I do and in order to get it you must use a flat crank or 180* headers ..Anybody built headers like that for the Fiero as it would be a more of a major accomplishment to have a flat crank built and cams ground and an ignition fuel managment system built to run it so I am really reaching in that respect I hope someone has built a bundle of snakes and perhaps there is at least a sound byte of the exhaust system. I would love to hear your comments on getting that sound
I'm sure Ferrari has that sound copyrighted like Harley Davidson... So it would be hard to find.
EDIT: You may want to look at SuperTrapp exhaust. Not sure how close to a Ferrari it will sound but you can adjust the sound and performance of your Fiero. http://www.supertrapp.com/technology/index.asp
[This message has been edited by FierociousGT (edited 10-31-2007).]
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02:33 AM
Fierobsessed Member
Posts: 4782 From: Las Vegas, NV Registered: Dec 2001
I looked into possible ways of modifying a V8 for firing order to make it sound like a Ferrari. Because of the crankshaft shape, we all know its a bummer I gave up. I managed to find a way to get it to fire 4 cylenders on one side, then the 4 on the other side, it would probably sound like poop though! 1-2-4-8-6-3-7-5 Just with a cam change. However, If you have one collector with cylenders: 8-5-3-2, and on the other 7-6-4-1, You will eliminate the double pulse that each collector recieves by the uneven left to right firing of a V8. But the thought of criscrossing 4 pipes makes me want to puke. The flat crank and custom cam is the way to do it. I still think that the engine has got to be DOHC to achieve the sound as well, something about a 4 valve engine, and high RPMs. Sounds like fun! Obviously it isn't going to be the most fun task to locate a flat-plane/180 crank, they charge an arm and both legs for them. I believe Crower will custom build them, maybe even Scat. They also make an older Iron Duke look to be perfectly balanced. Second order harmonic vibrations of a 4 cylender, effectivly doubled. Sure makes the 180 degree headers seem like the way to go. Four pipes over the transmission.
The 3.4 DOHC has some potential to sound like one, you know this already. But it still sounds like any crusty old GM V6 60 degree at idle and low RPM's. For me, the jury is sill out, pending completion of my car. You have to give it up to Nissan though, their VQ35, with its exhaust system has got a really unique and pleasant sound, slightly resembling a Ferrari, but notably different too. I don't know if it is the engine, or that really overengineered length of pipe and muffler doing that to the sound. Im not personally going for the sound, but I think with the way I put the exhaust together, I will be thrilled with my exhaust note off idle. After all, a (V12) Ferrari is like a pair of V6's tied at the crank 30 degrees out.
[This message has been edited by Fierobsessed (edited 10-31-2007).]
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04:18 AM
Will Member
Posts: 14280 From: Where you least expect me Registered: Jun 2000
I tried a Supertrapp muffler on my 2.8 V6. It sounded like crap. It was loud and raspy, and hissed like an exhaust leak during hard acceleration. It sounded more like a Honda than a Ferrari.
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09:05 AM
dguy Member
Posts: 2416 From: Beckwith Township, ON, Canada Registered: Jan 2003
Originally posted by Fierobsessed: The 3.4 DOHC has some potential to sound like one, you know this already.
Yes I am currently working on a solution using the exhaust pulse method ..although I really like the sound as is, it needs to be higher in pitch http://videos.streetfire.ne...4d9-99d8015283c4.htm in this video it is too low sounding probably due to the turbo mufflers resonance frequency
[This message has been edited by Erik (edited 10-31-2007).]
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07:30 PM
PFF
System Bot
Erik Member
Posts: 5625 From: Des Moines, Iowa Registered: Jul 2002
Originally posted by Erik: any v engine although more leaning towards a 90 * v8 with 90* firing without having to use a flat crank
Well that's easy. Put a crossover in exactly the right spot and you don't have to deal with the even-odd-odd exhaust pulses. Resonators + small mufflers.....
Well that's easy. Put a crossover in exactly the right spot and you don't have to deal with the even-odd-odd exhaust pulses. Resonators + small mufflers.....
I do and in order to get it you must use a flat crank or 180* headers ..Anybody built headers like that for the Fiero as it would be a more of a major accomplishment to have a flat crank built and cams ground and an ignition fuel managment system built to run it so I am really reaching in that respect I hope someone has built a bundle of snakes and perhaps there is at least a sound byte of the exhaust system. I would love to hear your comments on getting that sound
Contact : Doug Chase (he's a member here) chaseracedotcom
He used to posses a set (180* headers) for the 2.8, so unique I'm sure he still has 'em.
Norm
P.S. :
Some may remember Doug was involved in auto-X w/his Formula and off road rallied an '85? for awhile, still pit teams, and was on the 2nd place team on that Speed Channel reality (yeah right!) show 'Setup'. I thought Doug managed to resist the personality conflict trolls remarkably well, I was disappointed that the show wasn't more technically oriented. I couldn't quite figure out just what audience the producers were trying to entertain, but they outfitted and pseudo campaigned 10 Solstices if that means anything.
So just what was that 'hot-swap" tire issue anyway, they didn't ever make that clear that I can remember?
[This message has been edited by gt88norm (edited 10-31-2007).]
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10:11 PM
Erik Member
Posts: 5625 From: Des Moines, Iowa Registered: Jul 2002
Ok, I'm at kind of a loss. How does the 180 degree exhaust alter the sound? The flat crank too? Enquiring minds wanna know.
Its the firing pulses ..Taking a V8 for example, a cross plane crank will fire every 90* and give you a burbling rumbling sound so common to the typical American V8 due to the uneven exhaust pulses fighting to exit the shared exhaust manifold or header collector on a bank of cylinders A flat plane crank will fire every 180* so all the exhaust pulses are even so, even if adjacent cylinders on a bank have to use a common exhaust, the pulses are even and tend to scavenge each previous exhaust cycle more efficiently especially at higher rpms and the even pulses make for a higher frequency smoother sound that do not fight each other unlike the cross plane where some of the exhaust pulses cancel and disrupt each other s tone and tend to lower the sound
The 180* headers can make a cross plane crank engine sound like a 180* crank by pairing up cylinders heed pipes that are 180* apart in exhaust cycle. The major problem with that is you have to cross from one side of the block to the other side with the primaries which is hard to do do mostly to space constraints..they tend to look like a bundle of snakes as it were
[This message has been edited by Erik (edited 10-31-2007).]
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10:42 PM
Erik Member
Posts: 5625 From: Des Moines, Iowa Registered: Jul 2002
What was done to the exhaust?? that was my second guess except I was thinking LS7 ..I've heard one on youtube with an aftermarket exhaust that sounds similar ..my Alfas sound similar but better
[This message has been edited by Erik (edited 11-01-2007).]
Originally posted by Erik: thanks I'll contact him ..hopefully he has some sound clips
Last time I saw them they were not on a vehicle, I don't think he's ever installed them. I could be wrong. They were iron though, and I can't remember if they were made from mandrel bends or just stock exhaust bends. It's been quite a while since I've visited w/him, but he was polishing his stainless welding skills at that time, working w/that paste stuff and comparing to purging w/ inert inside the pipe. If the $$$$.%s right he may be able to be coersed into making some, at least he has a template to make some more. Throws a nice bead, I'm envious of his skills.
Me . . . . I'd just like to have equal length primaries into a 3into1+2into1. On a DTC that's gonna be complicated enough, at least it's a '95.
Originally posted by ryan.hess: Put a crossover in exactly the right spot and you don't have to deal with the even-odd-odd exhaust pulses.
On a chassis dyno, under load, at the peak torque RPM measure the temps of the header pipes behind the collecters, (use one of those IR spot meters) run your crossover pipe between the two hottest spots voila! In the old days we just used some paint and watched where it burned up first while driving around the block, neighbors thought we were nuts, hard pulls in 3rd, stop, crawl under, repeat as necessary until the paint bubbled. Hard on the clutch. Norm
P.S. : May not be practical in a Fiero. A lot easier in a lifted bobtail Bronco w/ 351W (different firing order than a 302).
A Boss351 in a Fiero w/ a 'bundle o' snakes" now ur talkin! Come on Dave, there's your power train for that tubular chassis.
[This message has been edited by gt88norm (edited 11-01-2007).]
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01:00 AM
Will Member
Posts: 14280 From: Where you least expect me Registered: Jun 2000
Originally posted by Erik: Its the firing pulses ..Taking a V8 for example, a cross plane crank will fire every 90* and give you a burbling rumbling sound so common to the typical American V8 due to the uneven exhaust pulses fighting to exit the shared exhaust manifold or header collector on a bank of cylinders A flat plane crank will fire every 180* so all the exhaust pulses are even so, even if adjacent cylinders on a bank have to use a common exhaust, the pulses are even and tend to scavenge each previous exhaust cycle more efficiently especially at higher rpms and the even pulses make for a higher frequency smoother sound that do not fight each other unlike the cross plane where some of the exhaust pulses cancel and disrupt each other s tone and tend to lower the sound
This is almost completely wrong. In ANY square crank V8, there are two adjacent cylinders in each bank that are consecutive in the firing order. When these two fire, the exhaust "sees" a big pulse that makes each bank breathe like a 3 cylinder with one cylinder larger than the other two. These larger pulses interspersed with the smaller pulses give the square crank V8 its characteristic "throb". An X-pipe equally distant from each exhaust valve will interleave the pulses from each bank resulting in a smooth sound. Headers will still need non-optimal collectors, however, in order to deal with the larger pulse. Flat crank V8's fire every 90 degrees. A square crank V8 is two V4's end to end. A flat crank V8 is two inline 4's on a common crankshaft.
You are right about 180 degree headers on a flat crank engine, though.
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05:54 AM
James Bond 007 Member
Posts: 8872 From: California.U.S.A. Registered: Dec 2002
This device is interesting,it's called a Vroom Box $159.+tax it reproduces maney diffrent car sounds like Shelby Cobra,Nissan 350Z,Camaro SS,Barracuda,Pontiac GTO,Harley Davidson,Lambhorghini V12,Shelby Mustang,Stingray,Vespa Scooter.I thought this thing allso had Ferrari....my Goof. http://www.vroombox.com/vroombox/
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11:05 AM
Erik Member
Posts: 5625 From: Des Moines, Iowa Registered: Jul 2002
Originally posted by Erik: Its the firing pulses ..Taking a V8 for example, a cross plane crank will fire every 90* and give you a burbling rumbling sound so common to the typical American V8 due to the uneven exhaust pulses fighting to exit the shared exhaust manifold or header collector on a bank of cylinders A flat plane crank will fire every 180* so all the exhaust pulses are even so, even if adjacent cylinders on a bank have to use a common exhaust, the pulses are even and tend to scavenge each previous exhaust cycle more efficiently especially at higher rpms and the even pulses make for a higher frequency smoother sound that do not fight each other unlike the cross plane where some of the exhaust pulses cancel and disrupt each other s tone and tend to lower the sound
quote
Originally posted by Will:
This is almost completely wrong. In ANY square crank V8, there are two adjacent cylinders in each bank that are consecutive in the firing order. When these two fire, the exhaust "sees" a big pulse that makes each bank breathe like a 3 cylinder with one cylinder larger than the other two. These larger pulses interspersed with the smaller pulses give the square crank V8 its characteristic "throb". An X-pipe equally distant from each exhaust valve will interleave the pulses from each bank resulting in a smooth sound. Headers will still need non-optimal collectors, however, in order to deal with the larger pulse. Flat crank V8's fire every 90 degrees. A square crank V8 is two V4's end to end. A flat crank V8 is two inline 4's on a common crankshaft.
You are right about 180 degree headers on a flat crank engine, though.
Will, I am not wrong about the typical American v8 sound. I am talking about normal production American V8 engines that do not have x pipes. As mentioned "uneven exhaust pulses fighting to exit the shared exhaust manifold" do cause that "burble" as it were. I did not say that a crossplane crank does not a have 2 cylinders on a bank that do not fire consecuetively. I do agree that as you mentioned, there is large pulses and small and it is those that fight each other on a cross plane that uses a common exhaust header or manifold on each bank
Correct, a flat crank 90* V8 DOES fire every 90* when you look at it as a V8 but not on the same bank and that is what my point was as mentioned before, it only fires and exhausts 180* off from each cylinder on the same bank so that using a common header or manifold for that bank there is no conflicting pulses, they are even and thats where you get the unique sound from
[This message has been edited by Erik (edited 11-01-2007).]
Originally posted by Will: 180 degree headers do not and can not exist for a V6 because V6's have 120 degree firing intervals...
OK, point taken, . . . on the V6 in topic : two cylinders are at TDC at the same time. Cylinders 1 & 4, 2 & 5, and 3 & 6, each of those pairs fire 180* from their respective oposite. Scavenging those opposed cylinders is in effect what I'm terming to be 180* scavenging, maybe my semantics are wrong, maybe they're not, but that's what a large % of people around my parts consider to be 180* scavenging. Maybe it's 360* scavenging because of one full crank revolution, any way, I think the process is understood. It's pretty safe to say this applies to most four stroke motors with an even # of cylinders greater than 4.
Norm
[This message has been edited by gt88norm (edited 11-01-2007).]
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01:04 PM
rogergarrison Member
Posts: 49601 From: A Western Caribbean Island/ Columbus, Ohio Registered: Apr 99
My Ferrari kit with a 3.1 turbo sounded very Ferrari. Helped that redline was near 7000. Im sure some of the regs at Carlisle could attest to that. At least the 308 models. 308 V8s were almost same displacement.
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01:18 PM
Erik Member
Posts: 5625 From: Des Moines, Iowa Registered: Jul 2002
My Ferrari kit with a 3.1 turbo sounded very Ferrari. Helped that redline was near 7000. Im sure some of the regs at Carlisle could attest to that. At least the 308 models. 308 V8s were almost same displacement.
the highrpm definately helps..my 3.4 dohc starts to scream at high rpm although as mentioned before its lower in tone most likely due to the turbo mufflers and exhaust size ...real 308s have a flat crank
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03:53 PM
PFF
System Bot
Will Member
Posts: 14280 From: Where you least expect me Registered: Jun 2000
Will, I am not wrong about the typical American v8 sound. I am talking about normal production American V8 engines that do not have x pipes. As mentioned "uneven exhaust pulses fighting to exit the shared exhaust manifold" do cause that "burble" as it were. I did not say that a crossplane crank does not a have 2 cylinders on a bank that do not fire consecuetively. I do agree that as you mentioned, there is large pulses and small and it is those that fight each other on a cross plane that uses a common exhaust header or manifold on each bank
Correct, a flat crank 90* V8 DOES fire every 90* when you look at it as a V8 but not on the same bank and that is what my point was as mentioned before, it only fires and exhausts 180* off from each cylinder on the same bank so that using a common header or manifold for that bank there is no conflicting pulses, they are even and thats where you get the unique sound from
Then specify bank for bank or whole engine... An odd fire 4.3 V6 has uneven exhaust pulses, but no one likes the way it sounds. What makes the square crank V8 sound is not that the pulses are uneven per se, but that there are two consecutive pulses in each bank.
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05:47 PM
Will Member
Posts: 14280 From: Where you least expect me Registered: Jun 2000
OK, point taken, . . . on the V6 in topic : two cylinders are at TDC at the same time. Cylinders 1 & 4, 2 & 5, and 3 & 6, each of those pairs fire 180* from their respective oposite. Scavenging those opposed cylinders is in effect what I'm terming to be 180* scavenging, maybe my semantics are wrong, maybe they're not, but that's what a large % of people around my parts consider to be 180* scavenging. Maybe it's 360* scavenging because of one full crank revolution, any way, I think the process is understood. It's pretty safe to say this applies to most four stroke motors with an even # of cylinders greater than 4.
Norm
That would be 360 degree scavenging... That's an interesting way of looking at things, but I don't think it would do any good on a V6... Almost all the blow down happens early in the exhaust stroke. A 240 degree pulse interval (each bank into its own collector) is MORE than enough to prevent the tail of one pulse from overlapping the head of the next. You wouldn't gain much, if anything, by going from 2 x 240 degree collectors to 3 x 360 collectors and then collecting those into one... the plumbing would also be very complicated because each of the 2 way collectors would have a pipe from each bank.
For the aforementioned reasons of pulse interval, 180 degree headers are worth it on a V8, but I don't think such extremes gain anything on a 6.
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05:55 PM
F-I-E-R-O Member
Posts: 8410 From: Endwell, NY Registered: Jan 2005
I started reading this and started to get confused. After popping a vessel, I hit my back button and got more confused about all the new topics that I hadn't seen yet. Looked up and realized I was in Tech.
This is a really neat thread, and I always learn something (albeit just a little at a time) when I check this side of the forum out. Thanks for reminding me that I need to go out and hug my engine, then look for something to change...
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06:05 PM
Erik Member
Posts: 5625 From: Des Moines, Iowa Registered: Jul 2002
Then specify bank for bank or whole engine... An odd fire 4.3 V6 has uneven exhaust pulses, but no one likes the way it sounds. What makes the square crank V8 sound is not that the pulses are uneven per se, but that there are two consecutive pulses in each bank.
I did .... A flat plane crank will fire every 180* so all the exhaust pulses are even so, even if adjacent cylinders ON A BANK have to use a common exhaust ..I understand the confusion and have clarified my point
if the pulses were even on a crossplane V8 then it would not have that characteristic burble
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07:09 PM
Erik Member
Posts: 5625 From: Des Moines, Iowa Registered: Jul 2002
While the tech side I am at a loss over, the actual production of said tech, i.e., the ferrari sound, should you find a way Erik, It would definately conclude my future engine swap woes!.....
By the way, what exactly is true dual exhaust?
edit: What happened with the actual ferrari engine, or was that not you who bought one?
------------------ Me, I sell engines, the cars are for free, I need something to crate the engines in.... Enzo Ferrari....
Today they are called garage's, yesterday, they were stable's! Eric Jacobsen....
[This message has been edited by pavo_roddy (edited 11-01-2007).]
Originally posted by Will:3 x 360 collectors and then collecting those into one... the plumbing would also be very complicated because each of the 2 way collectors would have a pipe from each bank.
For the aforementioned reasons of pulse interval, 180 degree headers are worth it on a V8, but I don't think such extremes gain anything on a 6.
I have seen an example, it was an heroic effort on the part of the builder. An extreme effort, how it sounds, or performs I know not! Like posted in the thread that I believe to be the precursor to this one . . . "I'd settle for equal length primary 3X1X2X1" . . . equally spaced exhaust pulses would be fine for my needs.
Norm
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11:26 PM
Nov 2nd, 2007
Austrian Import Member
Posts: 3919 From: Monterey, CA Registered: Feb 2007
Originally posted by Fierobsessed: You have to give it up to Nissan though, their VQ35, with its exhaust system has got a really unique and pleasant sound, slightly resembling a Ferrari, but notably different too. I don't know if it is the engine, or that really overengineered length of pipe and muffler doing that to the sound.
Yea, I love that sound. To the point that every once in a while I dream about using the fwd Nissan Altima VQ35 engine. Then I realize that I'd probably be waaaay over my head.
I think the sound is the engine, not necessarily the exhaust system. The reason I'm saying that is because when I researched cat-back exhaust systems for my Mazda, I stumbled across a websites that compare about 8 different cat-back exhaust systems on a Nissan 350z. Most (if not all) retained that stock sound. The pitch changed slightly, or the volume, but the sound remained the same otherwise.
quote
Originally posted by FieroWannaBe: I think that the GT40s had 180 degree headers, its doable in a fiero i guess.
Wow, that makes me dizzy just looking at it. This reminds me of the "rats nest" in a Mazda Rx-7 twin turbo. Some great welding though.. The Jet-hot ceramic coating looks great too. Shiney..
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02:13 AM
Will Member
Posts: 14280 From: Where you least expect me Registered: Jun 2000
On a chassis dyno, under load, at the peak torque RPM measure the temps of the header pipes behind the collecters, (use one of those IR spot meters) run your crossover pipe between the two hottest spots voila!
The problem with this in a Fiero is that the two hot spots A) probably won't be right next to each other (transverse layout) B) probably won't be equally distant from each bank's valves due to different routing and different numbers of bends.
Any more info on why this method is supposed to work?
