what determines similarity of the car engines sound the same and different between makes?

Question

for instance, a range rover HSE purrs unlike a defeder landrover 110 that grunts

Answer 1

It has to do with the displacement of the engine, and not only the displacement but the bore vs. the stroke. A 2.5L V6 has more torque than a 2.5L I4 (4 cyl.) because of the longer stroke but the 4 cylinder has a bigger bore which allows for higher revving power. The V6 would have much better bottom range power though. Because of that, the v6 will have a deeper sound than the 4 cyl. It also depends on how many intake and exhaust ports there are. Some are only 2 valves per cylinder and some are 4 and some are 5. 4 or 5 valves per cylinder will have a "throatier" sound that only 2 valves per cylinder. The next biggest thing is the headers, and exhaust. The diameter of the exhaust pipes and design/shape of the muffler probably have the biggest impact on the sound. You could take a common car like the integra 1.8L and put one kind of exhaust say a GReddy 2.5" exhaust with 4-2-1 headers and open cat with a GReddy muffler and then compare it to stock sound and then take that same car and put 4-1 headers with 2.25" exhaust of a different brand of muffler and exhaust and it would sound quite a bit different. The exhaust probably has the ability to make the biggest impact on the car's sound aside from what's under the hood(the size of the motor). A Mustang GT will always no matter what sound deeper than a 4 or 6 cylinder, you can bore or stroke a 4 or 6 cylinder, change the exhaust, port and polish the head all you want and it's never going to sound as deep as a GT and you can never make a GT have a real high pitched sound, it's just not possible with the difference in exhaust gas flow between the 3 motors(4,6,&8 cylinder) to sound similar. A 4 cylinder crotch rocket sounds different than a 4 cylinder car. The reason for this is the design of the motor and the fact that the exhaust is much shorter than the car (about 4 long as compared to about 15-20ft long). The shorter the exhaust, the louder and more high pitched it is. Here's an example, take a straw or bottle and blow over top if it until it whistles, then take a that straw and cut it or use a smaller bottle - notice a difference? There's a change in pitch because of the volume of air that is being pushed out. So there's also some physics involved with the air flow that changes the pitch of the exhaust tone. Hope this helps.

Answer 2

Another factor the other posters have missed is how fast the engine goes.

A formula I car will sound a lot higher than a lazy gas guzzling yank muscle car.

I can't really tell the difference between the engine note of any US pushrod "square" V8's, and that's because they are the same basic design.

Likewise a four cylinder hatchback motor will sound like a four cylinder hatchback motor irrespective of maker.

And if it sounds as if it's farting then the owner is a boy racer with more money than sense.

Answer 3

Hello,

the sound of the eigine is determined by the following factors:

- how restrictive the intake is (restrictive - less air sucked by the engine -> silent and faint, conductive - more air, powerful combustion, grumbles)
- how the exhaust is (short or small diameter - you can hear all the clicking sound from the engine, long and big diameter - no mechanic noises, just the grumbles :D)
- naturally aspirated or supercharged/turbo (/superchargedturbo makes that lovely screaming :D)
- traction control working or not (when applied, the sound is deeper)
- the number of valves per cylinder (more get more air see above :D)
- cylinder layout (diesels, inline, V engines, boxers, Wankels have unique base sounds because of the differences in structure)
- mechanical sounds (eg. when the valvetrain is driven by chain, this gives a clicking sound, while belt driven valvetrain is more quiet).

To name a few...

Regards

Answer 4

its the engine manufacturer / designer, and yes the exhaust as a significant impact. Engines in the Defender are probably a very geriatric design (it may have been updated but i doubt its particualry modern. number of cylinders, exhause shape, manifold design, firing sequence, engine block material, engine bay damping) will have an effect.

bear in mind that quite a lot of engines are supplied to different marques, even different manufacturers

for example BMW supply the diesel engines on high end Land Rovers (Range Rover & Disco)

some manufacturers sourcre engines form a common source (eg VW group: VW, Audi, Seat, Skoda)

Answer 5

A manufacturer can make a car engine sound exactly as they wish with the use of the exhaust system.
Withinreson that is. A 4 cylinder 900cc is never going to sound like a V12.

But they can make a car sound quiet or sporty depending on its image and market.

Answer 6

in the ford crown victoria fairly for PATROL autos its no longer lots. The commonplace output of the two.4l V8 is 224 hp. The cop vehicle has a twin exaust which bumps the hp to 236. The torque besides the fact that is larger lots greater. Thanx for asking!

Answer 7

The type of engine, number of cylinders, type of exhast, how it is tuned. There are loads of factors! You can make most engines sound good with the right exhaust.

Answer 8

CC