Sound proofing

[zacob]

http://www.mitsubishi-fto.org/pdf/soundproofing.pdf

Did anyone try soundproofing the cars floor-pan as described in attached link. Is there much work in striping the inside like shown. Does it have improve on noise levels much.

[CJ]

Did anyone try soundproofing the cars floor-pan as described in attached link. Is there much work in striping the inside like shown. Does it have improve on noise levels much.

By soundproofing the floor plan, I believe that a substantial improvement can be obtained in terms of reducing road noise and vibration but you'd really need to be useing Dynamat or similar, all that flashband is gonna weigh the car down!

CJ

[Mustang]

Zacob,
I havn't tried this myself, but let us know how you get on.
I am doing some soundproofing on my car, a little at a time.
The story so far.
Bitumen self adhesive sheets (similar to flash band) on the inside of the boot lid, as described in the above link. I don't think these patchs are enough to have much of an effect. Planning to put more on and make a cover for the inside of the lid, as suggested by CJ in an earlier post.

I also stripped out the rear seats, parcel shelf and rear 1/4 panels, fire wall between boot and passanger compartment and entire contents of the boot.
I lined the inside of the 1/4 panels with the bitumen sheets, I also covered the parcel (speaker shelf) and all the vertical panels that I could.

When you take off the rear seat it gives you access to the floorwell.
I didn't use the bitumen here.
Very uneven surface lots of contours, therefore not practical to apply in large sheets as you will never get it to sit right, and match the exact contours of the floor.
Following on from this I was concerned that it would interfere with the way the seats rest on the floor.

So instead I used tetroseal, rubber spray. Sprayed the whole rear floor well and all of the boot.
Tetroseal is intended for use as a rubber underseal for cars (thats why I bought it in the first place....another project on the to-do list), but also recommended for sound deadening.
This stuff is just like a paint so it's very light.

If you were going to use a rubber spray such as this. You could apply it to the underside of the car. This serves the joint function of sound dampening and sealing.

After all this, I'm not convinced of the results, the project continues.....

For what it's worth, I think that most of the fto noises come from the following places.
Front: Wheel arch liners become loose (damn cheap plastic screws )
Also the interface 'box' where the wheel arch liner joins with the bumper.
There is a hollow plastic compartment. I'm pretty sure this is what generates the front end noises, as it rattles about.

Back: There is a heat sink/ heat shield over the exhaust back box/ muffler. This can generate a very 'tinny' noise and while mine wasn't loose it did rattle, used some bitumen to damp it down.
Also I think that the main cause of the rear end noise is the fuel tank.
Not positive on this. I'm planing to cover mine with bitumen sheeting.. will keep you posted.

Mustang

[mcgon1979]

sorry to raise the dead here... Im looking to source some form of sheeting to line the floor of the car. The GPvR has no sound proofing/deadening at all. If I look under the passenger floor well I can see the engine wall etc. Think the noise (from wheels) is coming in here and through the floor mostly. ebay only had very expensive stuff and expensive shipping too. ANyone done this job any advice. Is it hard to get the carpet up to line the floor plan? defo something I want to do. Not expecting merc style results, but just want to reduce the wheel roar if I can. no exhaust noise problem, its all wheel/tyre roar/road noise.

[Muad_dib77]

Halfords had some Dynamat last I was there - wasn' t cheap though.

[CJ]

Mgon, what tyres have you fitted? I find that tyre choice can have a huge impact on road noise, in my experience, Toyos and Eagle F1s are loud, Vredesteins are very quiet in comparison.

If you want to soundproof the floor plan, give yourself a full day. Once the seats are removed (20 mins), its a matter of removing all of the additional trim in an effort to get the carpet up. Clean the bare floor before applying soundproofing. Dynamat or similar is light but pricy, flashband is cheap but heavy (and flammable!)

CJ

[mcgon1979]

Thanks CJ, good info there. Yeah the stuff seems very pricey lads. 40euro for a 12x12inch square... The tyres Im running at the minute are Kuhmo. Might order the vredesteins next time.
I wonder would it help much at all to stick some materials up under the passenger footwell. I can see the bare engine wall / bulk head there.
It sounds like a big enough job to remove the seats/trim and get the carpet up cleanly. I might not bother going to those lengths. It's not too bad, but its quite annoying on coarse road (old motorway surface).

[CJ]

The tyres Im running at the minute are Kuhmo.

I had Kuhmo Ecstas some time back, they're a hard compound tyre if I remember corectly and noisy to boot.

Personally, I'd use flashband to soundproof the floor, on the downside, you'll end up adding another 15kg or so the kerb weight.

While I'm sure you haven't lost sight of the fact, road noise in a GPvR is going to be more prominent that other models - you've got the lightweight sports model after all! You could always swap it for a quieter / feature rich GPX

CJ

[mcgon1979]

You could always swap it for a quieter / feature rich GPX

hmmm.... maybe not... I might just try and stick some sound proofing in around the bulkhead. You can see it clearly from the passenger footwell along with the bar/cage frame of the car etc. They certainly didn't skimp on the lack of soundproofing. NONE! hehe. I'll take your advise on the tyres though mate, sounds like the Vredesteins will be hit next instead of the Kuhmo.

[escu_calin]

hello

i'm following this thread because it is most relevant

i found my self on this road of killing the insupportable noise inside my car and i do it by two means:

1) replace all my bushings , drop links, shock absorbers and springs ..
2) and .. related to thread by soundproofing the most noisy parts of the car.

the questions i raise is if anyone has ever used products like this:
http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... TQ:GB:1123

and being bitumen based i know they're flamable.
but what i don't know is if it affects the car smell a lot and if in 40-45 degrees Celsius environments they keep cohesion and don't melt away.. since in Cyprus during summertime 40 degrees is a cool breeze (especially from door sides and skin ; where sound damping is a must )

thanks

[CJ]

Heat will definetely have an impact on the external panels such as the doors, in 40 deg heat, you might find that the bitumen will soften and peel away from the inside of the door. ON that basis, I'd recommend Dynamat or Brown Bread (not the eatin' type!).

CJ

[Kace]

Heat will definetely have an impact on the external panels such as the doors, in 40 deg heat, you might find that the bitumen will soften and peel away from the inside of the door. ON that basis, I'd recommend Dynamat or Brown Bread (not the eatin' type!).

CJ

Hmm - never thought of that. I've had flashband installed in boot, doors, floor for years now (makes a big difference in the solidness of the doors). We don't generally have the 40 degree heat to contend with though.