for that lusted after V10 scream. This is a review of yet another type of exhaust modification, one that has been around since the days of rat-rodding with a modern twist: Electronic control for on-the-fly sound control.
For me, the benefits of an exhaust cutout are:
With the QTP setup, I now have a kit that is controlled from the cabin via 12v ship's power, protected by a 20-AMP fuse. I can at any point go completely back to stock, and re-utilize the QTP kit on any future cars (with the same 2.5" exhaust system - fairly common) The only "damage" done to the car was, obviously cutting the exhaust pipes (reversible, and with zero welds) and drilling of a Blank located behind the center console. That's it. Super non-intrusive.
Enough blab, on to the pics:
The kit is a very solid, well made unit. This is revision 2, which includes beefier components and more steel in the design. The exterior cannon plug connections *could* have been made better. They are all weather, but I wrapped them in electrical tape just in case. I over-engineer things. The kit is fine as-is...
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Installed, with large high-quality clamps. Don't use cheap crap. Do it right. I did not want to weld onto my exhaust, or the QTP apparatus. This way, you have a fully reversible, fully reusable (ebay-able?) kit that is completely DIY (if you don't suck).
They mount up here, with adequate (not ample) room for components and wiring. Harness was routed into the trunk via the existing pass-through used for brake pad sensor and wheel speed sensor wires, located on the passenger side rear wheel well behind the fender lining.
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Testing for operation before install. Open to close in under 5 seconds, and vice versa.
Sawzall action:
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Switch location:
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So, on to the review.
Lets start with the cons. As expected, I love the ability to control the sound. What I didn't expect was the level of in-cabin drone that exists when driving normally (ie, revs below 3K rpm and highway cruising). Man, I'm glad I can quiet this thing down at the flick of a switch. The dumps are far louder in-cabin than a muffler delete would be (I had a muffler delete on my E39 M5). This is due to the fact of WHERE the exhaust sound is jettisoned from the engine. With dump valves, the magic happens right at the rear wheel wells - where as with a muffler delete, the cannons are still pointed aft of the car. The nature of the V10 is such that it simply sounds Civic-like below 3k rpm. Obviously, I don't have to illustrate how unbelievably intoxicating this car sounds with dumps open while giving her a good flogging.
Also, this isn't a "fire and forget it" type of weapon... you are expected to conduct monthly maintenance to inspect tightness of the screws that hold the mechanism together and clean out any carbon buildup that may exist. Lubrication such as Liquid Wrench is also recommended of the valve and shaft assembly. In a snowy climate, it is a good idea to remove the valves completely during winter months. This isn't really a headache for me as a DIY-er, but if you paid a shop to install this is something to consider.
As for the benefits, they far outweigh the negatives:
This cost me less than $500. I did it alone, on my back, in my garage and it was fun (that sounded dirty). The lack of welds means a lack of paying someone to do this and get your exhausts crooked in the process (more muffler-delete experience). I already adjusted the length of muffler exiting the car (ie, how far it sticks out) once, because it looked slightly off from stock my first go around. With welds, you are stuck with what you got. The band clamps I used are excellent, absorbing any slight kinks in the exhaust, so don't worry about having leaks if your cut piece isn't 100% without small bends. Plus, at this point pre-muffler a leak wouldn't be detrimental to performance anyways. But they seal up very well and are highly recommended.
This looks and sounds totally stock, until you want to make noise. With them open, it is definitely not wife friendly, but your girlfriend may like it. Your neighbors will still like you, because you can quiet down the system as you enter or exit your block. With them open, trust me, the car will be louder than your mother last night. Closed, and everything returns to normalcy. This epitomizes the E60 M5. Adaptability. Control. It's the last piece of the puzzle that should have been installed from the factory (like sport mode on Maserati products).
I am thinking if I can get them to exit more towards the side of the car, like traditional side pipes would, that the sound while open would be much improved. I would also invest in some higher quality all weather cannon plugs for the external connections if you will be removing them often. The kit does come with blocker plates to install during the winter to keep everything fresh and clean. I'll keep everyone posted if I revise the kit, time permitting.
Hope the review helps. I have omitted the sound because there are already enough clips on YouTube including one guy who gets yelled at to come to dinner while videoing (lol) and another hoon that revs the heck out of his ice cold motor. If someone would tell me how to link youtube vids, I'll post those up...
For me, the benefits of an exhaust cutout are:
- Cost - my setup, as installed and everything pictured ran me under $500
- Ability to still look stock
- Ability to still sound stock when desired
- Ability to muffler-delete at will
- Ease of installation, DIY-ability, and ease of reversion back to stock when desired.
With the QTP setup, I now have a kit that is controlled from the cabin via 12v ship's power, protected by a 20-AMP fuse. I can at any point go completely back to stock, and re-utilize the QTP kit on any future cars (with the same 2.5" exhaust system - fairly common) The only "damage" done to the car was, obviously cutting the exhaust pipes (reversible, and with zero welds) and drilling of a Blank located behind the center console. That's it. Super non-intrusive.
Enough blab, on to the pics:
The kit is a very solid, well made unit. This is revision 2, which includes beefier components and more steel in the design. The exterior cannon plug connections *could* have been made better. They are all weather, but I wrapped them in electrical tape just in case. I over-engineer things. The kit is fine as-is...
Installed, with large high-quality clamps. Don't use cheap crap. Do it right. I did not want to weld onto my exhaust, or the QTP apparatus. This way, you have a fully reversible, fully reusable (ebay-able?) kit that is completely DIY (if you don't suck).
They mount up here, with adequate (not ample) room for components and wiring. Harness was routed into the trunk via the existing pass-through used for brake pad sensor and wheel speed sensor wires, located on the passenger side rear wheel well behind the fender lining.
Testing for operation before install. Open to close in under 5 seconds, and vice versa.
Sawzall action:
Switch location:
So, on to the review.
Lets start with the cons. As expected, I love the ability to control the sound. What I didn't expect was the level of in-cabin drone that exists when driving normally (ie, revs below 3K rpm and highway cruising). Man, I'm glad I can quiet this thing down at the flick of a switch. The dumps are far louder in-cabin than a muffler delete would be (I had a muffler delete on my E39 M5). This is due to the fact of WHERE the exhaust sound is jettisoned from the engine. With dump valves, the magic happens right at the rear wheel wells - where as with a muffler delete, the cannons are still pointed aft of the car. The nature of the V10 is such that it simply sounds Civic-like below 3k rpm. Obviously, I don't have to illustrate how unbelievably intoxicating this car sounds with dumps open while giving her a good flogging.
Also, this isn't a "fire and forget it" type of weapon... you are expected to conduct monthly maintenance to inspect tightness of the screws that hold the mechanism together and clean out any carbon buildup that may exist. Lubrication such as Liquid Wrench is also recommended of the valve and shaft assembly. In a snowy climate, it is a good idea to remove the valves completely during winter months. This isn't really a headache for me as a DIY-er, but if you paid a shop to install this is something to consider.
As for the benefits, they far outweigh the negatives:
This cost me less than $500. I did it alone, on my back, in my garage and it was fun (that sounded dirty). The lack of welds means a lack of paying someone to do this and get your exhausts crooked in the process (more muffler-delete experience). I already adjusted the length of muffler exiting the car (ie, how far it sticks out) once, because it looked slightly off from stock my first go around. With welds, you are stuck with what you got. The band clamps I used are excellent, absorbing any slight kinks in the exhaust, so don't worry about having leaks if your cut piece isn't 100% without small bends. Plus, at this point pre-muffler a leak wouldn't be detrimental to performance anyways. But they seal up very well and are highly recommended.
This looks and sounds totally stock, until you want to make noise. With them open, it is definitely not wife friendly, but your girlfriend may like it. Your neighbors will still like you, because you can quiet down the system as you enter or exit your block. With them open, trust me, the car will be louder than your mother last night. Closed, and everything returns to normalcy. This epitomizes the E60 M5. Adaptability. Control. It's the last piece of the puzzle that should have been installed from the factory (like sport mode on Maserati products).
I am thinking if I can get them to exit more towards the side of the car, like traditional side pipes would, that the sound while open would be much improved. I would also invest in some higher quality all weather cannon plugs for the external connections if you will be removing them often. The kit does come with blocker plates to install during the winter to keep everything fresh and clean. I'll keep everyone posted if I revise the kit, time permitting.
Hope the review helps. I have omitted the sound because there are already enough clips on YouTube including one guy who gets yelled at to come to dinner while videoing (lol) and another hoon that revs the heck out of his ice cold motor. If someone would tell me how to link youtube vids, I'll post those up...
I am so impatient when it comes to mods ha
