Who really knows what gives V8s their throaty exhaust note?

[Eli]

:Q

 

[Zenmervolt]

Originally posted by: CFster
CART engines are 2.65 liter turbo V8's that rev to 12K. They make around 750hp. (They used to rev to almost 17K)

IRL engines are 3.5 liter naturally aspirated V8's that rev to 10.5K. They make around 675hp.

F1 engines are 3.5 liter naturally aspirated V10's that rev to 19K. They make around 900hp.

All sound very different and unlike anything else in the world.

Well, the main reason that CART and IRL V8 engines sound different is the turbocharger's muffling effect on the CART cars' exaust.

ZV

 

Well I assume no one is going to answer my question, so, here's the answer ..........

I'm not going to tell you, HA-HA


The noise is from the exhaust gasses breaking the speed of sound, what you are in fact hearing are mini sonic booms.

 

[Zenmervolt]

Originally posted by: Roger
Well I assume no one is going to answer my question, so, here's the answer ..........

I'm not going to tell you, HA-HA


The noise is from the exhaust gasses breaking the speed of sound, what you are in fact hearing are mini sonic booms.

Now that's just plain cool.

ZV

 

[geno]

Originally posted by: MercenaryForHire
*insert sound of Ferrari 360 hitting 7K here*

*drools*

- M4H

that's a flat-plane crank V8, the sound shares little with that of cross-plane crank of American V8's

 

[Bulk Beef]

Originally posted by: godmare

Originally posted by: Eli
A 2L V8 would be cool.

Especially if it had an 8000RPM redline...

Ferrari used a 2l v12 in whatever roadster back in the day...

Moto Guzzi V8

500cc Gran Prix racer from the 50s

 

[Eli]

Originally posted by: sward666

Originally posted by: godmare

Originally posted by: Eli
A 2L V8 would be cool.

Especially if it had an 8000RPM redline...

Ferrari used a 2l v12 in whatever roadster back in the day...

Moto Guzzi V8

500cc Gran Prix racer from the 50s

Schweeeeeet.

 

[Ornery]

Originally posted by: geno

Originally posted by: MercenaryForHire
*insert sound of Ferrari 360 hitting 7K here*

*drools*

- M4H

that's a flat-plane crank V8, the sound shares little with that of cross-plane crank of American V8's

3.6-Liter, 90-Degree V8, 40-Valve, Twin DOHC

It's the displacement that makes the American V8s more 'throaty', not the cross-plane VS flat-plane configuration. I'd MUCH rather have low end grunt of a large displacement, than the buzzy, hyper power of a little screamer. There's no exhaust tip in the world that will compensate!

 

[Zenmervolt]

Originally posted by: Ornery

Originally posted by: geno

Originally posted by: MercenaryForHire
*insert sound of Ferrari 360 hitting 7K here*

*drools*

- M4H

that's a flat-plane crank V8, the sound shares little with that of cross-plane crank of American V8's

3.6-Liter, 90-Degree V8, 40-Valve, Twin DOHC

It's the displacement that makes the American V8s more 'throaty', not the cross-plane VS flat-plane configuration. I'd MUCH rather have low end grunt of a large displacement, than the buzzy, hyper power of a little screamer. There's no exhaust tip in the world that will compensate!

I'm sorry, but Yahoo is not exactly reliable. A 1,000 CID V twin will still sound like an 80 CID V twin as long as the crank has the same angle. The larger engine will just have a lower-pitched sound. The rhythm is the same. You can argue that it's displacement until you're blue in the face but the fact of the matter is that crankshaft design and to a slightly smaller extent exaust acoustics play by far the largest roles in determining the sound of an engine.

ZV

 

[Ornery]

"You can argue that it's displacement until you're blue in the face but the fact of the matter is that crankshaft design and to a slightly smaller extent exaust acoustics play by far the largest roles in determining the sound of an engine."

Topic title is "what gives V8s their throaty exhaust note?"

Tiny V8s aren't 'throaty'. The answer to his question is the size of the cylinders, first and foremost.

 

[Demon-Xanth]

Roger:
I believe it has to do with the pulses hitting the barrier between the hot exhaust air and the reletively cold ambint air.


And about Ferraris, a 348 Testarossa only did 14.8 in the 1/4. Tons of cars will waste it. Back in the '80s when everything became suck, sports cars were not spared. (one year, the Corvette's engine options ranged from a 165HP base to 210HP top option)

 

[Zenmervolt]

Originally posted by: Ornery
"You can argue that it's displacement until you're blue in the face but the fact of the matter is that crankshaft design and to a slightly smaller extent exaust acoustics play by far the largest roles in determining the sound of an engine."

Topic title is "what gives V8s their throaty exhaust note?"

Tiny V8s aren't 'throaty'. The answer to his question is the size of the cylinders, first and foremost.

Again, exaust design can do a lot. Porsche's 2.5 litre inline four is a good example of this. Listen to the idle of a 924S or a 944 with the stock exaust system and it will sound deeper and more mellow than just about any other 4-cylinder car.

ZV

 

[geno]

It's the displacement that makes the American V8s more 'throaty', not the cross-plane VS flat-plane configuration

It's a combination of the two. Flat plane cranks make more of a poppy/buzzy noise, as do small displacement per cyl motors. However, the cross plane crank gives more of a "lumpiness" to the sound of the motor. Think about BMW's 4L V8 and compare it to a cross plane V8 like Ferrari's (granted, different displacents) they have completely distinct sounds. I know, different heads, different boreXstroke, but IMO, you can't deny that crank layout plays a big part in the sound of the motor. The Ferrari sounds like a motorcycle while the BMW has a smoother traditional V8 hum to it

 

[Ornery]

The point is, our rice boyz are trying to get that sound via exhaust tips, which is NEVER going to happen. Some of them go as far as putting headers and exotic exhaust systems on. It still ain't gonna happen! You can't make a weedwacker sound like a Harley!

 

[geno]

our rice boyz are trying to get that sound via exhaust tips

True, you can only do so much to change the tone of a motor - and as they've proven, it's very easy to ruin it BUT - don't forget about the legions of V6 Blazers/Explorers out there that try to duplicate the sound of a V8 with 5" tips. If anything, I noticed that junk a long time before ricing was a fad. Any truck that comes with a V6, but is available with a V8, you can count on finding people welding massive tips that look like bazookas on the back of their beat up 89 Blazer

 

[NuKe9]

Originally posted by: WinkOsmosis

Originally posted by: TechnoKid I believe one of either the IRL, or CART, or F1 engines is small displacement V8, but can rev to like 13,000 rpm. This is because the stroke of the engine is much shorter.

Those little nitro engines for RC cars rev to like 25,000 rpm :Q.

There are some that turn over 40,000 RPM!! Put out close to 2HP as well, not bad for a 2.1CC engine.

Example

 

Roger:
I believe it has to do with the pulses hitting the barrier between the hot exhaust air and the reletively cold ambint air.

Incorrect sir, the exhaust gasses are leaving the combustion chamber faster than the speed of sound.
If you could dump the exhaust directly into a chamber with the contents (air) heated to 1,200 F, it would still make the same sound.

 

[ElFenix]

Originally posted by: Zenmervolt Again, exaust design can do a lot. Porsche's 2.5 litre inline four is a good example of this. Listen to the idle of a 924S or a 944 with the stock exaust system and it will sound deeper and more mellow than just about any other 4-cylinder car.

ZV

and with cylinder chambers the size of a 302 i would expect it to sound deeper.

 

[bob4432]

Originally posted by: Roger
No,no,no !

Why would it burn the exhaust valves?

If you run a engine with open exhaust ports, the exhaust valves will burn, not because of the scavenging effect, but because when you shut the engine down, cold air will enter through the open exhaust port, thus warping the extremly hot exhaust valve.
In fact, removing the exhaust manifolds and pipes, you drastically reduce the scavenging effect and lose horsepower and torque.

Gasoline does not explode inside internal combustion engines, it burns rapidly.
A flame front starts at the spark kernal between the spark plugs eletrodes, this flame front propigates across the combustion chamber, preignition (Ping, detonation) is gasoline exploding inside the cylinder(s), this causes a high pressure wave to travel very rapidly, this wave makes the engine block ring like a bell, thus you hear it as "ping".

Ok smart guys, here's a good question for you, let's see how everyone's memory is (I asked and answered this question before), what makes the exhaust gasses so loud ?

here is your answer!! this is it, the headers / manifolds keep the exhause valves "insulated" and them cool slowly. there are reason why atleast all the engines i have seen have some type of header / manifold. even the ones making 5000+HP

 

[bob4432]

Originally posted by: Nebor

Originally posted by: OS

Originally posted by: Iron Woode

Inserts sound of 1968 Hemi Dart pulling a 10 sec 1/4 mile ET.

**Boy Yeah**

Take that ferrari!

[FnF]

You owe me a 10 sec car

[/FnF]



[FnF]

what's the retail on one of those?
more than you can afford buddy, ferrari "vroom, vroom"

[vin diesel]

smoke him

[/vin diesel]

[/FnF]

The funny thing is, people think that's realistic... Sure, some ricer might beat a Ferrari off the line.... but get up over 100mph, and Ferrari precision reigns.

older american muscle cars went straight well, but you have to setup a car quite a bit different for "real" handling and traction the way a autocross car travels.

 

[bob4432]

Originally posted by: Zenmervolt

Originally posted by: Ornery
"You can argue that it's displacement until you're blue in the face but the fact of the matter is that crankshaft design and to a slightly smaller extent exaust acoustics play by far the largest roles in determining the sound of an engine."

Topic title is "what gives V8s their throaty exhaust note?"

Tiny V8s aren't 'throaty'. The answer to his question is the size of the cylinders, first and foremost.

Again, exaust design can do a lot. Porsche's 2.5 litre inline four is a good example of this. Listen to the idle of a 924S or a 944 with the stock exaust system and it will sound deeper and more mellow than just about any other 4-cylinder car.

ZV

engine design. the design that porsche uses is not the same as toyota

 

[bob4432]

many factors determine what a engine will sound like. cam, crank, valvetrain, compression, turbo/blower, heads, it all adds up in the end. i don't think there is any 1 item that does it, but the combination of all. i have heard some small (377 sbc) sbcs with very trick heads, a huge roller cam, 14:1 compression etc that sounded like a big block. this motor made well over 600HP though, but it wasn't a buzz saw

 

[Jejunum]

boxer engine's sound awsome v8 or not...

 

[sillymofo]

Originally posted by: TrueBlueLS
I've been thinking about this for a little bit now. Could it maybe be the length of the tips coming off the muffler that resonate?

GLASSPACKED

 

[bob4432]

Originally posted by: cr4zymofo

Originally posted by: TrueBlueLS
I've been thinking about this for a little bit now. Could it maybe be the length of the tips coming off the muffler that resonate?

GLASSPACKED

glasspacks suck