![]() |
|
|
|
|||||
|
" hell by your crank theory a air-cooled VW 1600 should sound like a Ferrari... "
Actually, no. A VW fires two cylinders on one side of the engine, then fires two cylinders on the other side of the engine. VW numbers banks of cylinders, like Ford. Right side front, #1, right side rear, #2, left side front #3, left side rear #4. VW firing order, 1, 4, 3, 2. Or starting with #4, 4, 3, 2, 1. two left, two right. Because a Ferrari has 8 cylinders on a 90 degree V, with a 180 degree crankshaft, it has to alternate each bank to fire every 90 degrees of crankshaft rotation. |
|
|||||
|
danielc a 4 cylinder,low compression,air cooled vw boxer engine with ohv sounds nothing at all like a 11:1,dohc,water cooled,fuel injected,boxer...even with 4 into 1 muffler with 2 tail pipes
|
|
|||||
|
Bogie, thanks.
To all else, to quote the bowl of petunias "oh no not a again" |
|
|||||
|
"danielc a 4 cylinder,low compression,air cooled vw boxer engine with ohv sounds nothing at all like a 11:1,dohc,water cooled,fuel injected,boxer...even with 4 into 1 muffler with 2 tail pipes "
I never said it did. AP72 said that a VW engine should sound like a Ferrari, based on my comment about the Ferrari getting its sound from the 180 degree crank it has. |
|
|||||
|
Quote:
|
|
||||
|
Really OMG im wrong.
Ferrari spends millions of dollars to tune there exhuast. This is a well known fact. One quick google search will clear that up. Your exhuast pulse theroy is great theroy. But a 8 into 1 that comes on most passenger cars puts a pretty big dent in it. Most of them sounds the same v6 to v12 not just the v8. The exhuast note is very important. I used to help a guy that sold ferrari exhaust systems. Must have seen two hundred of them. Cant remeber one with an x pipe. Usally just two straight cross overs. But what do i know i didnt even use capital letters. 4-7 swap have you herd of it. This does change the sound of the engine lots of ppl on youtube have videos. |
|
|||||
|
Why don't you tell that to Reeves Callaway, perhaps your experience surpasses his as well?
Maserati has used ferrari engines since they were bought out by fiat. They use a cross plane crankshaft instead of a flat plane. They also use tri-y headers factory and an x pipe further back toward the mufflers. I worked on these cars for 10 years. I know what they have. You may have sold them but that means nothing. Have you ever had a flat 12 ferrari motor all tore apart? I doubt it. Oh and just so you can see for yourself.... Ferrari/Maserati engine - Wikipedia, the free encyclopedia http://cars-database.com/data_images...rati-v8-03.jpg a similar snarl that the Corsa gives the Domestic V8 A New V8 Engine Powers the Maserati GranTurismo S - ATZ online there is your x pipe guy... 08 Maserati Gran Turismo 4.2 complete exhaust mufflers silencers | eBay The illustration shows Exh mani as a 4 into 1 design, shorty, primaries appear to be equal length. X pipe is a ways downstream..... http://www.maseratispares.com/1998-h...es/492_023.jpg same 136 engine only the tipo f136 has a flat plane. What they tell you on google is marketing bull**** about them tuning the mufflers. There is so little time put into that its ridiculous. There is plenty of time spent on the exhaust manifolds (including collectors) as well as i am sure the placement of the x pipe. also when I said 4 cyl (at ap72) i should have said a inline 4 cylinder. flat motors or "boxers" have a different sound all on their own. part of why a subaru and the vw motor you are talking about sound like **** (to be blunt) is the power design of the exhaust manifolds. the porsche motors have done significantly better in their manifold design for both performance and sound. |
|
|||||
|
the alfa uses the same cross plane motor as the maserati. very similar. I am sure the slight differences of video quality and the bends in the exhaust that differ between the two can attest to the very slight difference in sound.- still sounds like a domestic with corsa's and an x pipe.
|
|
|||||
|
How about we turn to something that takes a traditional 90 degree motor (with itbs, dohc heads, and di) that uses tri-y headers and an x pipe factory.
The s65 bmw motor is a lovely motor. sounds like a small block chev on the dyno to me, buts its the bmw m3 s65 v8. compare that to this full exhaust system by ipe f1 https://www.youtube.com/watch?v=SbT0IqFIfnc compare that to this and lastly compare those to this there really has to be more to it than the natural sound of the motor... i agree that it is more than JUST one thing. I never said it was JUST one thing that makes the sound of the motor. "The crank pin offset is 90°, and for design reasons, a cylinder firing order of 1-5-4-8-7-2-6-3 was chosen for the S65, instead of the typical 1-5-4-8-6-3-7-2 firing order more commonly employed in other BMW V8 engines." if you can make some sense of that- its odd "Cylinder numbering is 1 through 4 on passenger (right) side and 5 through 8 on driver (left) side. numbers 1 and 5 are at the front, 4 and 8 are at the rear." BMW Engine Firing Order and Cylinder Location (Bank-1, Bank-2), 4-cylinder, 6-cylinder, V8, V12 | Bavarian Autosport Blog Apparently, the fireing order is the same as the BMW Sauber F1 team v8. check out this s65 header. looks like a tri-y to me, what do you think? http://img364.imageshack.us/img364/3289/dscn0632nb7.jpg Exhaust System Technology: Science and Implementation of High Performance Exhaust Systems http://www.billswebspace.com/DinanE9...signReview.pdf https://www.youtube.com/watch?v=J9u6jI3lRCw The x pipe from the above video. http://maxcdn.nexternal.com/aaw/images/Large252.jpg I think the only reason that the ipe f1 exhaust is higher has to be that x pipe design. which is shown in the following link http://i244.photobucket.com/albums/g...917_221533.jpg http://i.imgur.com/batEA.jpg (not to scale dims) Note the taper of the x pipe and the hole that makes the air pass through a smaller opening on two ends. If you look very close at the x pipe design, its ALMOST as if its two x pipes in one. http://i17.photobucket.com/albums/b8...imsactual2.jpg |
|
|||||
|
No one thing to consider is the are resonators that cancel out particular noise. this is what Corsa mufflers do. The have chambers in the mufflers (which is more like an instrument than a traditional muffler) that are helmholtz resonators that are VERY small. They shoot for 3 particular resonate frequencies to cancel out. Now one thing about frequency is that it peaks, there is a range at the peak. The range will depend on many things and without actual testing it is not possible to know the range with math (that i am aware of to date).
Helmholtz resonance - Wikipedia, the free encyclopedia In use on an exhaust system Capped Helmholtz chamber (Drone Eliminator) Now if you actually understand the above link you will see that they are utilizing a Helmholtz Resonator and then packing around it with fiberglass to bring down the vibration(vibration of any kind will bring the volume of the devise up- so this muffles it). the purpous of a "muffler" is to MUFFLE sound not change the actual tone. the corsa i wouldn't even call a muffler per say. I would say it is more similar to the dr. gas freq mod, but a better design. FreqMod Mufflers corsa cut away http://s938.beta.photobucket.com/use...tml?sort=3&o=0 I should also note that ferrari motors that have a 180 crankshaft do not require an x pipe to merge the exhaust pules efficiently because they already do that naturally with the design of the crankshaft (and firing order of course that goes along with it). Last edited by blight; 11-29-2012 at 03:30 AM. |
|
|||||
|
So as you can see. There is more to it than you know. It sounds to me that Bogie is familiar with all the things That I just posted.
I am not trying to be a jerk but when people claim they "know" something that they do not it ticks me off. I have spent the last 8 months or more studying this subject. Using physics, experimentation, contacting multiple "big names" (vizard, and callaway as an example), and many other forms of research. I am not saying this is the end all of the subject. There is plenty more~ that I will not waste my time posting. I don't post that often for this particular reason. it would be a waste of my time to try to explain every little aspect that i found along the way. Bogie answered my question to the best of his ability with out the bologna. As far as I see it this is the end of the subject to me seeing that my question was answered. |
|
|||||
|
oh as for the 180 header. I suppose I should post this- one of many, videos of a sbc with 180s sounding exotic as they do. The kelmarks, grant gts, and many other cars use these headers as well (gt40s too).
I did forget to mention that (as far as i know) all inline 4s use a flat plane crankshaft. |
|
|||||
|
I still think there is something to the 180 crankshaft in a Ferarri. It alternates cylinder banks firing evenly.
A 90 degree V-8 engine with a 90 degree crankshaft fires banks in this order, (Ford) Right, left, right, right, left, right, left, left., or right, right, left, right, left, left, right, left. I am a little familiar with a Helmholtz resonator. I built two Subwoofers for live sound, that are ported 14 cubic foot boxes, with two Electro-voice DL-18-W speakers in them. These boxes have a flat frequency response down to 34 Hertz, and drop off as 12 DB, per octave below that. I run the crossover frequency about 150 HZ. |
|
||||||
|
Quote:
nice post number ..
|
|
|
| Recent Engine posts with photos |
| Currently Active Users Viewing This Thread: 1 (0 members and 1 guests) | |
| Thread Tools | |
|
|
Similar Threads
|
||||
| Thread | Thread Starter | Forum | Replies | Last Post |
| does a carb spacer make a difference? | jerryvarnell | Hotrodding Basics | 6 | 08-06-2011 01:18 PM |
| Make that Exhaust Pipe Look Good | Grasor | Engine | 3 | 04-03-2010 07:11 AM |
| Do ROLLER rockers REALLY make a difference in HP. | phillips63 | Engine | 17 | 12-18-2007 06:24 PM |
| Good Grounding can make a difference | ep33510 | Electrical | 2 | 12-07-2005 07:42 PM |
| Headers and the difference they make | calimstng66 | Engine | 2 | 01-05-2005 06:06 PM |