V8 engine sound

[shadowninja]

Anyone know why the Mercedes V8 sounds deeper than say a Rover or Chevrolet V8?

 

[whitenemesis]

Gotta be the exhaust design......

 

[jibcl500]

Im using my CL500 at the moment, havent driving it in over a month and now we down to 4 Mercs and Beetle Im using my CL as an everyday motor for now and I dont remember MY CL sounding so good, then later I watched as a RR 4.6 cruised past and I thought that sounded better.

MB dont want thier V8's sounding good thats what AMG are for.

jib

 

[BlackC55]

Intake and exhaust design are the main factors in the "noise".

 

[wireman]

It is possible that the engines crank shaft is different, some V8 enginges (Rolls) use a four throw flat crank with shared journals at 180 deg others (american) use a 90 deg angle with eight throws. The firing order of each bank differs in each type and they will have a very different sound to each other. The 90 degree crank is better for high power whilst the 180 deg is smoother in terms of engine vibrations since this is only in the vertical plane.

 

[angus falconer]

A lot of it is in the exhaust. Recent AMG seem to be much louder out the back than before. If you hear recent Audi RS4's and RS6's drive by there's a real rumble from the exhaust. IThis is mainly down to the cats and solinecer boxes specified. f I replaced my cats with straight through pipes I'd get that level of noise. Many manufacturers smother exhaust (and intake) noise to almost nothing. If you hear a Lexus 430 go by you can barely hear anything, let alone the fact that its got a big V8.

 

[Myros]

I think our 500 SL

sounds fantastic. At idle it throbs like lion that's purring after a dinner of particularly tasty gazelle, and at higher revs, it sounds really purposeful and powerful, without being noisy in an annoying fat boy exhaust kind of way.
It must help not having a cat though.
and it does some lovely spits and pops on over-run coming down a mountain.

 

[stats007]

Exhaust has little to do with it actually. The differences between a Rover V8 / Ferrari V8 / TVR (AJP) V8 and Merc V8 are all down to crank / timing design, V-angle and the firing order.

You can tune the sound by changing the exhaust but you won't be able to affect the inherent nature of the engine.

 

[shadowninja]

Thanks for the replies. I replaced the standard (rusting!) AMG exhaust with something that looks the same but only has a backbox (plus very AMG-looking tips). It sounds only slightly louder than standard at idle. There is a slight wum-wum noise (which isn't audible with the standard exhaust). On acceleration, at low revs, it sounds like I've accidentally caught a lion's tail in the boot: a deep bellowing, throbbing noise. At higher revs, it opened up and sounded more angry/sporty.

Comparing this to a TVR Chimaera which also has one silencer box as standard, the Chimaera is much louder. What was interesting was that without any box on the AMG and just the cats, it still sounded slightly muffled at idle, whilst it barked angrily when revved. A Chimaera with straight-through pipes and two cats sounds much more angry even at idle - think old school V8.

I know it isn't important, but it's just interesting to see the differences esp as the sound is part of the fun of ownership of a V8.

 

[shadowninja]

You can tune the sound by changing the exhaust but you won't be able to affect the inherent nature of the engine.

I want to know what an SLR sounds like at idle and at high revs, now. Actually, now that I say that, I saw one at the Tolworth roundabout last month. Was about 5 cars away and couldn't hear a thing. It is nice knowing that I have a very similar engine to the one used in an SLR anyway.

 

[stats007]

There's very little that's common between your engine and an SLR's!

 

[television]

Its all to do with resonance beat and harmonics, almost the same as an organ

 

[dava]

Intake and exhaust design are the main factors in the "noise".

I agree with above. MB made a SLK280 sport and they made a special airfilter to give it a 'sporty' sound.

 

[stats007]

All you'll get from a change in airfilter is a difference in induction noise.

 

[television]

All you'll get from a change in airfilter is a difference in induction noise.

As on the K & N filters, not for me

 

[shadowninja]

There's very little that's common between your engine and an SLR's!

they do sound similar though, from what I've heard. And isn't the SLR based on the normal AMG 5.5 litre V8?

 

[stats007]

Not really - the M155 might be a 5.5 litre V8 but it's completely bespoke in components.

The supercharger and side exit exhausts contribute to the SLRs exclusive sound.

 

[shadowninja]

oh ok. different design?

 

[television]

If it was not for the heat, you could send the exhaust through a reed organ pipe say about 60hz-70hz

 

[wireman]

Why not use a metal reed Malcolm? There are steam organs and burning gas organs built as novel and excting new ventures in their time, about 100 years ago. Also note that you dont find a reed in all organ pipes, some of them are whistles.

I myself prefer a silent aproach it attracts much less attention.