One thing I forgot to mention that might be of interest is that now I can actually hear the sound system, too - whereas before it was really contaminated by the road and tire noise. There was a major difference there, IMO.

Here is a good link to information on what to cover and how much to use from a guy that did a lot of product testing.

Sound Deadener Showdown - Your Source for Sound Deadening Products and Information

EDIT: this is not the original data he had posted years ago comapring all products on the market, seems to be selling his own stuff now. I think there is still some good info here though.

I can actually hear the engine better which to me would mean a better sports car experience..

I think your report is accurate Charlie. I dynamatted my doors and small areas of the hatch last week. Not a considerable difference, but it is noticeably quieter. I can hear my motor and speakers more. I may add more Dynamat along the rear speaker area if I decide to add rear speakers.

I have thought about this: there is a stretch of freeway that I travel that has various surfaces and really plays a symphony, or rather cacophony with the tires. The thing to do would be to use a recording measuring device and travel a certain section of road, long enough to get a good reading. Maybe 10 miles. Stay in one lane, at one speed as much as possible, A/C and stereo off & windows up. Take a measurement maybe every 10 seconds with the microphone in a fixed location, like attached to the inside driver side headrest strut. Install the Dynamat & repeat the test. Print out the graphs or plots and look at the difference in SPL at the same locations and elapsed time. There you go.

OK, so since I had a 350Z, I am well aware of the rear tire noise..So no shock here when the 370Z did the same thing..

The RE050's have 50% tread on them left, so my first thing I will do when they get more worn out, is to Buy some Pilot Super sports..

I want to see what that does before we do any sound deadening..

Well what is stopping you from doing just this? :)

Dynamat 10455 Xtreme Bulk Pack 9 Sheets by Dynamat is on sale for $139
at Amazon.com and that cover hatch and 2 door and about 4 to 5 hours of work and is not that hard to do and is about 30% to 40% improvement on road noise.

Cash. None to buy the audio meter and software and none to pay some shop to do the Dynamat, especially since I don't want to remove the door panels myself or spend a day as a contortionist working in the hatch area:tup:

Will that one pack really cover both the hatch and doors? I have seen some dynamat door panel packs. Is there a difference?

There's an app for that!! :)

Did exactly what you mentioned. After installing the sound deadening liner in the rear hatch the level of noise in the cabin dropped 10db (using the iphone, same stretch of road, same speed, dry road.

yeah the door only need 1 for each door and you have 7 left and i think the door panel is the same and i google it i see they put in Dynamat Xtreme but in little pieces i think hey but they work for me.

Here is an interesting site that lets everyone hear what various db levels sound like..I wonder how much more you get with quieter tires?

dB: What is a decibel?

PS I just listened to the sound graphs..the math was not something I cared to deal with..:)

I got a Dynamat bulk pack from Amazon. I was able to cover everything in the trunk area and rear wheelwells 100% last night. Nothing left over for the doors so I bought another bulk pack.

I had the cabin floor area done, too, yesterday while they were putting in the remote start kit. In driving around, it seems to have made a small difference, although I could be fooling myself since things are down to the finer shades of gray now. After replacing the tires, doing the sound treatment on the back, doors, and floor, I would rate the soundproofing something like this as to bang for the buck:

1 - Tires
2 - Back (Hatch) Area
3 - Doors
4 - Cabin Floor

I also had them raise the back mounts of the passenger seat by 1 inch. They got longer bolts (factory bolts were too short) and fabricated a slightly-sloping spacer to do that. About an inch is the amount of adjustment of the rear knob on the driver's seat, and the seat is more comfortable now. My wife swears it went up by at least a couple of inches - and she is thrilled to now see over the dash! I rather passed off how much it was raised with somethiing like "As long as you're happy...." But that 1 inch did make some significant differences even if some of it is "apparent" to the person involved.

I'm quite happy now. The car is reasonably quiet, we can carry on conversations, and my wife (and I as well when I sit in that seat) is happy in the comfort and improved view of the passenger seat. The remote starting (something I've had on many cars) is great as always. Love the car, and it's really fun to drive - which was the whole idea.

Hold the phone......:excited:

I have thought about this for a while now, and I'm very interested in exactly what they did. Perhaps you could start a new thread (to not derail this one), and post up some pictures. With the limited seat adjustment, I have to assume others would be interested too.

Please, more info......:tup:

My wife has the same complaint...let us know when you post something about how this was done..

Raising Rear of Passenger Seat
 

I'm too new to this forum to know how to redirect readers to a different thread on this topic, but I'll post a response here and if someone moves it over so that I can follow I'll try to keep up - - -

= = = = =

Here's what happened. I noted the adjustment for the driver's side, and did a rough eyeball estimate that it moved the back of the seat bottom up and down about an inch or so, total. I also noted that the passenger seat was pretty sloped and since it had no adjustment I discussed it with the installers.

Things we discussed were that if the back were raised, the factory mounting bolts might not be long enough (which proved to be the case), and that they were probably hardened bolts. The installer also thought that the upwards tilting of the back might put some stress on the front bolts so he theorized adding a very small slanted spacer in the front.

Initially I had studied the room between the cabin roof and the passenger seatback/headrest, since the bottom of the seat wasn't being raised relative to the seatback but rather the whole seat would be raised in the rear - seatback and all. It appeared that there were easily a few inches of headroom with no adverse affects for a 1 inch rise. Someone who is really tall might reconsider that but for most people I figured it wouldn't be a problem. My wife had said when she sat in the driver's seat (which I leave permanently raised all the way in the back) if felt more comfortable. So I figured one inch would be a good matching target amount for the passenger seat. You could probably go some more if you wanted.

In the end it turned out to be really simple as they only had to do two things:

1 - Add two aluminum spacers of 1 inch with a very slight cant on them (to account for the sloping angle) at the back of the seat rails.
2 - Replace the factory bolts at the rear with 2 longer hardened bolts, which they easily obtained from a local nut/bolt specialty shop. They also selected a suitable washer for each of the new bolts. (I told them not to worry about the little plastic cap that covered the original bolts as they were out of sight anyway.)

The installer told me that when he looked at the front of the track mounts, there was a slight slant already there and thus he saw no reason to have to do anything with the front mounts.

The whole thing amounted to about a half-hour of labor, throwing some black paint on two slightly canted 1-inch aluminum spacing pieces (from square aluminum pipe or tubing - I just glanced at them and didn't ask what he used - you could probably use regular pipe for that matter), and bolting the seat rails back in with the two longer bolts in the rear.

We just downsized to a condo and I don't have a workshop any more so I just had them do it for me, but it'd really be an easy DIY job.

My wife loves it. Suddenly the whole ride was improved in her mind - especially the view since she is short. The seat is more comfortable at this angle for me, too.

If you just start an entire new thread (you know how to do that?), then I can link this conversation over there. Just copy the post you made here, start a new thread, then paste it in.

To start a thread, just go to the main forum listings, go down under Interior/Exterior Mods, click on that, then go all the way to the bottom and click New Thread.

I have to say, I think your guy who made the spacers might be able to make some coin by selling kits with 2 spacers and 2 bolts. I know I would buy one if the price was right. I have not only been considering this for the passenger, but also the driver seat. I had all your same reservations, but came to the conclusion that for me the spacer was the only hard part. It's hard to see in your picture exactly what it looks like. To me, that's the key. The bolts I can get easy.

Thanks for this info. Let me know if you need any more help, and if you see your installer guy, could you ask him if he could make 2 more sets for me? :o:tup:

i posted this long time ago somewhere. it's a modshack mod...

Must have been a LOOOOOOOONNNNNGGGGGG time ago kenchen, because crap, I'm old, and I've never seen it. You must be archaic?? 16,000+ posts means OLD or SUPER GEEK, for sure. :nutswinger::icon17:

Can you find it for us, you old super geek one you? ;)

I just edited the post and added the text below to item #2 near the end - I had forgotten this one minor detail:

"They also selected a suitable washer for each of the new bolts. (I told
them not to worry about the little plastic cap that covered the original
bolts as they were out of sight anyway.)"

You can see the washer underneath the bolt head in the picture.

- - - - - - - - - - - - -

The "spacer" is just a piece of squared aluminum stock, slightly tapered on one cut end to take in the angle off the cabin floor. A piece of pipe would also work, utilizing the same kind of taper, etc.

I created a new thread under the DIY Section entitled "Raising Rear of Passenger Seat Cushion".

i made a DIY just for you and pintsize. lol :tup:
here you go..

http://www.the370z.com/diy-section-d...isibility.html


i got tired of sending PM's... and trying to remember what i did. :icon17:

i asked the moderator to merge your tread into mine so that people can see both of ours together.

credit goes to modshack.

My wife just said to save the money and let her sit on a pillow.. fine with me..

Thanks, kenchan.

RI: I don't want any pillows around in the car. When I make a close pass, my wife might smother me with it.

that's fine too especially if you're not a car person and do not need the vehicle dyamic feedback.

:tup: np, i should've posted the DIY earlier since i remember typing up the same thing a couple of times over the years. :icon17:

and yah, no pillows in my Z. im not phelan.

As well she should!! :)

pass as in driving, not farting...

Yeah, right!!!!

Back at cha......:icon23:

(And actually, we have heated seats and I don't want pillows because in the winter that would defeat part of the heating operation.)

I'm embarrassed to admit this, but here goes...

I thought my Z was super-loud on the road noise from day 1 (I'm at about 1800 miles). Getting ready to go on a 1400 mile trip next week, so I thought I'd check my tires. Holy crap! I was between 45 and 48 psi. I'm sure a few of those psi are from going from 20 degrees when I picked the car up to 70 degrees now, but I have a feeling they were overfilled from day 1.

And I'm usually really good about checking my tires, but my gauge was in my truck and it's kept one place, the Z another. But I should have checked.

End result is this: road noise was cut by over half when I went to 35 psi. Like you can actually carry on a conversation now! My wife is very happy. And the ride is much improved though I definitely see the need for sway bars with the properly inflated tires.

So check your tire pressures (along with everything else) - it makes a huge difference.

Tires
 

I found that my change to Hankooks, although much larger, offer a quieter and softer ride. Psi level also contribites as Scott mentioned. Strangely, I hear very few pings in the wells from debris. Is it the tire tread configuration?

Why do you need vehicle dynamic feedback if your in the passengers seat?

I have the problem solved: I've got a 60 decibel hearing loss. The noise doesn't bother me at all, but it bugs my wife.

So I was wrong about my earlier price quote for the Dynamating. It's actually less! They (a very reputable shop recommended by a lot of socal forum embers quoted me $140 for labor for both he hatch and the doors. That means I can buy the bulk pack and the door kit form Amazon for $190 + $140 install = $330 total cost for hatch and doors. Seems like a great deal.

It cost me $1200 which means I could have driven to California, got the job done and driven back and still saved money!

Hey! I told you to come by my house.

Yes
 

Yes you did and I guess I should have taken you up on it.:(..I could have spent the winter there with my wife and four dogs, two cats and a goat.. arriving in early October and leaving in late May.....enjoying your cooking and spirits..Is that invitation still open?
PS and off topic, but what is this Rep Power thing? and those green buttons below it?