The 944 has a much larger wing than the 924. Is there any advantage to installing the larger wing?
I recently read about Porsche experiments with the 911 spoiler and wing. It sounds like the front spoiler and rear wing work together to creat a balance of down force on the car. Messing with one or the other may change the aerodynamics for the worse or better. Just curious if anyone has any knowledge about why the 944 came with a larger rear wing and if it would be advantageous on the 924.

 

About to put a rear wing from a 44 on a 931, I'll let you know.

 

Great, let me know how it goes. I see we're neighbors too.

 

"... Just curious if anyone has any knowledge about why the 944 came with a larger rear wing and if it would be advantageous on the 924"

Yes... the 924S does not need such a large rear spoiler, because the lack of fender flares give the car superior aerodynamics (especially at the back).

The main function of the spoilers in both the 924S and the 944, is to reduce the overall drag co-efficient (and not just to keep the rear end down). There is an optimal spoiler size for any car.

-MAS

 

Thanks for the info. I've been reading Paul Frere's book about the developement of the 911. The H series air dam/spoiler reduces total lift at 152 mph from 397 lbs to 37.5 lbs. Pretty impressive figures. The improved 911 spoiler reduced oversteer and tendency to aquaplane. It would be worth changing over to the 944 spoiler for those improvements.

 

You might want to think about the carrera rear bumper too, this is much larger to help with downforce as the air slipped over the rear screen.

 

When driving in the rain at highway speeds, about 70 to 80 mph, I notice that the rain on the rear window doesn't get blown around at all. Doesn't seem like that wind gets to it. Likewise the water that gets onto the rear spoiler seems to sit in place except for the last 1 inch where the water seems to be blown off. That suggest that only the last inch of the spoiler is getting any air on it. Does anyone with a 944 have an observation about rain on the rear window and spoiler? This is pretty unscientific, but should give a hint as to what the wind is dong back there.

 

Note too that if you put replace a 924 turbo rear spoiler with a 944 rear wing, you'll increase drag. Roughly speaking, each spoiler is 'tuned' to the car it was built for.

 

"Note too that if you put replace a 924 turbo rear spoiler with a 944 rear wing, you'll increase drag. Roughly speaking, each spoiler is 'tuned' to the car it was built for."

Exactly! Porsche did not put the smaller spoiler on the 924S because it was cheaper.

-MAS

 

I have the greatest respect for Porsche engineers. That's one of the reasons I own a Porsche. There is an evolution in all the Porsche lines. The early 924 had no rear spoiler at all. Then as performance inproved the 924S got a spoiler. The 944 appeared with approx. 50% larger spoiler. I am curious why. I agree the aero dynamics are likely to be different because of the flaired fenders of the 944. Is there a source of information available regarding the developement of the 924 and 944 series? I have one of Morgan's books and Vivian's book as well. Frere's book about the developement of the 911 is very enlightening. Does the 924/944 have such a book? Thanks.

 

Remember though... the 944 (with the large spoiler) appeared in 82... four years before the 924S. It wasn't simply evolution in spoiler size. Porsche deliberately put a smaller spoiler on the 924S because of the different aerodynamics of the car (especially the rear).

I'll have to double check, but I think I read about this in Michael Cotton's Porsche 924/944 book.

-MAS

 

...true MAS, besides, if the evolution of a spoiler meant that the spoiler got bigger, then late 80's 944's would've looked like (gag) this:



Heh heh.

 

Thanks for the info. I'll see if I can find a copy of Cotton's book. No, I am not likely to change out the spoiler on my 924S I like the way it looks and functions. I'd be more inclined to put a 968 style spoiler on anyway.

 

Ack! Rice!(holds up cross).

My brother has a 931, and he recently replaced the stock spoiler with a 944 one, that came from his other 924, which I am buying in a month or two. They really don't make much of a difference in the aerodynamics, they just diffuse some of the air exiting the car, barely lowering the drag co-efficient. Downforce isn't really noticeable until 80mph anyways.

But damn, it just looks better with the 944 spoiler.

 

If someone with a 924 is interested, I've got an aftermarket 924 wing which is a near replica of the 944 wing, only its made in a hard plastic with a sprayed on rubberized coating. Comes with hardware to clamp to the edge of the window glass. The unit has a small crack on one corner at the casting seam, probably could be patched easily with fiberglas. $50 plus shipping and I'm happy to get it out of my garage.
Eric