I choose do try and make one of my 240's as comfortable and quiet as possible. While I had the carpet out for washing and some minor rust cleanup I deceided to install 36ft2 of Dynamat extreme. I did the doors, inside of rocker panels and added to existing soundproofing on the floors and tunnel area. Still need to do the trunk lid and hood. Overall I'm pleased with the results. The most noticable noise right now is the front tire noise which are 15"'s. I will eventually go with some of the quiet ride tires. Would 15" tires be noiser than 14"'s? I did the front suspension with poly bushings and like the results alot although that may be why the tire noise is more noticable. How will the ride suffer if I do the rear TAB's and torque rod bushings in poly as these bushings need replacing although I can't say I can tell much? How is the IPD quiet hood kit?

I bet you'll get 2x the decibel reduction from adding 740 style door seals outboard of the regular door seals. Wind noise is what usually dominates in my 240s. I know later ones had better door seals anyway.

Then again I usually drive with the windows down as much as possible, so I don't care that much about noise.
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Rob Bareiss, New London CT ::: 87 244DL, 88 245DL, 90 745GL, 84 242DL project, 89 244 parts, 88 244DL to replace the 87

I have the IPD hood kit on my 83- it made a HELL of a big difference. It is truly worth it. However, on my 71, I just went to Home Depot and bought a big sheet of foil backed insulation. I used Mylar tape and installed in under the hood.
If you want to really go far, pull the hood pad from a 900 series and adapt. I have heard that this can be done, but I have not done it myself.

Jeremy
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71 142E and a yard full of 240's in Mass.

Your results with the bushings will vary, i.e. depending on the condition of the current rubber. I believe good rubber will always be quieter than poly.

One thing that can happen with poly TABS and torque rod bushes is this: Remember that your engine is vibrating, but those drivetrain vibrations are completely isolated in rubber (engine mounts, trans mounts, and suspensions mounts). The engine vibrations are transmitted to the trans, driveshaft, and rear axle. When you replace the rubber suspension bushings (rear only) with poly, you're firming up the substance that isolates the drivetrain vibrations from the body and interior. Your TABs will allow increased vibration right under the back seat. At times the floorboards can become a giant bass drum. Some people never encounter this problem, but some do. It is particularly noticeable if your have a manual tranny and use the engine as a brake.

Just FYI. If quiet is your goal, stick with new rubber in the rear suspension.

Yama,

I think the brand/type/model of tire you choose as opposed to the size will have the greatest impact on noise. Check the noise and other ratings from consumers at the tirerack.com The Tire Rack is also a good place to get good prices and quality tires. My Yoko touring tires produce very little road noise, check others out on the Tire Rack survey page.

http://www.tirerack.com/index.jsp?source=S13674x010-branded&code=yes&keyword=www%2Ctirerack.com&

Why did you cover up the linkages and holes? Hmmmmm.

When I FatMat-ed my ride, I left the openings in the door uncovered (not the way you did it) so that I could do the back of the outer door skin like the factory did but better.

I am sure you saw the original piece of perforated tack mat on the inside of the door? Just cut pieces that fit through the holes. Long strips work best.

Plus, I did the door frame (like you did without covering the holes, but wrapping the edges) so that I could potentially work on the inside of the door if necessary.

And, I put some on the back of the cardboard door panel too. I also primed, painted, and polyurethaned the back of the panel for protection from mold and moisture -before applying the sound deadening mat.

I found a heavy gauge plastic sheeting that I used as a barrier as well.

Did the trunk, lid, and rear quaters. Worth it.

Have the hood quiet kit, worth the money too. Looks nice and honestly works great.

I say bush the car in poly, the ride is better in my opinion.
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VX, adj. cam gear, new head, trans cooler, stainless brake lines, electric fan, fully braced, IpD sways, poly bushes, Bils, boxed front & rear arms, lowering springs, 16' Perfos, 25/32mm adapters, 100% zero mile-d, and much more

"Why did you cover up the linkages and holes?"

This is the way Dynamat recomends doing it for max effectiveness. They say the mat can be removed if and when any service is needed. Pior to doing this I put loctite on all the window regulator nuts and door handle screws and liberally lubricated the window mechanisms. I didn't press the mat up against the linkages so they can still move freely. Each door came out slightly different. I also put 2 coats of mildew resistant exterior latex on the door panel fiber board along with re-installing the orginal plastic liner.

That hood liner kit sounds like a future project.