[mobiousblack]

So current owners, we all know that switching between normal, sport, and track changes the intensity of the sound you hear inside the car (outside sound always stays the same apparently). Anyways my friend is in talks with a company who is making mufflers and stuff of the sorts for the MP4, and the company mentioned how difficult it is because of that valved system and that ECU programming is required.

Now here is the part that interested me, the guy who is in contact with my friend stated that the valve systems is being discontinued. Now I love having the option to switch between the sound I hear when I am driving, I love the loudness of track (not something I want on 24/7 though but having the option there is awesome), and I love how quite it gets on normal for a normal drive.

So if this is true, that means new owners won't get the choice to switch between sounds, and its obvious that they won't keep it at track levels because thats just too loud for 24/7 usage. So if this is true I think it might be something similar to sports mode, which is a downer for new owners cause the car sounds like a beast on track. What do you guys think about this?

 

[Senna]

Are you talking about the intake generated sound for the cabin or the valves in the exhaust system ?

 

[mobiousblack]

Are you talking about the intake generated sound for the cabin or the valves in the exhaust system ?

I thought the valves are responsible for the sound in the cabin, that's what their scrapping apparently. What are the valves responsible for then?

 

[roundincircles]

I thought the valves are responsible for the sound in the cabin, that's what their scrapping apparently. What are the valves responsible for then?

Mobiousblack. I think there is some confusion about the word valve?

The cabin noise induction is caused by a rubber diaphragm vibrating and thus causing sound-waves to pass into the cabin. A valve is switched to expose the diaphragm to exhaust vibration and thus allow transfer into the cabin or the valve is closed to stop the noise.

At the recent feedback sessions in MPC/MTC they acknowledged it was a false noise which received criticism but they did not confirm there plans for change.

I have had the induction system disconnected even though I have an 80dB hearing loss. I found it painful at full 'welly' or 'chat'. You younger guys have higher thresholds of pain

 

[Moncho]

I've never been a fan of the induction noise into the cabin. I find it artificial and annoying. I've actually considered having it disabled by the dealer. It seems to go against Mclaren's "form follows function" credo.
A "true" valved exhaust for exterior noise, however, is something I would definitely consider.

 

[mobiousblack]

Thanks for clarifying all this guys, you learn something every day

 

[roundincircles]

Mobiousblack. Do you ever drive the Aston now you have the MAC?

What do you enjoy about the Aston? I had a day on track at Silverstone as a guest of Aston and was very impressed by the all day thrash-ability/reliability plus the sense of achievement driving a 'traditional' sports car (V12 Vantage).

 

[mobiousblack]

Mobiousblack. Do you ever drive the Aston now you have the MAC?

What do you enjoy about the Aston? I had a day on track at Silverstone as a guest of Aston and was very impressed by the all day thrash-ability/reliability plus the sense of achievement driving a 'traditional' sports car (V12 Vantage).

I do from time to time, its definitely a different ride, more sluggish, but the engine feels so powerful, feels less tampered with you know? Like the MP4's engine is amazing, but with so many bells and whistles to make it so, while engines in the SLS and DBS are completley different.

 

[texas mongrel]

How many guys would be interested in an aftermarket exhaust that featured cockpit-operated cut-outs to allow outside sound to be increased via a switch (similar to Vettes etc) I know someone who is interested in doing something like this. He's a well-known fabricator in the USA (and outside) so they would be good quality.

 

[[email protected]]

Hey guys, its Alex from Fabspeed here. Hope your all enjoying cars and hopefully are starting to think about doing performance upgrades on the Twin Turbo V8 engine. If your thinking about changing the exhaust system on your 12C, we have just the exhaust to wake up the power and sound. We have a few different options which consist of just changing the rear muffler or also adding our High Flow Sport Catalytic Converters for even more power and sound. We also offer straight through catalytic converter delete pipes if you are looking for maximum power. Here are some of the HP numbers of our different exhaust options below.

1) Stock MP4-12C HP: 571HP/477 TQ at the Wheels
2) Fabspeed X Pipe Supersport Muffler Only Upgrade: +6HP/12 TQ at the wheels.
3) Fabspeed X Pipe Supersport Muffler and 200 Cell Sport Cats: +28HP/29 TQ at the wheels.
4) Fabspeed Catalytic Converter Bypass/Delete Pipes with Stock Muffler: +33HP/28 TQ at the wheels.
5) Fabspeed Catalytic Converter Bypass/Delete Pipes with X Pipe Supersport Muffler: +39HP/40 TQ at the wheels.

Our direct bolt on X Pipe Supersport Muffler which flows better then Factory H pipe Sport option exhaust and it gives it a more deeper and unique sound. In addition to gaining another 6 HP and 12 Ft-Lbs. of Torque at the wheels. The exhaust is a direct replacement for the stock muffler on the car and takes about 4 hours to install.

You have the option of reusing your stock tips or go to our Dual style tips which are available in a high polish finish or black. This system has been tested and dyno proven to make power, sound more aggressive and have no effect on warranty or emissions. We have been working with a few McLaren Dealers to guarantee and approve the quality of our products on their customer cars. PM me if you have any questions or for special member pricing for any of the items.
Thanks,

Fabspeed McLaren MP-12C Exhaust Video: http://www.youtube.com/watch?v=VtZEl9s-wqI
Visit www.Fabspeed.com for Photos, Dyno Results and Videos.

 

[RC33]

Exhaust Valves flaps

Hi all,
Since we are on the topic of valves here, I took a picture from the tail end of the Optional sports exhaust and noticed the valves flaps.
Maybe I have not observed it properly since the exhaust system is so well hidden, I did not notice any actuators that operate the valves like those in the Ferrari, how and when does the valves open/close?

 

[douglasng]

So current owners, we all know that switching between normal, sport, and track changes the intensity of the sound you hear inside the car (outside sound always stays the same apparently). Anyways my friend is in talks with a company who is making mufflers and stuff of the sorts for the MP4, and the company mentioned how difficult it is because of that valved system and that ECU programming is required.

Now here is the part that interested me, the guy who is in contact with my friend stated that the valve systems is being discontinued. Now I love having the option to switch between the sound I hear when I am driving, I love the loudness of track (not something I want on 24/7 though but having the option there is awesome), and I love how quite it gets on normal for a normal drive.

So if this is true, that means new owners won't get the choice to switch between sounds, and its obvious that they won't keep it at track levels because thats just too loud for 24/7 usage. So if this is true I think it might be something similar to sports mode, which is a downer for new owners cause the car sounds like a beast on track. What do you guys think about this?

Yes this is true for MY13 cars, be it whether specced with standard or inconel sports exhaust. I doubt there is much difference in external sound, except for louder in-cabin noise due to ISG.

Mine is among the first batch of cars to utilize the valved exhaust system. Note that the valves were only available on the inconel sports exhaust. Standard exhaust did not come with valves. The valves on the inconel exhaust were linked to the car's ecu, which meant that I cannot unplug the valves permanently or risk triggering an electrical fault in the system.

 

[Ramy]

I'll post this here since it's a live exhaust thread.

Does anyone know the decibel readings of stock vs. inconel?

 

[RC33]

Valves in Optional Inconel Sports Exhaust?

Very interesting evaluation made by Duncati from the other thread http://www.mclarenlife.com/forums/mclaren-mp4-12c/1889-real-world-weight-4.html, I thought I should post it here as well since it relates to valved exhaust systems

Seeing mention of the exhaust weight difference, I thought I would just confirm that I have retrofitted a current specification (non-valved) Inconel exhaust to my Coupe and weighed both exhausts at the time of doing the change over.

The standard exhaust was 6.8 Kg and the Inconel sports exhaust was 4.4 Kg - so I can confirm there is a 2.4 Kg weight reduction between these specs.

Note that early Inconel sports exhausts had valve arrangement which has now been deleted from the current design since late 2012, so these may be marginally heavier than the 4.4 Kg of the current sports exhaust.

Thanks to Duncati we can now ascertain that the Optional inconel sports exhaust has marginal weight differences as compared with the aftermarket options.

Does it imply that the cars optioned with the Optional sports exhaust in late '12 would appear to be 'louder' since it does not come equipped with the valves?

 

[Duncati]

Hmm.... there seems to be some contradiction between what I have been advised and what seems to have been stated by douglasng - but I am pretty certain the following is correct:

- The standard exhaust has never had any internal valves.

- The early Inconel exhausts were fitted with internal valves to control noise at certain revs.

- The current Inconel exhausts have no internal valves and the earlier Inconel Sports Exhaust is now a discontinued part.

As far as I can see there is little, if any, visible difference between the design of the two Sports Exhaust - other than where the valves themselves were located.

I understand that McLaren found in the end it was just not necessary to use the valve arrangement to meet exhaust noise regulations (in the UK at least).

(This does raise the issue that I assume it may be possible that some overseas markets may still need and continue to be supplied with the valved Sports Exhaust due to tighter noise regulations, but I am only speculating on this.)

As far as I can tell from my car, I would say the non-valved system may be marginally louder at and around idle, but little or no different to the earlier Sports Exhaust once on the move.

I think we need to careful about the weight reduction claims by some of the after market exhaust manufacturers and how they relate to the above. Clearly I am only reporting the weight difference of the 'cat-back' rear exhaust (which is the only part difference between the McLaren 'Sports' and 'Standard' exhaust arrangements), but further weight could be saved earlier in the exhaust system and in the two stage cats.

However, I am always amused to see claims like an 10 Kg weight saving over standard by some aftermarket manufacturers when this only appears to relate to a rear box change - as it is obviously a bit tricky to achieve a greater weight saving than the standard system actually weighed in the first place!!!

 

[RC33]

I think we need to careful about the weight reduction claims by some of the after market exhaust manufacturers and how they relate to the above. Clearly I am only reporting the weight difference of the 'cat-back' rear exhaust (which is the only part difference between the McLaren 'Sports' and 'Standard' exhaust arrangements), but further weight could be saved earlier in the exhaust system and in the two stage cats.

However, I am always amused to see claims like an 10 Kg weight saving over standard by some aftermarket manufacturers when this only appears to relate to a rear box change - as it is obviously a bit tricky to achieve a greater weight saving than the standard system actually weighed in the first place!!!

As posted in http://www.mclarenlife.com/forums/mclaren-mp4-12c/2091-catalytic-converters-12c.html

and with reference to the weights gathered in this link http://www.lambopower.com/forum/index.php?showtopic=66813. The test weigh the standard exhaust at 7.5kg!!

Totally agreed with you on the weight saving or projection claims.

The Optional Inconel sports exhaust at just over 4 kg from the cat back is pretty light as compared to the aftermarket versions.

FWIW, the construction is basically just pipes, how much lighter can it really honestly become?

Only an upgrade from the Standard factory muffler is significant in weight and noise levels

 

[RC33]

Hmm.... there seems to be some contradiction between what I have been advised and what seems to have been stated by douglasng - but I am pretty certain the following is correct:

- The standard exhaust has never had any internal valves.

- The early Inconel exhausts were fitted with internal valves to control noise at certain revs.

- The current Inconel exhausts have no internal valves and the earlier Inconel Sports Exhaust is now a discontinued part.

As far as I can see there is little, if any, visible difference between the design of the two Sports Exhaust - other than where the valves themselves were located.

I understand that McLaren found in the end it was just not necessary to use the valve arrangement to meet exhaust noise regulations (in the UK at least).

(This does raise the issue that I assume it may be possible that some overseas markets may still need and continue to be supplied with the valved Sports Exhaust due to tighter noise regulations, but I am only speculating on this.)

As far as I can tell from my car, I would say the non-valved system may be marginally louder at and around idle, but little or no different to the earlier Sports Exhaust once on the move.

I just took a picture from the exhaust outlet of my car and found that the Optional Inconel Sports exhaust does not have a valve.

My car is a late 2012 model.

 

[brotherharry]

I'll post this here since it's a live exhaust thread.

Does anyone know the decibel readings of stock vs. inconel?

I was informed by McLaren Birmingham that
"Sports Exhaust is 102db stationary at 3750 rpm
Drive by 73.7db but it doesn’t say in what circumstance on the certificate of conformity"

The Bedford Autodrome (UK track day circuit with fairly agressive noise limits) told me that
"We have had two McLaren MP4-12C on track days they measure around 102.4db on static (fail) on drive by as long as all sports buttons etc are left turned off and dependent of driving style they measure around the 84 to 86db range, so are good to go but they do have to be driven with the noise issue taken into account."

I'd say standard exhaust will be a few db below those figures.

Oh, and while we're here and perving up the back of our car's rear ends, herewith my valveless stealth sports exhaust, from June 2012.