Formula for the ultimate 928 Exhaust note?
12-21-2006, 04:02 PM
#16
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Correct..."Evrything will have an effect on the sound size of pipe, bends, placement of cats, muffler, tips..." What makes the 928 engine sound "different" is the EXHAUST system because the firing order is the same as several American V-8 engines. So the sound coming out of the engine is much the same what the pipes do with it is a matter of tuning....for sound.
12-21-2006, 04:07 PM
#17
Drifting
Hey Jim, even cams have a lot to do with the sound of the exhaust. S4's are considerably quieter using our X and an RMB than 85-86's and GT's... everything else being equal. 4 valve engines sound different than 2 valve ones also, 2 valve are bassier at low rpm, quieter at high rpm with the same exhaust. IMHO...
12-21-2006, 04:35 PM
#18
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Jim, interesting bit of info. I've heard that before, but for the first time I tried to map it out. On the surface it looks different, even taking the different cylinder numbering into account:
928:
1-3-7-2-6-5-4-8
1-2-3-4
<-F
5-6-7-8
Chrysler:
1-8-4-3-6-5-7-2
2-4-6-8
<-F
1-3-5-7
If you draw arrows between cylinders to indicate firing order it doesn't seem to match up. If you flip the Chrysler diagram upside down, the pattern of arrows drawn between cylinders does match up:
8-6-4-2
F->
7-5-3-1
928:
1-3-7-2-6-5-4-8
1-2-3-4
<-F
5-6-7-8
Chrysler:
1-8-4-3-6-5-7-2
2-4-6-8
<-F
1-3-5-7
If you draw arrows between cylinders to indicate firing order it doesn't seem to match up. If you flip the Chrysler diagram upside down, the pattern of arrows drawn between cylinders does match up:
8-6-4-2
F->
7-5-3-1
12-21-2006, 05:05 PM
#19
Nordschleife Master
Originally Posted by Jim bailey - 928 International
Since "Music" is typically just repeated patterns of random noise most people LIKE such things.....
and now you know what I think about music !
and now you know what I think about music !Visit a few Ford or Chevy sites that have sound or video clips to pick the muffler sound you like. I went to www.dogpile.com and typed muffler sounds and selected an audio search.
http://www.ls1sounds.com/mufflex.htm many to choose from a couple examples.
http://www.ls1sounds.com/Flowmaster/...er_stockTA.MPG
http://www.ls1sounds.com/mufflex/muf...-manifolds.wma
Lots more sites, the LS1 stuff just turned up first.
http://www.youtube.com/watch?v=Z_sBdtcSh2c
http://media.putfile.com/Spintech-Pr...ff-road-X-Pipe
Doesn't cam timing also effect exhaust sound? The 928 certainly seems unique to me.
Some 928 sounds
http://www.928sg.com/928sg.wav
http://members.rennlist.com/bigdave/my928.wav
http://www.landsharkoz.com/mmedia/928s4.wav
12-21-2006, 05:36 PM
#20
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IMO, there's no better sound than a jet taxiing down the runway - the type of sound that comes from a big turbocharger. Straight pipe it w/ 3.5-4" after the turbo and you'll hear that turbine whine from blocks away - off boost! On boost it will roar like a v8 jet.
12-21-2006, 05:48 PM
#21
Rennlist Member
Originally Posted by atb
I'm searching for the ultimate exhaust for my stroker project.
Ultimate to me does not mean ultimate power, I think I'm going to have plenty of that when the motor is done. I want the ultimate sounding exhaust note, and I'm willing to pay the cost of some additional horsepower in my quest.
I've heard a lot of different configurations, all displacements, N/A, S/C's and turbo'd.
Out of all the one's I've heard, one stands out above the rest.
Dennis Wilson's S4 with the full DEVEK exhaust. It has the DEVEK II headers, random cats, going into a single 3" pipe with a single flow master.
This 928 sounded very non-928, actually very non-V8. It had more of a ferrari V-12 (tinny) high pitched tone. Reminded me of a two stroke dirt bike with a sizeable stinger on it. The exhaust actually sounded a little corked up, but it was awesome.
1) Anyone care to venture (not the "V" word, but close) what part of the exhaust gave it this quality?
2) Any NorCal folks heard this combination on any local cars down there?
Other than my 928 Intl headers, I'm starting with a blank slate.
Ultimate to me does not mean ultimate power, I think I'm going to have plenty of that when the motor is done. I want the ultimate sounding exhaust note, and I'm willing to pay the cost of some additional horsepower in my quest.
I've heard a lot of different configurations, all displacements, N/A, S/C's and turbo'd.
Out of all the one's I've heard, one stands out above the rest.
Dennis Wilson's S4 with the full DEVEK exhaust. It has the DEVEK II headers, random cats, going into a single 3" pipe with a single flow master.
This 928 sounded very non-928, actually very non-V8. It had more of a ferrari V-12 (tinny) high pitched tone. Reminded me of a two stroke dirt bike with a sizeable stinger on it. The exhaust actually sounded a little corked up, but it was awesome.
1) Anyone care to venture (not the "V" word, but close) what part of the exhaust gave it this quality?
2) Any NorCal folks heard this combination on any local cars down there?
Other than my 928 Intl headers, I'm starting with a blank slate.
12-21-2006, 05:48 PM
#22
Drifting
I think my '86 sounds pretty darn incredible. It has that exotic, smooth sound above 4000 or so and a V8 burble/warble (I don't think that's a word, but that's what it sounds like to me) at low RPMs. It might have something to do with the aeroturbine...? I have a stock '86 5.0, with a full stainless exhaust- y-pipe to 3.5" tubing with a borla XR-1 race muffler right after the merge, then an Aeroturbine "muffler" (not much of a muffler) at the very back of the exhaust. Here is a picture before I put the Borla on (too loud at first, pretty much open exhaust). The sound is awesome, like a mix between a 928 with a RMB and a Ferrari 355.
12-21-2006, 06:02 PM
#23
Race Director
Originally Posted by Richard S
My S4 has Devek Level II headers, into high flow cats, merging into single 3" pipe, then 2 Borla's in-line. Not sure of which Borla's though. Sounds awesome. Dennis Kao has this set-up, minus the cats, and is quite a bit louder. The cats take just enough of the edge off. It "Barks" at start-up, then settles into a throaty growl. Open her up, and it becomes a mean snarl. Tons of compliments at DE days. Very liveable for everyday driving, which is VERY important for me.
Rich
Rich
12-21-2006, 06:40 PM
#24
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Dave like I said the firing of two cylinders on the same bank next to each other is what gives the normal V-8 a it's distintive sound with dual exhaust pipes. Sure things like camtiming number valves etc bore stroke all have some influence on the sound BUT the pattern of the explosions is always much the same on any V-8 unless it runs a flat crankshaft and is truely ran as two 4 cylinder engines My daughters 308 just never sounded GOOD to me I kept looking in the mirror for the two Fiats chasing me
12-21-2006, 08:40 PM
#25
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Originally Posted by danglerb
Jim have you listened to some Rap music? Its like poetry.
Visit a few Ford or Chevy sites that have sound or video clips to pick the muffler sound you like. I went to www.dogpile.com and typed muffler sounds and selected an audio search.
http://www.ls1sounds.com/mufflex.htm many to choose from a couple examples.
http://www.ls1sounds.com/Flowmaster/...er_stockTA.MPG
http://www.ls1sounds.com/mufflex/muf...-manifolds.wma
Lots more sites, the LS1 stuff just turned up first.
http://www.youtube.com/watch?v=Z_sBdtcSh2c
http://media.putfile.com/Spintech-Pr...ff-road-X-Pipe
Doesn't cam timing also effect exhaust sound? The 928 certainly seems unique to me.
Some 928 sounds
http://www.928sg.com/928sg.wav
http://members.rennlist.com/bigdave/my928.wav
http://www.landsharkoz.com/mmedia/928s4.wav
Visit a few Ford or Chevy sites that have sound or video clips to pick the muffler sound you like. I went to www.dogpile.com and typed muffler sounds and selected an audio search.
http://www.ls1sounds.com/mufflex.htm many to choose from a couple examples.
http://www.ls1sounds.com/Flowmaster/...er_stockTA.MPG
http://www.ls1sounds.com/mufflex/muf...-manifolds.wma
Lots more sites, the LS1 stuff just turned up first.
http://www.youtube.com/watch?v=Z_sBdtcSh2c
http://media.putfile.com/Spintech-Pr...ff-road-X-Pipe
Doesn't cam timing also effect exhaust sound? The 928 certainly seems unique to me.
Some 928 sounds
http://www.928sg.com/928sg.wav
http://members.rennlist.com/bigdave/my928.wav
http://www.landsharkoz.com/mmedia/928s4.wav
H2
12-21-2006, 10:26 PM
#26
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Tim Dey's Beast sounds awfully awesome to me. Find out what he has. It's a stroker too. I think it's a full DEVEK but into large duals. I can tell you it sounded pretty awesome passing me at 165.
12-21-2006, 10:31 PM
#27
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I have the Devek Level II headers, looong Y-pipe, into 3.5" single pipe w/ two Borla XR-1's. You can check out any of my vids to hear what it sounds like.
That tinny sound you hear is definitely the headers. The only analogy I can come up with is the sound of raindrops on a metal garbage can lid - plink, plink, plink (headers at low rpm). With enough raindrops, the lid starts to make a ringing noise, which is sort of like that ringing exhaust note you hear at high rpm w/ headers.
I've run different configs over the years due to the sound restrictions at Laguna Seca.
Hope this helps you on your quest.
That tinny sound you hear is definitely the headers. The only analogy I can come up with is the sound of raindrops on a metal garbage can lid - plink, plink, plink (headers at low rpm). With enough raindrops, the lid starts to make a ringing noise, which is sort of like that ringing exhaust note you hear at high rpm w/ headers.
I've run different configs over the years due to the sound restrictions at Laguna Seca.
- The longer Y-pipe (supposed to make more power) definitely changed the sound to a lower pitch.
- Swapping out the Random Tech cats for the 2nd Borla made it quieter and less raspy.
- Swapping out a shorty XR-1 for the regular length XR-1 made it quieter still. This made more of a difference volume-wise than changing over from cats
- I've also run open headers (not really on purpose) and found that the Borlas don't really change the tone, just the volume.
Hope this helps you on your quest.
12-22-2006, 03:22 AM
#28
Nordschleife Master
Bunch more clips
http://www.mustangexhaust.com/forums/soundclips.php
After a few sites you start to identify the characteristic sound of the muffler independent of the car.
Aerochamber is nice, but I think its too loud.
Magnaflow is what I am thinking of going with.
http://www.mustangexhaust.com/forums/soundclips.php
After a few sites you start to identify the characteristic sound of the muffler independent of the car.
Aerochamber is nice, but I think its too loud.
Magnaflow is what I am thinking of going with.
12-22-2006, 11:55 AM
#29
Race Director
Originally Posted by Bill Ball
Tim Dey's Beast sounds awfully awesome to me. Find out what he has. It's a stroker too. I think it's a full DEVEK but into large duals. I can tell you it sounded pretty awesome passing me at 165.
12-22-2006, 12:02 PM
#30
Race Director
Originally Posted by Bill Ball
Tim Dey's Beast sounds awfully awesome to me. Find out what he has. It's a stroker too. I think it's a full DEVEK but into large duals. I can tell you it sounded pretty awesome passing me at 165.
One thing I found interesting is how much the tone changes depending on the AFR. I believe that this is what people tune in to when "tuning by ear".