Sound deadening..... (kind of long).....
08-22-2002, 05:08 PM
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Sound deadening..... (kind of long).....
I've been thinking a lot about ways to lessen the interior noise level of my 951- it's just a little too noisy at crusing levels (~80mph). Enough that it can be difficult to hear the stereo clearly w/out having to turn it up to blaring levels....
I'm planning to do underhood insulation of some sort- what about the reflective metallic types? Anyone know if they really reflect the heat back onto the engine causing it to be hotter? I don't want it if that's the case- I want something specifically to muffle the noise...
What about spraying the inner hatch area w/some type of textured paint, like pick 'em up truck bed liner or something? Would that help? Assuming it wouldn't just a make a complete mess that is... I was thinking about trying to tack down some thin carpet underneath the hatch carpet- adding it to every bit of exposed metal and maybe trying to use something to flatten out the cubby holes, then carpeting over that, so they would be more useable- albeit smaller- storage bins- the flaps of the regular hatch carpet would still have to be lifted to get to them...
Or, covering the metal in the hatch area w/some type of neoprene or Dyna Mat?
Other places- the inner doors and inner side panels (where rear speakers reside)...
The rear seat area- I'm removing mine, and either replacing it w/968 Cab cargo tray or trying to build something myself- so I'd have to line it w/something first...
Replacing window, door, and maybe even hatch seals...
New muffler, maybe w/two free flow cats and or a resonator welded into a ~2.5" - 3.0" pipe or something- wrapping all the exhaust w/insulated heat wrap? I plan to do an engine rebuild eventually, and could get to all the difficult areas then- maybe extreme...
Would any or all of this be a waste of time and/or $? I'm looking for best bang for the buck... One of the biggest probs w/these cars is that they're hatch backs. I want my car to be quieter, like a BMW 540i or something, but don't want a 4000lb car- I know that other advantages the Bimmers have is their multi-link susp, etc...
Any advice? Has anyone tried or considered anything for theirs? Don't misunderstand me- I don't think these cars are Nascar loud or anything, but I'd just like to get the interior levels down a small amount w/out adding 400lbs worth of extra panels and 4" thick bullet proof glass, etc in the process....
Any ideas on materials to use that might be light weight and still muffle sound well- for the hatch deck and to stuff side panels with, etc?
Any input would be appreciated...
Thanks,
Robby
I'm planning to do underhood insulation of some sort- what about the reflective metallic types? Anyone know if they really reflect the heat back onto the engine causing it to be hotter? I don't want it if that's the case- I want something specifically to muffle the noise...
What about spraying the inner hatch area w/some type of textured paint, like pick 'em up truck bed liner or something? Would that help? Assuming it wouldn't just a make a complete mess that is... I was thinking about trying to tack down some thin carpet underneath the hatch carpet- adding it to every bit of exposed metal and maybe trying to use something to flatten out the cubby holes, then carpeting over that, so they would be more useable- albeit smaller- storage bins- the flaps of the regular hatch carpet would still have to be lifted to get to them...
Or, covering the metal in the hatch area w/some type of neoprene or Dyna Mat?
Other places- the inner doors and inner side panels (where rear speakers reside)...
The rear seat area- I'm removing mine, and either replacing it w/968 Cab cargo tray or trying to build something myself- so I'd have to line it w/something first...
Replacing window, door, and maybe even hatch seals...
New muffler, maybe w/two free flow cats and or a resonator welded into a ~2.5" - 3.0" pipe or something- wrapping all the exhaust w/insulated heat wrap? I plan to do an engine rebuild eventually, and could get to all the difficult areas then- maybe extreme...
Would any or all of this be a waste of time and/or $? I'm looking for best bang for the buck... One of the biggest probs w/these cars is that they're hatch backs. I want my car to be quieter, like a BMW 540i or something, but don't want a 4000lb car- I know that other advantages the Bimmers have is their multi-link susp, etc...
Any advice? Has anyone tried or considered anything for theirs? Don't misunderstand me- I don't think these cars are Nascar loud or anything, but I'd just like to get the interior levels down a small amount w/out adding 400lbs worth of extra panels and 4" thick bullet proof glass, etc in the process....
Any ideas on materials to use that might be light weight and still muffle sound well- for the hatch deck and to stuff side panels with, etc?
Any input would be appreciated...
Thanks,
Robby
08-22-2002, 05:39 PM
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BTW- with this post, I should now officially become- drum roll please.... A GURU!!!!!
WOOO HOOO! Cheers all around, applause, throw $, etc...
Of course, now I feel like a REAL TOOL, since I'm still not an official Rennlist member- I'd LOVE to do something about it right now, but am jobless as of several weeks ago- hopefully only temporarily...
Anyway- I hereby promise to get a Rennlist membership when I get a real job...
<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
And to the many of you out in cyberspace who have collectively helped me along, all this time- thank you...
And to John & Jen, ,and the other's who make this list possible- THANK YOU, THANK YOU, THANK YOU!!!! I hope to be able to help repay you one of these days...
<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
WOOO HOOO! Cheers all around, applause, throw $, etc...
Of course, now I feel like a REAL TOOL, since I'm still not an official Rennlist member- I'd LOVE to do something about it right now, but am jobless as of several weeks ago- hopefully only temporarily...
Anyway- I hereby promise to get a Rennlist membership when I get a real job...
<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
And to the many of you out in cyberspace who have collectively helped me along, all this time- thank you...
And to John & Jen, ,and the other's who make this list possible- THANK YOU, THANK YOU, THANK YOU!!!! I hope to be able to help repay you one of these days...
<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
09-01-2004, 06:48 PM
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As a new 944 owner, I'm finding the interior sound a little on the loud side, and would like to try and quiet it down a little. Has anyone found any effective means to accomplish this?
BTW, this is a great site. I've learned so much so quickly thanks to the collective experiences of you all.
Dave
84 944
BTW, this is a great site. I've learned so much so quickly thanks to the collective experiences of you all.
Dave
84 944
09-01-2004, 07:00 PM
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A few suggestions -
1) new foam under the console. You'd be amazed how much noise comes up through the shifter. Chances are your console/shifter foam is deteriorated
2) The factory underhood pad, not the cheap aluminum foil stuff. If you ever go into a recording studio, they have foam spikes and or waffle patterns on the wall that look like larger versions of the factory underhood foam. The foam absorbs the sound, and by multiplying the number of surfaces for the sound to hit, more is absorbed, and what is reflected has a better chance of being immediately absorbed by another surface
3) how is the sound/heat insulation around your bellhousing?
4) Exhaust in good shape?
5) Get new rubber hangers for your exhaust system
6) Replace other rubber parts on the car that have aged. They were all absorbing vibration and are now transmitting it through the body. The body turns vibrations into sound like a speaker.
7) How is your transmission mount(s)? When they harden that's a lot of noise, esp. from gearbox.
8) There are a lot of noisy tires on the market. . . . maybe yours?
9) Do I need to mention motor mounts?
10) Look throughout the body where they had foam or sound deadening material from the factory - example, rear quarter panels. If the stuff is gone or hardened, replace it. The dense pads they stuck inside the rear quarters might be simlar stuff to dynamat (might be cheaper than dynamat, too! - damn that stuff's expensive). Replace any missing or torn up foam. Reglue where it was originally...
11) How is the big heavy mat under the rear cargo carpeting? If it is disintegrated (especially the dense black top mat part), that will contribute somewhat to noise.
Okay, those are some of my suggestions. Hope this helps..
Cheers,
Tony
1) new foam under the console. You'd be amazed how much noise comes up through the shifter. Chances are your console/shifter foam is deteriorated
2) The factory underhood pad, not the cheap aluminum foil stuff. If you ever go into a recording studio, they have foam spikes and or waffle patterns on the wall that look like larger versions of the factory underhood foam. The foam absorbs the sound, and by multiplying the number of surfaces for the sound to hit, more is absorbed, and what is reflected has a better chance of being immediately absorbed by another surface
3) how is the sound/heat insulation around your bellhousing?
4) Exhaust in good shape?
5) Get new rubber hangers for your exhaust system
6) Replace other rubber parts on the car that have aged. They were all absorbing vibration and are now transmitting it through the body. The body turns vibrations into sound like a speaker.
7) How is your transmission mount(s)? When they harden that's a lot of noise, esp. from gearbox.
8) There are a lot of noisy tires on the market. . . . maybe yours?
9) Do I need to mention motor mounts?
10) Look throughout the body where they had foam or sound deadening material from the factory - example, rear quarter panels. If the stuff is gone or hardened, replace it. The dense pads they stuck inside the rear quarters might be simlar stuff to dynamat (might be cheaper than dynamat, too! - damn that stuff's expensive). Replace any missing or torn up foam. Reglue where it was originally...
11) How is the big heavy mat under the rear cargo carpeting? If it is disintegrated (especially the dense black top mat part), that will contribute somewhat to noise.
Okay, those are some of my suggestions. Hope this helps..
Cheers,
Tony
09-02-2004, 12:27 AM
#6
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"new foam under the console. You'd be amazed how much noise comes up through the shifter. Chances are your console/shifter foam is deteriorated
"
That is so true.
I replaced the gear lever bushing and accidently took out a VERY small piece of foam. Man, not i can hear the clutch and the shifter makes an awful noise.
I am planing on going to a music store and get some (little) sound deadening foam and just place it under there.
As far as the hood insulation is concerned. I would NOT go for the factory OEM style (There is a reason why later 944's were not equipped with them, probably due to safety reasons).
The reflective type is good for protecting paint and it's slightly thicker than the OEM type. So, less sound, it is even fire resistant.
"
That is so true.
I replaced the gear lever bushing and accidently took out a VERY small piece of foam. Man, not i can hear the clutch and the shifter makes an awful noise.
I am planing on going to a music store and get some (little) sound deadening foam and just place it under there.
As far as the hood insulation is concerned. I would NOT go for the factory OEM style (There is a reason why later 944's were not equipped with them, probably due to safety reasons).
The reflective type is good for protecting paint and it's slightly thicker than the OEM type. So, less sound, it is even fire resistant.
09-02-2004, 02:11 AM
#7
Hi,
I've got no experience with insulating under the hood, but I do have some with the interior. I'm a bit of an audio nut (both home and mobile) - some my comments below are theoretical but many are from practical experience doing some of my own car audio projects.
I just acquired a 968 (1994 Guards Red, Coupe) that has the chip, high performance exhaust and some big 265/30 tires in the rear and I find it too loud for my taste. I will be embarking on a serious sound deadening project in the next couple days...
First of all, sound deadening encompasses several things. There is the absorption that someone mentioned above which is basically having absorbent materials in the path/vicinity of the sound. This absorbant material intercepts the sound and 'holds' it and prevents it from echoing all around. Having multiple angles (rough finish as opposed to smooth is a start) will also help the sound deadening by dispersing the sound waves and giving additioanl surface area to absorb the sound.
In adition to absorption there is also the concept of blocking sound so that it simply can't enter the area you want to be quiet. Think of weather stripping, or think of shutting a window. Now you hear it now you don't... The seals around the windows and doors stop the sound from finding its way into the space. Once it has entered your only hope it so have lots of absorbent or turn up the stereo. On a car there are lots of little openings and channels for sound to come through and your job is to plug as many of them as possible.
You must think in terms of both sealing out noise and absorbing it. Your carpet is of course a natural absorber of sound while the glass is simply going to reflect everything back at you. The weather seals are attempting to stop sound from entering, but that missing or tattered insulation or that worn weather strip is letting sound leak in.
The fact that the car is a hatch back creates two problems - there is a large area that needs to be effectively sealed around the perimeter of the glass and of course glass is reflective - low in absorption. On top of all that, hatch backs and vans have another problem - the area directly above the rear wheels/suspension is in the interior of the car as opposed to being behind the back seat as they are in a sedan. This requires some extra attention.
So basically you want to do three things.
1. Seal out noise before it can enter the car
2. Absorb sound that does enter
3. Nail down (figuratively) anything that might vibrate or resonate and in turn add to the overall noise level.
Alternatively you can
1. Have an awesomely loud stereo, or
2. Travel with an extremely alluring member opposite sex so that you are continually distracted from the noise.
Products like Dynamat or RAAM mat or FatMat attempt to combine multiple attributes. First of all they are designed to stick to the surface they are applied to. This 'damps' the resonance/sound of that particular panel and also attemps to seal out any sound from leaking in. They are also typically multiple layers which also helps deaden sound. Multiple layers of different materials helps because different materials resonate at different frequencies and if you can get them in close contact the vibrations will cancel each other. Imagine knocking on a piece of metal. Now imagine gluing a thin piece of rubber to that piece of metal and knocking again. Less 'ringing' and less overall sound.
Your idea of trying to capture some of the sound under the hood is a good one, but before going down that road, give your car a really careful listen. When is the noise most offensive and where does the noise seem to be coming from? If its motor noise coming from the area in front of your feet then some combination of under hood instulation and some type of dampener on the firewall/floor might do it. If the sound is coming more from wind noise that is different and if it is exhaust note then that is something else again.
Also note that low notes/sounds can be tougher to erraticate than high frequencies. The ear is very sensitive directionally to high frequencies and you can pinpoint those easily and hopefully stamp them out at the source. Low frequencies tend to be "omni directional" (they seem to come from anywhere and everywhere) and they also tend to excite resonances in other materials. This omni directional thing is why you can use one subwoofer instead of two. The ear can't really distinguish the stereo effect at really low frequencies.
So, having said all that here is what I'm planning to do on my car and in roughly this order.
1. Take out the front seats, center console and carpet and cover the entire floor of the car with dynamat or some equivalent. Note that doing two layers will give 2x or 3x the sound deadening so as long as you don't get so thick that you will interfere with the reinstallation of the carpet, seats, console etc you can do multiple layers and expect better results.
2. Pull up the carpet in the hatch area and cover the exposed hatch floor with the same product. In this case since the fit of the carpet is not as big a deal I anticipate that I'll do at least two layers and possibly go down to the carpet store and pick up a small piece of foam carpet pad that I will cut to fit under the carpet. This will increase the overall absorption in the back deck area. Buy more carpet pad than you think you need as you can use the carpet pad/foam creatively elsewhere during the process.
3. Pull the interior door panels off and cut a piece of the dyanamt or equivalent to cover the area between the interior piece of the door and the metal door itself. Pay special attention to cutting the material to fit correctly and make sure it bonds tightly around (not over..) the speakers and around any other openings. Make any incisions in the material (for wires, switches, door mechanisms,etc) as small as possible and if necessary seal the remaining holes again with tape or dampening material. Glue some of that extra carpet pad to the areas directly behind the speakers. If the door panel has large enough openings then stick some dynamat or equivalent to the back of the door exterior.
4. Pull the small panels where the rear speakers are and put sound deadener around those panels and around the speakers.
At this point the car should be much quieter and I'll give a good listen to see if some of the remaining noise is wind noise from around the doors, windows, sunroof, etc and if so then some of the rubber seals and weather stripping will be getting replaced.
I'll also be listening more specifically to see if I can identify any particualr noise source and then go to work specifically on that. At each phase I expect to hear less overall noise and at the same time expect to be able to zero in on specific issues as the noise level continues to drop. Some of this is going to be trial and error...
Note that like many things, if you really want to do it "right" it pays to be a bit **** about this stuff. Remember that you are trying to seal out noise so cutting the insulation to fit the spot precisely and cover all the little gaps and holes will pay big dividends. See an unused screw hole? Put some duct tape or dynamat over it...
If you are pulling out the seats and console you aren't going to want to do that too often so get it right the first time. Also keep in mind that in addition to sealing out noise you want to arrest it at its source if possible. So if you see an open body cavity you can take some foam/carpet pad or some polyester filling and stick it in the open cavity prior to sealing it. Some spray glue or brush on glue (even Elmers... can be used to help hold the foam or polyester in place) Be smart about this - don't use highly absorbant materials that will retain water and don't insulate and seal an area that might rightly need to be ventilated - fans, stereo equipment, electrical components etc.
Foam and polyester filling can be gotten at fabric stores where it is often used in pillows and cushions. Just cut foam to fit or stuff the body cavity with the poly filling. Note that I don't usually stuff the cavity entirely as I assume that it will get wet at some point and want some air to circulate so the area can dry.
If you are contemplating a stereo upgrade or speaker upgrade, this is the time to do it. The effect will be synergistic for two reasons.
1. The speakers generally like to fire into enclosed cavities (thats why your home stereo speakers are in boxes) and this is what you are creating by sealing out the rest of the noise and sealing the areas around the doors. Pay extra attention to giving your speakers a really tight fit and sealing the area immediatly surrounding the speakers. Also be sure to place some dynamat or equivalent directly behind the speakers and if possible also a little foam or polyester filling. Don't stuff the area, but do get something behind the speaker.
2. Lowering the overall noise level in the car is the same as increasing the output/power of the stereo. Ever listen to your home stereo late at night in the dark when all is quiet? Amazing how little volume you really need. In technical terms, lowering the noise by 3 db's is supposed to be the equivalent of doubling your ampliier power. A nice trade off.
So, I'm sure this is more than you ever wanted on the subject, but since I'm a new Porsche owner and new to the Rennlist community I wanted to make an effort to contribute. I have little expertise in mechanics and maintenance and I've already gotten a ton of good info from others here.
Moreover, since I'm faced with the same situation you are I thought I'd add my 32 cents worth in hopes that it can help.
Lastly if any other audiophiles have done upgrades to their 944/968's and have things to share I'd love to hear from you. Right now I'm interested in getting as many specifics on my current factory 10-speaker system as I anticipate replacing some of the speakers during the sound deadening project. Any insight from those audiophiles that have gone before me is appreciated...
Happy Motoring...
Phil
Phil0618@pacbell.net
I've got no experience with insulating under the hood, but I do have some with the interior. I'm a bit of an audio nut (both home and mobile) - some my comments below are theoretical but many are from practical experience doing some of my own car audio projects.
I just acquired a 968 (1994 Guards Red, Coupe) that has the chip, high performance exhaust and some big 265/30 tires in the rear and I find it too loud for my taste. I will be embarking on a serious sound deadening project in the next couple days...
First of all, sound deadening encompasses several things. There is the absorption that someone mentioned above which is basically having absorbent materials in the path/vicinity of the sound. This absorbant material intercepts the sound and 'holds' it and prevents it from echoing all around. Having multiple angles (rough finish as opposed to smooth is a start) will also help the sound deadening by dispersing the sound waves and giving additioanl surface area to absorb the sound.
In adition to absorption there is also the concept of blocking sound so that it simply can't enter the area you want to be quiet. Think of weather stripping, or think of shutting a window. Now you hear it now you don't... The seals around the windows and doors stop the sound from finding its way into the space. Once it has entered your only hope it so have lots of absorbent or turn up the stereo. On a car there are lots of little openings and channels for sound to come through and your job is to plug as many of them as possible.
You must think in terms of both sealing out noise and absorbing it. Your carpet is of course a natural absorber of sound while the glass is simply going to reflect everything back at you. The weather seals are attempting to stop sound from entering, but that missing or tattered insulation or that worn weather strip is letting sound leak in.
The fact that the car is a hatch back creates two problems - there is a large area that needs to be effectively sealed around the perimeter of the glass and of course glass is reflective - low in absorption. On top of all that, hatch backs and vans have another problem - the area directly above the rear wheels/suspension is in the interior of the car as opposed to being behind the back seat as they are in a sedan. This requires some extra attention.
So basically you want to do three things.
1. Seal out noise before it can enter the car
2. Absorb sound that does enter
3. Nail down (figuratively) anything that might vibrate or resonate and in turn add to the overall noise level.
Alternatively you can
1. Have an awesomely loud stereo, or
2. Travel with an extremely alluring member opposite sex so that you are continually distracted from the noise.
Products like Dynamat or RAAM mat or FatMat attempt to combine multiple attributes. First of all they are designed to stick to the surface they are applied to. This 'damps' the resonance/sound of that particular panel and also attemps to seal out any sound from leaking in. They are also typically multiple layers which also helps deaden sound. Multiple layers of different materials helps because different materials resonate at different frequencies and if you can get them in close contact the vibrations will cancel each other. Imagine knocking on a piece of metal. Now imagine gluing a thin piece of rubber to that piece of metal and knocking again. Less 'ringing' and less overall sound.
Your idea of trying to capture some of the sound under the hood is a good one, but before going down that road, give your car a really careful listen. When is the noise most offensive and where does the noise seem to be coming from? If its motor noise coming from the area in front of your feet then some combination of under hood instulation and some type of dampener on the firewall/floor might do it. If the sound is coming more from wind noise that is different and if it is exhaust note then that is something else again.
Also note that low notes/sounds can be tougher to erraticate than high frequencies. The ear is very sensitive directionally to high frequencies and you can pinpoint those easily and hopefully stamp them out at the source. Low frequencies tend to be "omni directional" (they seem to come from anywhere and everywhere) and they also tend to excite resonances in other materials. This omni directional thing is why you can use one subwoofer instead of two. The ear can't really distinguish the stereo effect at really low frequencies.
So, having said all that here is what I'm planning to do on my car and in roughly this order.
1. Take out the front seats, center console and carpet and cover the entire floor of the car with dynamat or some equivalent. Note that doing two layers will give 2x or 3x the sound deadening so as long as you don't get so thick that you will interfere with the reinstallation of the carpet, seats, console etc you can do multiple layers and expect better results.
2. Pull up the carpet in the hatch area and cover the exposed hatch floor with the same product. In this case since the fit of the carpet is not as big a deal I anticipate that I'll do at least two layers and possibly go down to the carpet store and pick up a small piece of foam carpet pad that I will cut to fit under the carpet. This will increase the overall absorption in the back deck area. Buy more carpet pad than you think you need as you can use the carpet pad/foam creatively elsewhere during the process.
3. Pull the interior door panels off and cut a piece of the dyanamt or equivalent to cover the area between the interior piece of the door and the metal door itself. Pay special attention to cutting the material to fit correctly and make sure it bonds tightly around (not over..) the speakers and around any other openings. Make any incisions in the material (for wires, switches, door mechanisms,etc) as small as possible and if necessary seal the remaining holes again with tape or dampening material. Glue some of that extra carpet pad to the areas directly behind the speakers. If the door panel has large enough openings then stick some dynamat or equivalent to the back of the door exterior.
4. Pull the small panels where the rear speakers are and put sound deadener around those panels and around the speakers.
At this point the car should be much quieter and I'll give a good listen to see if some of the remaining noise is wind noise from around the doors, windows, sunroof, etc and if so then some of the rubber seals and weather stripping will be getting replaced.
I'll also be listening more specifically to see if I can identify any particualr noise source and then go to work specifically on that. At each phase I expect to hear less overall noise and at the same time expect to be able to zero in on specific issues as the noise level continues to drop. Some of this is going to be trial and error...
Note that like many things, if you really want to do it "right" it pays to be a bit **** about this stuff. Remember that you are trying to seal out noise so cutting the insulation to fit the spot precisely and cover all the little gaps and holes will pay big dividends. See an unused screw hole? Put some duct tape or dynamat over it...
If you are pulling out the seats and console you aren't going to want to do that too often so get it right the first time. Also keep in mind that in addition to sealing out noise you want to arrest it at its source if possible. So if you see an open body cavity you can take some foam/carpet pad or some polyester filling and stick it in the open cavity prior to sealing it. Some spray glue or brush on glue (even Elmers... can be used to help hold the foam or polyester in place) Be smart about this - don't use highly absorbant materials that will retain water and don't insulate and seal an area that might rightly need to be ventilated - fans, stereo equipment, electrical components etc.
Foam and polyester filling can be gotten at fabric stores where it is often used in pillows and cushions. Just cut foam to fit or stuff the body cavity with the poly filling. Note that I don't usually stuff the cavity entirely as I assume that it will get wet at some point and want some air to circulate so the area can dry.
If you are contemplating a stereo upgrade or speaker upgrade, this is the time to do it. The effect will be synergistic for two reasons.
1. The speakers generally like to fire into enclosed cavities (thats why your home stereo speakers are in boxes) and this is what you are creating by sealing out the rest of the noise and sealing the areas around the doors. Pay extra attention to giving your speakers a really tight fit and sealing the area immediatly surrounding the speakers. Also be sure to place some dynamat or equivalent directly behind the speakers and if possible also a little foam or polyester filling. Don't stuff the area, but do get something behind the speaker.
2. Lowering the overall noise level in the car is the same as increasing the output/power of the stereo. Ever listen to your home stereo late at night in the dark when all is quiet? Amazing how little volume you really need. In technical terms, lowering the noise by 3 db's is supposed to be the equivalent of doubling your ampliier power. A nice trade off.
So, I'm sure this is more than you ever wanted on the subject, but since I'm a new Porsche owner and new to the Rennlist community I wanted to make an effort to contribute. I have little expertise in mechanics and maintenance and I've already gotten a ton of good info from others here.
Moreover, since I'm faced with the same situation you are I thought I'd add my 32 cents worth in hopes that it can help.
Lastly if any other audiophiles have done upgrades to their 944/968's and have things to share I'd love to hear from you. Right now I'm interested in getting as many specifics on my current factory 10-speaker system as I anticipate replacing some of the speakers during the sound deadening project. Any insight from those audiophiles that have gone before me is appreciated...
Happy Motoring...
Phil
Phil0618@pacbell.net
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09-02-2004, 02:25 AM
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I have recently completely re-done my whole interior (an 83 944). I basically stripped the whole inside of the car and sprayed the whole bottom with a sound deadner, used a Dynamat type sound deadner, new carpet, and new door and hatch seals . Probably the most valuable improvement I made to lessen road noise is the door seals and the hatch seal. When I was driving above 60 there would be an excessive amount of noise coming from wind (not to mention leaks), and after replacing these they were almost elimanted. You have to play with the pins that are on the hatch to get it to seal right, but I think this is the most effective thing you can do.
I am going to post pictures of the interior upgrade soon. It is my first big project and I am very excited about it. The car sounds great!
Good luck
I am going to post pictures of the interior upgrade soon. It is my first big project and I am very excited about it. The car sounds great!
Good luck
09-02-2004, 02:29 AM
#9
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Originally Posted by josephsc
Wow -- only TWO YEARS to get a response. Must be some kind of a Rennlist record.
No kidding. I bet it was one of this 1st posts too. Now hes over 2000.
09-02-2004, 10:19 AM
#11
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Originally Posted by Serge944
No kidding. I bet it was one of this 1st posts too. Now hes over 2000.
.
09-04-2004, 02:03 PM
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Tifo- I think Joseph sc was referring to Dave's reply- MY last reply in this thread was 8/22/02- I became a RL member in OCTOBER of 2003- hell, that means I've been a member for ALMOST a full year- time to renew :-) Anyway, Dave must have done an archive search to find info on this subject- cool, there ARE people who still know how to do this :-) his reply was 9/1/04. Anyway, as for the "old" vs "new" Robby- I'm still the same Robby- I know, I contradict myself w/my interests sometimes- I want FAST & LIGHT, but, QUIET- I ALSO want RELIABLE- Chris Cervelli once said something that has ALWAYS stuck w/me: there are three things to want- FAST, RELIABLE, & CHEAP- pick any two... in other words, you will NEVER have ALL three.... hell, try throwing QUIET into the mix & you'll REALLY be unhappy... I just like the quiet of cars like BMW 540i's- they have this EFFORTLESS speed feel to them- they are fast (about like a stock Turbo S) & QUIETER at 120mph than our cars are at IDLE.... Anyway, Tony & Phil have covered this subject well- their points are dead-on- I've found that noise enters these cars in several ways- bad seals (particularly hatch, but, windows wear out too)- transmission noises- lost of noise enters through the rear deck- the fact it is a hatchback (coupes, sedans, are ALWAYS quieter) sound seems to always come from the rear in cars- I THINK that's ONE reason why BMW 540is od so well- they are sedans, so, don't have rattles from hatches- they also seal that rear area off- the tranny, etc- they have MULIT-LINK suspensions in the rear- makes a BIG dif- ALSO in road handling & FEEL over rough surfaces. Anyway, our cars also let noise in through SR rattles- the engine does add a little, but, I added sound deadening there & didn't notice much- THAT is when I started trying to isolate my problems- the tranny is bad- new foam in the shifter WOULD help- also, the exhaust- I have an SFR 3"- loud as hell- I'm TRYING to find a way to add a new Borla XR1 in the diagonal section- it looks to be too big though- pissed b/c I ALREADY bought it- I want at LEAST one more muffler & PREFERABLY a different one from the Bullet (SFR)- Tim has a newer one that he says is MUCH quieter- persoanlly, I'd almost like to have a muffler/resonator from the turbo back, but.... in any event, the SFR exhaust IS lighter, but, it's not a good thing so much b./c it's at the wrong end of the car, not to mention it's below the Cg- the absolute worst place to remove weight, athough I'll take what I can get- anyway, there are now a few EXCELLENT responses here on this thread- plenty of ways to go.... I kinda like Phil's 2nd "alternative" point on making it better: "Travel with an extremely alluring member opposite sex so that you are continually distracted from the noise." :-)