86'928S MeteorGrey

When I was dropping my transmission, there was what looked like house wall style fiberglass insulation wrapped around the torque tube. I understand the desire to keep the TT bearings cool, but... The paper outer layer is mostly burnt away. Is this stuff supposed to be in there, or is it something a PO did? I can't find/see the insulation in the PET...

Any info appreciated. I'm waiting to put the new transmission in until I get an answer on this.

blown 87

There are two pieces of foam on the S4 auto and from what I see, one on the S4 5 speed.

house insulation does not belong there.

86'928S MeteorGrey

I didn't think so.

Foam? won't it melt from the exhaust heat?

Is the foam intended to insulate noise or heat? (or both?)

Crap... Now I can't finish my transmission install this weekend.

Anybody run without the foam pieces?

Black Sea RD

Hi Mike,

Greg is correct! No house insulation should be on the TT.

The foam OE pieces should be placed back on the TT since it will help keep dirt, heat and noise from invading into your cabin, even through the gear lever rubber boot. That's why Porsche made them in the first place.

I'm sure 928 Intl., 928 WW or others here on the list can probably set you up with one.

HTH,

blown 87

Yep, until they pull everything out to put the right stuff in there.

Get the right parts.

Rob Roy

Mike,

There was no foam around/on the TT when I pulled it so it may have been a replacement - it did look in great shape when I pulled it. Hope things are going well!.

docmirror

For auto trans cars there should be a molded expanded foam seal that goes around the top of the TT and over the shifter. It insulates the top of the tunnel so that the interior doesn't get hot air up in it.

I just went though this on my 86. If you are missing that foam, roger can get you a new or a used one. If you don't use it, the car will get A LOT of hot air up through the shifter. The cats are directly below the shifter slot.

Get the foam and use it. I also supplemented my foam with the home insulation expanded stuff that you can buy in a can. I sprayed some of it up above the heat shield around the TT and my hot air problem is not as bad now. I'm going to add some more around the heat shield to make it even better.

SeanR

Ask Doc about that foam piece.

I won't kiss and tell, but was a funny couple of days.

SeanR

DOH.....he is reading the same thing I am.

86'928S MeteorGrey

One thing I never had was heat coming out of the center column. I did tie wrap the heater valve closed as soon as I took possession of the car, but otherwise it seems like the column was getting zero positive, or negative pressure. I took some photos of the insulation but had to find the card they were residing. I like the idea of extra insulation though. I wonder if the full wrap of glass stuff was doing better sound reduction of the TT bearings. If it were not for the fact that I have had to deal with fiberglass on the forearms afterwards, I'd be inclined to put some in again only with the paper side toward the TT....(DER.) I have not heard any TT noise at all... Only the damn TC bearings...

Anybody got any photos of the original pieces for the S4 auto?

I suppose I could drop the exhaust on the S3 to see what they look like. Or are the insulators different from 86.5 to S4?

I'll get the originals, foam the areas as per Doc, and maybe look for alternative lightweight methods to wrap the TT

Featureed are the infamous OB brakes on an S4...

docmirror

The reason you weren't getting any heat out of the shifter console was all that insulation stuffed up there. It effectively blocked the airflow up to the tunnel. I'm betting one of the main reasons all the foam is up there was heat coming out of the shifter. When you remove it, you may have some heat coming up. I'm going to increase the spray foam I've got up there, but not as much as this car had.

86'928S MeteorGrey

The way it was kept all the heat flow out of the shifter. I'll remove the glass stuff, but part of me is thinking it could be doing a great job of protecting the TT bearings from more heat than an OEM setup provides. There is no data to back it up, but it makes logical sense to me.

Mike Frye

Mike,

I'm not sure that theory works. I'd think airflow around the TT would be good at diffusing the heat of the exhaust and TT better than wrapping it. My guess would be that the insulation is for sound deadening rather than to keep heat away to protect the TT bearings. If anything I'd be concerned that it would keep the heat of the spinning bearings in and reduce their life.

86'928S MeteorGrey

Hmmm. I hadn't thought of that. I won't reinstall it. I was going to replace the TT, but now in interest of science, I'll go with the original TT to can see if there is a difference in noise and heat.

blown 87

You really need to have at least the factory insulation in there, gonna get hot with out it.

Putting new foam and MM on mine made a big difference.