OK, call it a spoiler, rear air deflector, wing, whatever... My question is to its purpose. But I want to know specifically if it is intended to direct air ONTO the rear window, or air ACROSS the rear window. If it were directing air onto the window, having the window open would give you air into the car. If it goes across the window, it would simply keep the exhaust from coming back in the window. Yes/no? I ask because I recently installed the air deflector on my '67 and in driving into work the other day noticed that the condensation on my rear window wasn't being blown off like I thought it would. I'm pretty sure I have it in the right spot, but I guess I could be off a bit. The curve of the mounts fit the roof perfectly in that spot. Anyway, just wondering what you guys thought.
I always thought they were supposed to blow air onto the window to keep the exhaust fumes from getting in. I could be wrong.
I'd heard that too, about the exhaust fumes, but if it's blowing the air into the back, wouldn't that also blow the fumes in?
I thought they were designed to keep the rear window clean (and the wind noise out) by bringing the vortex further back from the vehicle.
Keep it clean by direct airflow against the window, or over it? (I'm not sure I understand what you mean by 'bringing the vortex further back'.)
My understanding was that it is intended to redirect the air in order to clear the glass - in particular rain...
I meant that every object creates vortices when moved in an atmosphere like that on earth. These turbulences whirl about against the back of the object (in this context a car), slowing it down slightly (thus using more gas). The other side effect is that everything passing the top smacks onto the glass. The foil redirects the air flow, thus moving the turbulence in another direction. I thought that the vortex created by the foil is further back than without it, thus keeping the window cleaner and the wind against the window less (creating a low pressure zone). This can also reduce exhaust gases coming in through the window as the vortex is not hurled into the open window. @ Erik: I have the original American brochure of my car here as well and I see the same option, I also think it's not much more than a piece of rubber inside the tailgate
That's interesting that the airfoil on Chryslers were to bring fresh air in when the back window was open. I've heard a lot about trying to keep roadspray, etc off the back window when closed. I also did not know that the Chryslers had the rear window washer option. Ford/Mercury fullsize wagons in 71-72 had that option, as well. I don't know if that option stayed around after the 73 restyle.
Sorry to breathe life into this seemingly dead topic, but I installed a set of roof-mounted "Vortekz" generators on my Audi for many of the above mentioned reasons. They look something like this... Basically, they're a less obtrusive and more efficient way of manipulating the air flow in a similar way that a rear spoiler/deflector does. While the overall benefits are certainly debatable, the concept behind them is sound & proven, IMO. UberTeile
Those Audi things look like miniature truck clearance lights. Who cares what the spoiler does?...better to look good than to feel good. Obtrusive?, if you ask me rear spoilers are coo-doo. They're supposed to keep the back window cleaner and the exhaust gasses out. A mentally disturbed bird did a Kamikaze dive under my car and feathers came in the back window so how much it keeps exhaust gas out out I don't know.
