Doors and Road Noise

[Avly]

Just curious if anyone knows why high end two door vehicles such as BMWs and Porsches have doors where there is no frame around the window.

In my first car, an Integra 2 door, the door was completely framed including the window. This seems like the best solution as cars with doors that have their window framed all the way around seem to insulate noise and water better. I've noticed that even today cheaper 2 door cars such as Scion Tc and Accords have the side windows completely framed.

My gripe. Since my Integra I've owned a NSX, Porsche, and E46, these cars are significantly more expensive, but the side windows are not framed. In each car I've had problems with the trimming around the doors. Louder noise, and in the damn BMW, now that my car is 5 years old when I open the door too fast, the window gets caught at the top b/c that autoslide function is slower than the speed at which I push the door open. I really hate this retarded function btw. Can't they just frame the damn door so the window doesn't have to slide every single damn time, I open the door.

So does anyone know why high end 2 doors don't have framed side windows? It seems to be the more functional and elegant way to do it. Only reason I can think of is that in these cars they have convertible models and they want to cut costs by being able to share as many parts between coupe and convertible. Which is bullshit for coupe lovers to have to deal w/ some of the short comings of convertibles. Or is there is some performance reason the doors are like the way they are that completely eludes me?

[masmole]

It's actually more expensive to properly implement frameless door windows than with frames. The fit and finish tolerances at the factory are much higher for such designs and of course many cars like p-cars and bmws have to devise a slight electric window retraction during opening and closing.

There are many reasons why it's good: 1) reduced weight especially up high (lowered center of gravity), 2) style (the new $110k Mercedes CL vehicles have been using this design), 3) less chance of smacking yourself in the face with the upper corner of the door frame accidentally when opening/closing the door because the doors are much longer than in a sedans (I've seen it happen) 3) if done right, it doesn't create any more wind noise or filter out less road noise. I've noticed that my framed RS4 was much noisier by the A & B pillars than my frameless M3 coupe.

[masmole]

Originally Posted by Laszlo

But what I do miss, is the door frame and the little window that you can stick a cigar out of... Crap, what were those called?

I believe that's called a "ventipane", or sometimes referred to as a "quarter window", the former terminology more specific to those right on the A-pillars while the latter can be used for fore and aft.

I don't know how I know that... I'm not even old enough to have owned an old-school Caddy (which had powered ventipanes - whoa ballar!), nor am I a classic car collector.