Ferrari Sound

[jibbby]

RMS I'm a slow learner and don't get alot of things (women especially) I appologise....Remember I am not an engineer, a rocket scientest, a nuclear phys. etc.., I am a basic ham and egger contractor whom hammers nails into 2X4's for a living...An honorable trade that does not require very much brain power.....RMS, I am your basic back yard tinker with motors when ever possible mechanic...However, I am eager and willing to learn but unfortunately you guys have to put up with me...

I do get it now I think, thanks RMS. Let's see the impulses is the exhaust sound that is timed between each detonation from each cylinder (exhaust impulses) create the sound. Differs from inlines, V8's, etc like you said... Infact crossed impulse exhaust sounds is what you get from the xUZ-fe motors by stock design....However the Farrari motors I am thinking of are not inline 8 cyl motors, it is Ferrari 4.3 liter V8 and how different can the impulses be?..Farrari motor V8 detonates in the same firing order as let's say a 4.3L 3UZ.. How are the impulses that different? Does cam lift, higher revs, different independant TB's, etc.. on a V8 motor change impulse sounds that much?....

Now I am really lost RMS...It's ok though, I will just go grab a cold beer from the fridge and move onto the next thread....See ya...:beerchug:

 

[sloshua]

....................it is Ferrari 4.3 liter V8 and how different can the impulses be?..Farrari motor V8 detonates in the same firing order as let's say a 4.3L 3UZ.. How are the impulses that different? Does cam lift, higher revs, different independant TB's, etc.. on a V8 motor change impulse sounds that much?....

Now I am really lost RMS...It's ok though, I will just go grab a cold beer from the fridge and move onto the next thread....See ya...:beerchug:

First off-they are not the same firing order. The goal with the crossover headers is to make the UZ motors exhaust pulses hit the collector in a similar way to the ferraris despite the different firing order.

Think of a good header collector like this:
O O
O O

With the positions being:
1 2
4 3

You design a good header with the pulse entering in a circular pattern to encourage one pulse to pull the next out of the adjacent pipe. (Scavenging)

With that design in mind:

The firing order of the ferrari will fill one collector on one side of the engine with evenly spaced exhaust pulses in a nice circular evenly spaced 1,2,3,4 pattern. Smooth sound. Good scavenging. Good flow with smaller collector exit.

If by some way you were fortunate to have a nice collector on your lexus fed by one side of your engine you would get pulses more along the line of 1,23,4. This creates a rougher sound by having pulses 2 and 3 arrive in the collector at almost the same time acting more like 1 large long pulse. This also leads to worse scavenging, and the need for a larger collector exit to deal with the large pulse. The larger exit and subsequent pipe also lead to a deaper louder exhaust sound.

The solution to the problem is a crossover header like shown in the pictures in previous posts. Or a flat plane crank like a ferrari.

The other stuff you asked about changes exhaust tone some as well.

 

[KazeSupra]

Ok, what about changing the firing order...now I know this might sound like a long shot, couldn't you change the firing order to match something similar to a ferrari's? For instance, get your cams reground, and instead of getting them in the same order, have a couple of them moved around to suit a more ferrari-like numbers. I found this order in another thread:

From 1-8-4-3-6-5-7-2 to 1-8-7-2-6-5-4-3 or something of the like? Please let me know...

Chris.

 

[jibbby]

Wow, you guys are great.. If I can't match wits with you folks maybe I can make you all chuckle...I really am learning, but soon will be forgetting as I am now working on my third cold beer....:alcoholic:

Seriously, thanks for the clarification I now have a better understanding of it all...Scavenging is an important term that I had forgot about....I also thought the firing order was the same between the two motors.....Those Ferrari motors are really something else, it's just a darn shame their life expectancy is crap.....

 

[sloshua]

Ok, what about changing the firing order...now I know this might sound like a long shot, couldn't you change the firing order to match something similar to a ferrari's? For instance, get your cams reground, and instead of getting them in the same order, have a couple of them moved around to suit a more ferrari-like numbers. I found this order in another thread:

From 1-8-4-3-6-5-7-2 to 1-8-7-2-6-5-4-3 or something of the like? Please let me know...

Chris.

Would take a new crank to change the piston rotation order, cams to open the valves at the "New" right time, and ignition to fire the spark at the right time. I dont remember exactly what the benefit is other than exhaust timing. I think there are some balance issues as well. Not sure, read about it at one time, but dont remember.

 

[stevechumo]

I heard the Ferrari F430 roared going in the opposite way. It's very impressive with its high pitch. Very loud! However, when I heard the Lamborghini Murcialego driving right next to me, I think I love the Lambo's sound a lot more. It's Vrum! vrum! all the way with its deeper notes. I'm into more of a deeper notes guy than the high pitch notes.

The pipe routing is a key factor in making an exhaust sound different from the other exhausts. A 4-1, 4-2-1, or equal length will sound differently. However, the sizes and the materials of the pipes, the resonators, and the muffler all contribute to the notes.

 

[KazeSupra]

Would take a new crank to change the piston rotation order, cams to open the valves at the "New" right time, and ignition to fire the spark at the right time. I dont remember exactly what the benefit is other than exhaust timing. I think there are some balance issues as well. Not sure, read about it at one time, but dont remember.

Alright, another question. When making this 180 degree exhaust, is it more benificial to route them outer from one side to inner on other side into 4-1 collector, or can I route them into a 2-1 on one side, 2-1 on the other (let's say for the inners), then route them together into another 2-1, so it will look like a 4-2-1? I noticed that when I did a search, all of the ones that I saw were 4-1, but for space reasons, 4-2-1 might be a little easier to do.

And yes, I'm VERY much considering making these 180 degree headers...

 

[striker]

Euuhm yeah I think you could, but a part of the scavanging bennfit will be lost, RMS earlier pointed out that cross headers with 4-1 collectors are the way to go, although he didn't tell why, I delved into it a little deeper, and think that the reason for not doing 2-1 is indeed the scavenging, In the 4-1 vs twin 2-1 sound department I can only say, GO 4-1, I have RAW engineering hearders on my 20v striker and that sounds awsome. it'll give you a few HP on top aswell, though twin2-1 could gain some torque. Errol have you got something to ad about this?

in theory a smaler diameter pipe has a higher resonante frequency, and the bigger the damper the more silent you can get it by adding chambers and absorbing material, but on the other hand if left open all round it will be very loud.

grtz Thomas

 

[KazeSupra]

So you're saying that the 4-2-1 would probably be quieter than the 4-1? I suppose I can do 4-1. I wouldn't mind the quietness, because most of that will be negated once the go pedal is on the floor and both turbos are spooled...hehe. I also wouldn't mind the quietness because this is a street car and the wife probably wouldn't want to be drowned out while she's talking to me

Still interested in more information if anyone has any.

Thanks for everything so far.

Chris.

 

[striker]

sound is different not neccesarily louder. the pitch has changed if you've build it correctly. turbines are very nice dampers!

grtz Thomas

 

[KazeSupra]

turbines are very nice dampers!

That's what I keep hearing...

Well, I guess I should just do it and see how it turns out. I'm sure that by the time I get it done and if I don't like it, there might be some turbo manifolds made by then, LOL.

Good talking to you all.

Chris.

 

[sloshua]

http://www.ssheaders.com/header.htm Decent info. Remember they are usually referring to American V8s with the same firing order as the Lexus.

 

[KazeSupra]

I've seen that before, but I never really read it all the way...awesome article...now that I've read it, I'm definitely going to do it.

 

[stevechumo]

So you're saying that the 4-2-1 would probably be quieter than the 4-1?....

That's true. A 4-2-1 design will be quieter than a 4-1 design. As far as I know, the 4-2-1 design gives quicker power at lower RPM than the 4-1 design. In the sport compact street cars, 4-2-1 is more desirable. And the 4-1 is more for tracks, where the hi-end is more needed.

 

[KazeSupra]

I guess the question is, how much quicker? This is what I'm faced with so far:

4-2-1:
Easier to design
takes up less space
more low-end power
Slightly quieter
THE SOUND!

4-1
more top end
better scavaging
most optimum setup
THE SOUND!

All this on a 4.0L V8 making 200rwhp/L...mmm

Decisions, decisions...

 

[striker]

If You want mean sound? go for 4-1 with very good merge collectors and NO megaphones.

turbines are dampers because the effectivly break-up the presure wave you hear. and lets it exit in a twisting manner (ie turning around) without hardly any pulsing going on. just like a baffle would do, indirect pulse vs direct pulse

If you don't know what I mean, go to le-mans and listen to the corvettes comming by in the Arnage pitlane, that's presure pulse amplitude! WEAR EARPLUGS,

you can BTW use some of the Basstrap, and Bass reflectiontube calculations used in loudspeaker (google's your friend) design to get to a decent mufler design. do't go with straight through designs you allready know how they sound.

grtz Thomas

 

[KazeSupra]

Interesting ideas, Thomas. I want a screamer for my car. So what you're basically saying is to design my own muffler? Hmm, interesting concept...I don't know how well I'd do, but I'm sure I can come up with something.

On the collectors, which one do you think is better?

The mufflers I was considering are:

http://www.aeroexhaust.com/aero_turbine_3030.html
http://www.spintechmufflers.com/spintech/spintechindex.asp

let me know what you think.

Chris.

 

[ed_ma61]

well for a start the one on far right is a turbo collector....

the big pic in the middle is best. long taper, veturi collector. far left comes second, just has a shittier taper, and the crappy black pic isnt really a merge collector at all

 

[KazeSupra]

Right or left is a turbo collector? I pasted the one from Burns Stainless website, which is a turbo collector with a V-Band connector, on the far left. The reason I posted it is...well...I'm doing turbos

OK, just so I make sure I understand, if you number left - right 1 - 4, 1 is the turbo collector, 2 is the one you prefer, 3 is the crappy one, and 4th you didn't comment on, right?

 

[ed_ma61]

oops, far left (1) is a turbo collector?! my bad, could also double as a crappier merge collector. (i though it looked a bit heavy duty!)

far right (4) is also a turbo collector.

for a turbo, id be tempted to stick with 4 - simply for space reasons, and the gains with 1 would be minimal

for an NA header merge collector, the big pic (3) wins hands down