[Boss330]

Originally Posted by CanAutM3

Good post.

Two small precisions though:

• The configuration of a cross plane vs flat plane crank does alter firing order by definition. Firing order is in part dictated by the geometry of the piston movements.
• The S63 does not use the crossing of exhaust between banks to optimize scavenging, but rather to provide even exhaust pulses to the turbos.

Agreed on the firing order is changed by definition between a flat plane and cross plane V8.

IMHO, the S63 benefits from both the better scavenging of the cross bank exhaust manifold layout as well as from the even pulses to the turbo.
AFAIK, the scavenging problems related to the cross plane layout means less effective evacuation of the exhaust because of the two consecutive exhaust pulses "fighting against each other" as the exhaust pulses into the manifold. This both reduces power and causes disruptions to the exhaust flow in the manifold.

IMO, the scavenging issues of the cross plane design also affects the effectiveness of the turbo. Both from a lag perspective as well as from a performance perspective. The uneven exhaust pulses not only create an imbalance in flow, but also creates variations in the flow speed of the exhaust gases (which is part of the scavenging problems).

I believe that the S63 benefits both from the even pulses as well as it does from the better scavenging. Meaning that each of the two turbos has a constant flow of exhaust gas from 4 cylinders at the same frequency and gas flow speed. Better scavenging means more exhaust gases at a higher speed compared to a manifold with poor scavenging.

Or have I gotten this all backwards?

[Law]

Originally Posted by Boss330

Not sure who's ridiculous, but since you used a lot of my references in your post it seems you consider me ridiculous...

Let me just repeat, for the third time, that the S55 exhaust sound seems to be a love it or loathe it sound. I never posted that it sounds great/good or whatever in my previous replies here. But that it has a distinctive sound, not like any other car on the market (which again can be both a good or bad thing, depending on if you like the S55 sound or not).

Just like the E46 M3 exhaust sound was heavily debated and split opinions, so it seems the S55 does. Perhaps because they both share the same basic exhaust layout and some shared sound qualities.

The S65 sounds good, but has a distinctive V8 sound track that any cross plane crank V8 has to share, unless there is a 180 degree header installed. Like on the original Ford GT40 or on the S63 in the M5/M6. You can immediately distinguish the S63 from the N63 (or from any other cross plane V8), due the exhaust manifolds. The 180 degree exhaust manifold actually diverts exhaust from two cylinders on one bank over to the collector for the opposite cylinder bank, and vice versa. By doing this you eliminate one of the drawbacks of the cross plane crank V8, namely the problem that you have two cylinders on one bank firing consecutively. This causes backpressure in the exhaust manifolds and less effective exhaust scavenging.

Changing the firing order doesn't alter the basic sound characterstics of a cross plane V8, it only changes the sequence of firing between the cylinders. But on ANY cross plane crank V8 you will allways have two cylinders on each bank firing consecutively, creating that typical V8 burble (that burble is actually the audible evidence of the backpressure and scavenging issues on a cross plane V8).

The cross plane V8 has a uneven firing order between the two cylinder banks:

R-L-L-R-L-R-R-L

As opposed to a flat plane crank V8 (Ferrari or Mustang GT350):

R-L-R-L-R-L-R-L

So regardless of firing order, the distinctive V8 burble will allways be present, unless you have a 180 degree header which duplicates a flat plane crank V8's exhaust pulses by "criss crossing" the cylinder banks into the L and R collector:

Firing order:..............R-L-L-R-L-R-R-L
Collector sequence: R-L-R-L-R-L-R-L

Which is why the F10 M5 doesn't sound like a regular V8, but the E9x M3 does...


Listen to the Mustang GT and M3 rev next to each other, or the Corvette and M3 accelerating. And even though it's possible to distinguish them, it's not like a night and day difference. Like a V8 and a V12 or a straight 6 and a V8.



In conclusion, I neither own a F8x or have said here that the S55 exhaust sound is good or bad. Just that it's a distinctive sound, and more so than the S65 exhaust sound. The S65 (IMO) is more comparable to a few other V8 powered cars, than the S55 is to any other car out there AFAIK

I appreciate your taking the time to attempt to school us on the differences between a flat vs. cross plane crank V8s, but most of us know these differences enough to know that your argument is flawed.

Not all flat plane V8s are created equal. Likewise, not all cross plane V8s are created equal.

Yes, its quite common knowledge that cross-planes and flat-planes sound fundamentally different as the former creates an uneven pulsing that yields an exhaust "burble", this is nothing new and the similarities end here. Sure there is a more audible "burble" in most cross-planes compared to flat-planes but grouping all cross-planes together is quite deplorable.

About the only things something like a C6 Corvette and an E9X M3 share are the cylinder count and cross plane crank. Even though both are cross-planes, the firing order of the cylinders are completely different, which yields a different sound, whether you admit it or not.
LS engines and many other "traditional" American V8s don't even have DOHC for crying out loud.
Maybe you should also try listening to an OHV, SOHC, and DOHC engine side by side, also quite different.

I also noticed you failed to make any mention of engine displacement.
And why would you, even the little logic you have left in your argument would know that any implication that an OHV 6.2L and a DOHC 4.0L are the same is completely ludicrous.
Even if we compare a DOHC 6.2L cross-plane (a la C63's M156) to the 4.0L S65, they still make different noises.


Contrary to your belief, ignition firing orders are not static across all cross-plane engines and changing the firing order DOES alter the sound of any engine. Regardless of cross-plane or flat-plane, the firing orders can be designed and configured differently to the engine builder's needs.
With each unique firing sequence, there is a different sound. Plain and simple.

In this comparison, we'll continue to use the LS3 vs. the S65.

Note that GM and BMW number their cylinders & banks differently.
For the purposes of this comparison, I provide the cylinder numbers fired in sequence as well as identification of the banks, where Right (R) and Left (R) banks are perceived from looking at the engine bay from the front of the car.

LS3 6.2L
1-8-7-2-6-5-4-3
R-L-R-L-L-R-L-R

S65 4.0L
1-5-4-8-7-2-6-3
L-R-L-R-R-L-R-L

As you can see, the LS3 and S65 do not share firing sequences and even the alternating firing between the two banks are different.
I'm not sure where you got "R-L-L-R-L-R-R-L" but i'll just go ahead and say Wikipedia is not a reliable source if you're trying to make an educated argument "R-L-L-R-L-R-R-L" coincides with some [GM] crossplane V8s (i.e., 350 Chevy Small Block, 406 Big Block), but not all, and the LS3 and S65 don't share a sequence with the quoted, nor do they share a sequence with each other.

Your main fallacy is categorizing all cross-planes into one category because Wikipedia gave you a firing order that you thought applied to all cross-plane V8s.


Even the flat-planes make different noises.
You make the comparison of the new Shelby GT350 and Ferrari, but again, different engines & different sounds.
For the purposes of this comparison, we'll assume the Ferrari is a 458 Italia.

I'll repeat myself again, different displacements and firing orders yield different sounds.
5.2L vs. 4.5L
Different firing orders.
Different sounds.

In the following video, Jay Leno introduces his new GT350R and has Ford Performance Chief Engineer, Jamal Hameedi, walk him through the R&D as well as technical specs of the car and especially, the new engine.
Jay Leno consistently mentions how the new Shelby V8 is more akin to European counterparts being a DOHC ("quad cam") high-revving engine and continues to praise its sound.
Jamal admitted that part of the R&D process involved taking apart a Ferrari 458 engine.
Jay comments later that the GT350R still sounds distinct and different despite being a flat-plane crank like a Ferrari V8.
Jamal then tells him that a different firing order, along with increased displacement contributed to this distinctive sound.

Grouping all cross plane or flat plane V8s together and calling them the same demonstrates a very rudimentary understanding of V8 engines and engine-design altogether.

[Boss330]

Originally Posted by Law

I appreciate your taking the time to attempt to school us on the differences between a flat vs. cross plane crank V8s, but most of us know these differences enough to know that your argument is flawed.

Not all flat plane V8s are created equal. Likewise, not all cross plane V8s are created equal.

Yes, its quite common knowledge that cross-planes and flat-planes sound fundamentally different as the former creates an uneven pulsing that yields an exhaust "burble", this is nothing new and the similarities end here. Sure there is a more audible "burble" in most cross-planes compared to flat-planes but grouping all cross-planes together is quite deplorable.

About the only things something like a C6 Corvette and an E9X M3 share are the cylinder count and cross plane crank. Even though both are cross-planes, the firing order of the cylinders are completely different, which yields a different sound, whether you admit it or not.
LS engines and many other "traditional" American V8s don't even have DOHC for crying out loud.
Maybe you should also try listening to an OHV, SOHC, and DOHC engine side by side, also quite different.

I also noticed you failed to make any mention of engine displacement.
And why would you, even the little logic you have left in your argument would know that any implication that an OHV 6.2L and a DOHC 4.0L are the same is completely ludicrous.
Even if we compare a DOHC 6.2L cross-plane (a la C63's M156) to the 4.0L S65, they still make different noises.


Contrary to your belief, changing the ignition firing order DOES alter the sound of any engine and regardless of cross-plane or flat-plane, the firing orders can be designed and configured differently to the engine builder's needs.
With each unique firing sequence, there is a different sound. Plain and simple.

In this comparison, we'll continue to use the LS3 vs. the S65.

Note that GM and BMW number their cylinders & banks differently.
For the purposes of this comparison, I provide the cylinder numbers fired in sequence as well as identification of the banks, where Right (R) and Left (R) banks are perceived from looking at the engine bay from the front of the car.

LS3 6.2L
1-8-7-2-6-5-4-3
R-L-R-L-L-R-L-R

S65 4.0L
1-5-4-8-7-2-6-3
L-R-L-R-R-L-R-L

As you can see, the LS3 and S65 do not share firing sequences and even the alternating firing between the two banks are different.
I'm not sure where you got "R-L-L-R-L-R-R-L" but i'll just go ahead and say Wikipedia is not a reliable source if you're trying to make an educated argument "R-L-L-R-L-R-R-L" coincides with some [GM] crossplane V8s (i.e., 350 Chevy Small Block, 406 Big Block), but not all, and the LS3 and S65 don't share a sequence with the quoted, nor do they share a sequence with each other.

Your main fallacy is categorizing all cross-planes into one category because Wikipedia gave you a firing order that you thought applied to all cross-plane V8s.


Even the flat-planes make different noises.
You make the comparison of the new Shelby GT350 and Ferrari, but again, different engines & different sounds.
For the purposes of this comparison, we'll assume the Ferrari is a 458 Italia.

I'll repeat myself again, different displacements and firing orders yield different sounds.
5.2L vs. 4.5L
Different firing orders.
Different sounds.

In the following video, Jay Leno introduces his new GT350R and has Ford Performance Chief Engineer, Jamal Hameedi, walk him through the R&D as well as technical specs of the car and especially, the new engine.
Jay Leno consistently mentions how the new Shelby V8 is more akin to European counterparts being a DOHC ("quad cam") high-revving engine and continues to praise its sound.
Jamal admitted that part of the R&D process involved taking apart a Ferrari 458 engine.
Jay comments later that the GT350R still sounds distinct and different despite being a flat-plane crank like a Ferrari V8.
Jamal then tells him that a different firing order, along with increased displacement contributed to this distinctive sound.

Grouping all cross plane or flat plane V8s together and calling them the same demonstrates a very rudimentary understanding of V8 engines and engine-design altogether.

My response was a very rudimentary explanation to try to explain the basic differences there is between V8 engines. My experience on these forums have shown that quite many have no idea about what a flat plane crank and cross plane crank V8 is.

Start talking about things such as exhaust scavenging issues on the cross plane V8 and people seem to understand even less...

Which is why I did a short explanation as to why a cross plane V8 fundamentally will have similarities in exhaust sound with the distinctive burble that ALLWAYS will be present, regardless of ignition timing sequence. And as an engineer that work in the automotive industry with engines as my speciality I think I know more than the average car guy about engine design... And my knowlegde isn't from Wikipedia, which I think you would have found out by going through my history on these forums...

Of course engine displacement, compression ratio, combustion pressure, camshaft duration, exhaust system layout etc is relevant to an engine's sound.

The firing order I used as an example, was simply just to illustrate the sequential firing on the same cylinder bank. I never claimed it was for a specific engine. There's a bunch of firing orders for a cross plane V8 and to some extent that changes the specific sound, but the distinctive V8 burble can't be eradicated on a cross plane V8, regardless of firing order...

The Mustang GT in the first video is a DOHC engine, and the familiarity between the sound of the M3 and GT as they rev is clearly audible... BTW, the Ford Coyote DOHC has a fairly similar firing order to the S65:

Coyote: 1-5-4-8-6-3-7-2
M3 S65: 1-5-4-8-7-2-6-3

Compared to the previous Ford V8's: 1-3-7-2-6-5-4-8

This video illustrates the BASIC difference in the sound of a cross plane vs flat plane. You can have variations of a theme on both engines, but it doesn't matter if you have ohv, sohc, dohc etc. The basic frequence and distribution of exhaust pulses into each exhaust manifold simply doesn't change as long as you either have a cross plane or flat plane crank.

On it's own, a SOHC or DOHC system has no effect on exhaust sound, after all those are just denominators for how many camshafts the engine has. A 2V or 4V cylinder head can influence sound but doesn't necessarily do so to any noticeable level. However a difference in compression ratio, and/or combustion pressure, certainly affects the loudness of the combustions and thereby the noise level of the exhaust.

The first generation Mustangs that had the 4,6l modular engine is a good example of how little difference there is in sound between the std 4.6 GT SOHC V8 and the Cobra DOHC V8:

Jay Leno certainly is a interesting guy and knows a lot. But the Mustang has had a DOHC V8 available in the Cobra, or std in the GT, in the last 15 years. Yes, being a DOHC makes it more "European", but it's nothing new. And as we all know, the Coyote DOHC in the GT sounds very different from the Voodoo DOHC (flat plane) in the GT350. So contrary to Jay Leno's continual reference to the DOHC layout, that's not what makes the GT350 sound different from the Mustang GT... It's the crank layout.

Yes, cross plane V8's do have different sound. You can definitely tell the difference between a old Chevy Suburban and a M3, but just like a BMW I4 and a Fiat Punto I4 sounds different, it's very easy to tell they both are I4 engines. The Mustang GT (5l DOHC V8) and M3 (4l DOHC V8) that was in my previous post does not sound all that different, and there is no problem telling they are both traditional cross plane V8 engines... In fact, in a double blind test, listening to them rev next to each other, or accelerating away, I believe that you would have people mixing the cars. Put a S55 engined car next to any other car, not many would have a problem telling which one was the S55 IMHO. Which basically was my original point.

[CanAutM3]

Originally Posted by Law

LS3 6.2L
1-8-7-2-6-5-4-3
R-L-R-L-L-R-L-R

S65 4.0L
1-5-4-8-7-2-6-3
L-R-L-R-R-L-R-L

Hmmmm,

From an exhaust pulse standpoint, wouldn't those two yield the exact same result (simply interchanging left from right banks) ?

[CanAutM3]

Originally Posted by Boss330

Agreed on the firing order is changed by definition between a flat plane and cross plane V8.

IMHO, the S63 benefits from both the better scavenging of the cross bank exhaust manifold layout as well as from the even pulses to the turbo.
AFAIK, the scavenging problems related to the cross plane layout means less effective evacuation of the exhaust because of the two consecutive exhaust pulses "fighting against each other" as the exhaust pulses into the manifold. This both reduces power and causes disruptions to the exhaust flow in the manifold.

IMO, the scavenging issues of the cross plane design also affects the effectiveness of the turbo. Both from a lag perspective as well as from a performance perspective. The uneven exhaust pulses not only create an imbalance in flow, but also creates variations in the flow speed of the exhaust gases (which is part of the scavenging problems).

I believe that the S63 benefits both from the even pulses as well as it does from the better scavenging. Meaning that each of the two turbos has a constant flow of exhaust gas from 4 cylinders at the same frequency and gas flow speed. Better scavenging means more exhaust gases at a higher speed compared to a manifold with poor scavenging.

Or have I gotten this all backwards?

My understanding is that exhaust "scavenging" is not really important in the design of most FI engines, especially turbocharged ones. On a turbo engine, you want the turbo to be as close as possible to the exhaust port to minimize lag, hence it makes it incompatible to having the proper exhaust runner length for a tuned resonance (compare the exhaust manifolds of the S54 vs S55 or S65 vs S63). Further, the backpressure created by the turbine also interferes with the resonance effect. Finally, with an intake charge that is pressurized, it is possible to use that positive pressure to "push" the residual exhaust gases out of the combustion chamber with proper valve overlap, thus negating the need for "scavenging".

[Boss330]

Originally Posted by CanAutM3

My understanding is that exhaust "scavenging" is not really important in the design of most FI engines, especially turbocharged ones. On a turbo engine, you want the turbo to be as close as possible to the exhaust port to minimize lag, hence it makes it incompatible to having the proper exhaust runner length for a tuned resonance (compare the exhaust manifolds of the S54 vs S55 or S65 vs S63). Further, the backpressure created by the turbine also interferes with the resonance effect. Finally, with an intake charge that is pressurized, it is possible to use that positive pressure to "push" the residual exhaust gases out of the combustion chamber with proper valve overlap, thus negating the need for "scavenging".

Of course. How could I forget that scavenging isn't as critical, or actually not such an issue, on a FI engine. Point taken and I agree 100%

[Boss330]

Originally Posted by CanAutM3

Hmmmm,

From an exhaust pulse standpoint, wouldn't those two yield the exact same result (simply interchanging left from right banks) ?

Further, if the cylinders are named (numbered) differently, it does not necessarily mean that the geometric firing order is different.

As allways, you spot the details

Those two firing orders are nothing more than a mirror image of each other. In effect the firing order of the LS3 and S65 is the same, but cylinder banks are interchanged (like looking at the engine from the front of the engine bay or from the rear of the engine bay and switching which cyl bank was left and right as you changed position).

[CanAutM3]

Originally Posted by Boss330

And as we all know, the Coyote DOHC in the GT sounds very different from the Voodoo DOHC (flat plane) in the GT350. So contrary to Jay Leno's continual reference to the DOHC layout, that's not what makes the GT350 sound different from the Mustang GT... It's the crank layout.

As a tidbit, IIRC, even the Voodoo is not a "pure" flat plane V8 as it does not have separate intake manifolds/plenums.

[CanAutM3]

Originally Posted by Boss330

As allways, you spot the details

Those two firing orders are nothing more than a mirror image of each other. In effect the firing order of the LS3 and S65 is the same, but cylinder banks are interchanged (like looking at the engine from the front of the engine bay or from the rear of the engine bay and switching which cyl bank was left and right as you changed position).

It's a bit more complex than this. The numbering nomenclature is different. The LS3 has odd on the right and even on the left while the S65 has 1-4 on the left and 5-8 on the right.

[Boss330]

Originally Posted by CanAutM3

As a tidbit, IIRC, even the Voodoo is not a "pure" flat plane V8 as it does not have separate intake manifolds/plenums.

The Voodoo has also chosen a less used UDUD instead of UDDU crank.

U meaning Up and D meaning Down

GT350 crank


Ferrari UDDU flat plane crank


One drawback of the UDUD crank is that more material is needed to balamce the crank, as can be seen on the counterweights on the GT350 crank

[Boss330]

Originally Posted by CanAutM3

It's a bit more complex than this. The numbering nomenclature is different. The LS3 has odd on the right and even on the left while the S65 has 1-4 on the left and 5-8 on the right. But their firing order are indeed different.

Ok, I just glanced real quick on your comment and thought they where just mirrored. A bit late over here now...

I get that the numbering of cylinders are different between BMW and GM, but wasn't the firing orders in the example given using the same numbering system?

EDIT:
Ahhh, you where talking about exhaust pulses, not necessarily firing order. And on the LS3 and S65 the exhaust pulses are mirrored, but firing order is different.

[Law]

Originally Posted by CanAutM3

Hmmmm,

From an exhaust pulse standpoint, wouldn't those two yield the exact same result (simply interchanging left from right banks) ?

Originally Posted by Boss330

As allways, you spot the details

Those two firing orders are nothing more than a mirror image of each other. In effect the firing order of the LS3 and S65 is the same, but cylinder banks are interchanged (like looking at the engine from the front of the engine bay or from the rear of the engine bay and switching which cyl bank was left and right as you changed position).

Originally Posted by CanAutM3

It's a bit more complex than this. The numbering nomenclature is different. The LS3 has odd on the right and even on the left while the S65 has 1-4 on the left and 5-8 on the right.

CanAutM3 You edited out the questions on numbering sequence before I could answer your question. But based on your later post, it looks like you answered it yourself.

Boss330 Again, you continue to oversimplify the situation.

Originally Posted by Boss330

My response was a very rudimentary explanation to try to explain the basic differences there is between V8 engines. My experience on these forums have shown that quite many have no idea about what a flat plane crank and cross plane crank V8 is.

Start talking about things such as exhaust scavenging issues on the cross plane V8 and people seem to understand even less...

Which is why I did a short explanation as to why a cross plane V8 fundamentally will have similarities in exhaust sound with the distinctive burble that ALLWAYS will be present, regardless of ignition timing sequence. And as an engineer that work in the automotive industry with engines as my speciality I think I know more than the average car guy about engine design... And my knowlegde isn't from Wikipedia, which I think you would have found out by going through my history on these forums...

Of course engine displacement, compression ratio, combustion pressure, camshaft duration, exhaust system layout etc is relevant to an engine's sound.

The firing order I used as an example, was simply just to illustrate the sequential firing on the same cylinder bank. I never claimed it was for a specific engine. There's a bunch of firing orders for a cross plane V8 and to some extent that changes the specific sound, but the distinctive V8 burble can't be eradicated on a cross plane V8, regardless of firing order...

The Mustang GT in the first video is a DOHC engine, and the familiarity between the sound of the M3 and GT as they rev is clearly audible... BTW, the Ford Coyote DOHC has a fairly similar firing order to the S65:

Coyote: 1-5-4-8-6-3-7-2
M3 S65: 1-5-4-8-7-2-6-3

Compared to the previous Ford V8's: 1-3-7-2-6-5-4-8

This video illustrates the BASIC difference in the sound of a cross plane vs flat plane. You can have variations of a theme on both engines, but it doesn't matter if you have ohv, sohc, dohc etc. The basic frequence and distribution of exhaust pulses into each exhaust manifold simply doesn't change as long as you either have a cross plane or flat plane crank.


On it's own, a SOHC or DOHC system has no effect on exhaust sound, after all those are just denominators for how many camshafts the engine has. A 2V or 4V cylinder head can influence sound but doesn't necessarily do so to any noticeable level. However a difference in compression ratio, and/or combustion pressure, certainly affects the loudness of the combustions and thereby the noise level of the exhaust.

The first generation Mustangs that had the 4,6l modular engine is a good example of how little difference there is in sound between the std 4.6 GT SOHC V8 and the Cobra DOHC V8:


Jay Leno certainly is a interesting guy and knows a lot. But the Mustang has had a DOHC V8 available in the Cobra, or std in the GT, in the last 15 years. Yes, being a DOHC makes it more "European", but it's nothing new. And as we all know, the Coyote DOHC in the GT sounds very different from the Voodoo DOHC (flat plane) in the GT350. So contrary to Jay Leno's continual reference to the DOHC layout, that's not what makes the GT350 sound different from the Mustang GT... It's the crank layout.

Yes, cross plane V8's do have different sound. You can definitely tell the difference between a old Chevy Suburban and a M3, but just like a BMW I4 and a Fiat Punto I4 sounds different, it's very easy to tell they both are I4 engines. The Mustang GT (5l DOHC V8) and M3 (4l DOHC V8) that was in my previous post does not sound all that different, and there is no problem telling they are both traditional cross plane V8 engines... In fact, in a double blind test, listening to them rev next to each other, or accelerating away, I believe that you would have people mixing the cars. Put a S55 engined car next to any other car, not many would have a problem telling which one was the S55 IMHO. Which basically was my original point.

Nobody on this thread denies that flat-planes sound fundamentally different from cross-plane cranks.
So let's not get carried away because nobody here said a cross-plane sounds like a flat-plane.

Let me also point out that you're quoting the wrong person. I wanted you to listen to the chief engineer of Ford Performance and his answers to Jay Leno, not to take Jay Leno's commentary as truth. Jay Leno's commentary on the "European"-like characteristics is to be taken with a grain of salt. Mainly, this comment is only important because it leads on to the topic of sound where Jamal explains how even flat-plane cranks from two different engine builders can sound very different. So again, you're getting carried away.

The point of my previous post was to demonstrate how within the category of cross-plane V8s, there are many different ways to configure firing sequences, head design, displacement, etc., which lead to a different sound.
Will they sound like cross-plane V8s? Of course, because they are cross-plane V8s. But that doesn't mean they sound the same.
I'm glad you acknowledge the design differences upon an in depth discussion, but I still disagree that an S65 would be mistaken for a Coyote or LS V8 (and vice-versa) as you've claimed in this thread.

Sure if you're talking about Joe Schmo, he might think they [Coyote & S65] sound the same.
But you might have the same guy unable to tell a fart can Civic and S55-powered F8X apart.
So this is seriously a moot point.

[Boss330]

Originally Posted by Law

CanAutM3 You edited out the questions on numbering sequence before I could answer your question. But based on your later post, it looks like you answered it yourself.

Boss330 Again, you continue to oversimplify the situation.




Nobody on this thread denies that flat-planes sound fundamentally different from cross-plane cranks.
So let's not get carried away because nobody here said a cross-plane sounds like a flat-plane.

Let me also point out that you're quoting the wrong person. I wanted you to listen to the chief engineer of Ford Performance and his answers to Jay Leno, not to take Jay Leno's commentary as truth. Jay Leno's commentary on the "European"-like characteristics is to be taken with a grain of salt. Mainly, this comment is only important because it leads on to the topic of sound where Jamal explains how even flat-plane cranks from two different engine builders can sound very different. So again, you're getting carried away.

The point of my previous post was to demonstrate how within the category of cross-plane V8s, there are many different ways to configure firing sequences, head design, displacement, etc., which lead to a different sound.
Will they sound like cross-plane V8s? Of course, because they are cross-plane V8s. But that doesn't mean they sound the same.
I'm glad you acknowledge the design differences upon an in depth discussion, but I still disagree that an S65 would be mistaken for a Coyote or LS V8 (and vice-versa) as you've claimed in this thread.

Sure if you're talking about Joe Schmo, he might think they [Coyote & S65] sound the same.
But you might have the same guy unable to tell a fart can Civic and S55-powered F8X apart.
So this is seriously a moot point.

Your arguments seem to be more about telling me how little I know and how little my comments on the topic means to you, than to actually discuss it on a non personal level...

Doesn't matter. I think the S65 sounds great, but still clearly recognizeable as a cross plane V8 and not that dissimilar from some other modern V8's. But that's my subjective opinion and my hearing. Just like we prefer different music and that what sounds good to one person can sound horrible to the next, so is our perception of exhaust noise as well...

BTW, I don't see that CanAutM3 has edited out his reply on exhaust pulse sequences...

AFAIK, what he said is that the exhaust pulse sequence (between the L and R cyl banks) is exactly the same on the LS3 and S65, just mirrored.

[Law]

Originally Posted by Boss330

Your arguments seem to be more about telling me how little I know and how little my comments on the topic means to you, than to actually discuss it on a non personal level...

Doesn't matter. I think the S65 sounds great, but still clearly recognizeable as a cross plane V8 and not that dissimilar from some other modern V8's. But that's my subjective opinion and my hearing. Just like we prefer different music and that what sounds good to one person can sound horrible to the next, so is our perception of exhaust noise as well...

Don't take it personal, was trying to stay on topic.
Agreed. Sound is subjective to begin with. My ears can easily pick up S65 even in a sea of other cross-planes. Its funny, I had a similar yet different conversation with another forum member years ago about being able to distinguish these sounds.
Maybe i really do have "spectacular ears" as he put it


Anyways, we can agree to disagree, but I enjoyed this conversation, good day

Originally Posted by Boss330

BTW, I don't see that CanAutM3 has edited out his reply on exhaust pulse sequences...

AFAIK, what he said is that the exhaust pulse sequence (between the L and R cyl banks) is exactly the same on the LS3 and S65, just mirrored.

I saw something underneath that I was going to reply to with a diagram showing how cylinders are numbered but I was away from my desk and on my phone. Not to worry, he seems to have figured it out

[Jay-K]

nice,

[CanAutM3]

Originally Posted by Law

CanAutM3 You edited out the questions on numbering sequence before I could answer your question. But based on your later post, it looks like you answered it yourself.

Originally Posted by Law

I saw something underneath that I was going to reply to with a diagram showing how cylinders are numbered but I was away from my desk and on my phone. Not to worry, he seems to have figured it out

It wasn't a question, it was a statement (it can still be read in this post from Boss330) . I wanted to highlight the fact that your example was exacerbated by a different numbering convention. I decided to delete the point to avoid further confusion.

The main point remains, the exhaust pulses from a cross plane V8 remain the same regardless of firing order.

I do agree however that additional subtleties can be brought to the engine sound through intake and exhaust design for example. My wife's B7 S4 sounds very different than my E92 did, both cross plane V8s of similar displacement. But the basic cross plane V8 signature still remains clearly identifiable .

[Law]

Originally Posted by CanAutM3

It wasn't a question, it was a statement (it can still be read in this post from Boss330) . I wanted to highlight the fact that your example was exacerbated by a different numbering convention. I decided to delete the point to avoid further confusion.

The main point remains, the exhaust pulses from a cross plane V8 remain the same regardless of firing order.

I do agree however that additional subtleties can be brought to the engine sound through intake and exhaust design for example. My wife's B7 S4 sounds very different than my E92 did, both cross plane V8s of similar displacement. But the basic cross plane V8 signature still remains clearly identifiable .

Further, if the cylinders are named (numbered) differently, it does not necessarily mean that the geometric firing order is different.

Ah, there it is.
The LS and S65 still fire at different intervals though, even geometrically.
They may seem like mirrors of each other on paper, but perhaps an illustration can clear the confusion.




Let's dissect.
Starting with the first 2 cylinders fired. Not mirror images at all.


Towards the middle of the sequence, where the 4th and 5th cylinders in the sequence fire. Again, not mirrored.


Then the last two cylinders in the sequence.



All in all, in this example, the LS3 is quite different than the S65, despite them both being cross-plane V8s.
Sure they both sound like cross-plane V8s, but the things mentioned in my previous posts (firing order, displacement, OHV/DOHC, etc.) contribute to a different exhaust note.
No, you can't literally tell which cylinder is firing at any moment, but when these different firing sequences repeat 3000 times a minute, they yield a different sound.

[Prince_of_Persia]

I like the look of the M2. They both sound terrible though.