Sunroof Headliner Cosmetic Only?

[66Vette]

Does the sunroof headliner have any other function than appearance?  I assume it offers some level of sound proofing from outside wind noise, but does it really need to slide in the grooves of the sunroof side rails?  Or do the grooves aid in sealing the headliner against noise?  Or maybe added thermal barrier?

[dlacey]

Its just headliner fabric stretched over a frame, so not a great thermal or sound barrier... i think the only reason it slides in the rails is mechanical/cosmetic to make sure it fully blocks the hole and looks nice.

[Mike Self]

The sunroof headliner material is glued to a flexible steel frame that clips to the forward edge of the sunroof panel itself and should slide back and forth wit the panel.  If the original rather thin material is replaced with a thicker headliner material--like the perforated material used on VW Beetles and MBs of the era, it won't slide properly and will tend to hang up.

 

But to answer your question, it does provide some soundproofing, but otherwise cosmetic.  The underside of the sunroof panel is just bare metal, same as if you removed the headliner from the rest of the roof.

 

mike

[TobyB]

Yes, the original BMW vinyl did do something to dampen sound. 

Being non- perf, it acts as a trapped air space.

 

Likewise, that would insulate to some extent.

 

And look pretty.

 

How effective? 

Probably only 3.4 dBspl @330 Hz, R 2.3,

and not quite as pretty as a flower vase with 2 dandelions...

 

t

 

[66Vette]

Thanks guys, that helps me move forward.

 

 If anyone is up for brainstorming, what if you put cosmetics down the list of importance and were after a simple sunroof headliner that made sunroof maintenance, ease of assembly/disassembly, and simple fabrication at higher importance?

 

Searching the archives of 2002faq, I see bent sunroof headliner frames, headliner fabric bunching in the grooves of the side rails and inhibiting movement, and added hassle of having to pull a side rail to remove/install the headliner.  There are a lot of posts on sunroof problems!  

 

The original design engineers probably had cosmetics (marketing) and cost at the top of their list.  My motivation is ease of assembly, smooooth operation, and longevity.

[oldbugr]

12 hours ago, Mike Self said:

The sunroof headliner material is glued to a flexible steel frame that clips to the forward edge of the sunroof panel itself and should slide back and forth wit the panel.  If the original rather thin material is replaced with a thicker headliner material--like the perforated material used on VW Beetles and MBs of the era, it won't slide properly and will tend to hang up.

 

But to answer your question, it does provide some soundproofing, but otherwise cosmetic.  The underside of the sunroof panel is just bare metal, same as if you removed the headliner from the rest of the roof.

 

mike

I am always amazed at the things I learn from people like yourself. Now I know what to look for to ensure no drag on the lid.

[66Vette]

Sunroof backside and sunroof headliner

 

 

[TobyB]

The sunroof is also not a BMW design- they bought it from a 3rd party that also sold parts to Portche and Volvo,

and probably others.  So they were using someone else's 'intellectual property' and parts, and stuffing it into their cars.

 

Which makes sense- if the design worked, why spend real time trying to redesign the... sunroof?

In 1974, there were at least 2 manual sunroofs made by Webasto that were installed in 2002s.

I had one, and someone else here has one, too.  It's got a t- handle, and works like a Saab 99's does.

 

I do recall a thin layer of open- cell foam glued to the metal lid, too- it usually falls off, and pooches down

the headliner fabric.

 

As to what to do with the thing?  That's uppa you.  I see no shame in redesigning it, welding the thing shut,

or replacing it with something better.  Pop- rivetting an aluminum sheet over the whole mess... well, if it matches

your aesthetic, go for it.

Just be ready for flames when you put it up on BaisteaTurkey as a 'pristine one- owner wrapped nugget of horsepower snuggles'

(can I just tell you how annoying I find BringaTrailer?)

 

t

 

 

[66Vette]

Toby:

 

Thanks.  You are right about the foam.  I tore off mine before I took the photos I posted.  After 50 odd years it was in nasty, crusty condition.

 

My 02 will never be confused as anything original.  It is M20 swapped, flared, and lowered (purists be damned).  I am leaning towards a 1/8" aluminum panel that screws in place.  It will have no connection to the sunroof track....easy on, easy off.  Not sure I will cover the aluminum.

[68gretchen]

8 hours ago, 66Vette said:

Toby:

 

Thanks.  You are right about the foam.  I tore off mine before I took the photos I posted.  After 50 odd years it was in nasty, crusty condition.

 

My 02 will never be confused as anything original.  It is M20 swapped, flared, and lowered (purists be damned).  I am leaning towards a 1/8" aluminum panel that screws in place.  It will have no connection to the sunroof track....easy on, easy off.  Not sure I will cover the aluminum.

I used 14ga aluminum with screws for attachment...works great.

Mine is a mishmash too, which is great because of the freedom it gives me to play by my own rules.

 

[66Vette]

68Gretchen:

 

Thanks, nice to see someone went down the same road.

 

Would you mind sharing a photo of your sunroof for inspiration?  

[slowbert]

After getting things back together on my restoration, it took a while to sort out and properly adjust the sunroof. 
 

I was a bit disheartened early on, but redoing to installation several times and working through the adjustments, the sunroof design is quite robust. 
 

Trust the engineers who designed it. They did a good job. 
 

In all my back and forth with the sunroof, I never had to get underneath the headliner.