irobertson

I have an 88 coupe with no tail.
I have been thinking of getting another deck lid with the correct tail, or a deck lid with a duck tail.
I prefer the look of the duck tail, but I'm curious about the aerodynamic benefit the duck tail has in comparison to the Carrera tail.
It would seem to me the proper Carrera tail would work better simply due to it's greater surface area.

Anyone have experience with both types of tails?

cheers

Daniel Dudley

Ducks are about 2/3 as efficient as a whale IIRC. I don't think either create downforce so much as negate lift. Lift is a bad thing, IIRC. I have been looking at both for so long that I think they both look good to me.

Only one would be proper on an SC RS. Either is correct for an IROC replica.

rusnak

Paul Frere's book "Porsche 911 Story" has a comparison between no tail, duck, Carerra, Turbo, and the later moving tails. The Carrera tail is more effective than the duck, and even more effective than the folding tails. I have noticed better cooling at speed since installing mine.

Edward

Yup, Frere's book covers this well ...not to mention is a great read. Moreover, if you add a carrera tail, you must add the front lip for aero balance. This, too, is borne out by tunnel testing as per Frere's book. I can't remember whether the duck tail requires front aero compensation, however.

BTW, personal side note: I think an 88 would look far better with a Carrera tail ...the duck is nicer on the long-hood cars ...IMHO anyway

Edward

Ed Hughes

Ducks look just as good on any car up to '89, even lowly Targas.

I've even seen a 993 with one, and that looked great too.

irobertson

Thanks all,

I'm also planning on new front and rear bumpers, fiberglass yellowbird style or IROC, not sure yet.
I certainly going do something for a front lip whether it is part of the bumper or not.
Looks like I have to get a copy of Frere's book.

cheers

mck911

+1.

Todsimpson

JackOlsen

Carrera and Turbo tail are different. But the Carrera tail is slightly better than the duck, both in terms of reduced lift, and also (I'm pretty sure) in terms of reduced drag.

The ducktail looks better, to my eyes.

rusnak

Aesthetically speaking, I think the duck tail looks awesome, especially on 70's Porsches. Something about it suggests sophistication without gaudiness. I'm not in love with my Carrera tail, even though I spent about $1.4K or so total installing mine.

I don't think a duck would look good on my impact-bumper 911 though. To me, the only choice was a Weissach coupe tail, or a Carrera tail. And the aerodynamics of the Carrera tail were superior in my opinion. It moves the low pressure area further up on the rear of the car, and takes advantage of better air intake flow.

I think our 911s probably look better with no tail, but after reading the Frere book, I couldn't get that aero data out of my mind. I just had to have better stability, and I'd do anything to get better cooling.

irobertson

Well Jack, your whole car looks better to my eyes. :-)

cheers

Edgy01

When I had my last air-cooled 911 type auto I ran a 934 RSR tail on it. It looked like this. It's a great tail, and more effective than the simple Duck Tail. I liked it for the aerodynamics but also appreciated the looks of it,--not as massive as the later tea-tray whale tails. It was also featured on the first 930 Turbo-Carreras in 1977, but later replaced when they had to fit an intercooler onto the engine when they moved up to 3.3 litre engines.

cmoss

Here, and I'd like to see a design study of an old school ducktail on a 997.

rusnak

Jeez, that is a good looking car, Cmoss. From that angle, the sightlines converge at the rear around the tail lights. The duck tail just looks surprisingly good.

irobertson

Thanks Dan & Chris.
Both very nice looking cars.

Is this the car in the pic Dan?
http://www.conceptcarz.com/vehicle/c...0&iDNumID=1917