964 wing - aerodynamic benefits or cooling only?

AndrewMac · 04:05 AM

I've not been able to find any data on the benefits of the 964 retractable wing in reduction of lift and particularly versus a Carrera and duck tails. I know some like Jack Olsen have converted early narrow bodies to the retractable wing. I'm inclined to replace my Carrera tail n my SC with the 964 lid to clean up the lines on my targa.

My driving is standard around town and interstate. Maybe some track time this summer at Mid-America. I'd like to preserve some benefit of the reduction of lift but the threads I've read don't speak to the retactable wing's net effect in this regard.

I'm a liberal arts grad so please don't force me to unearth my slide ruler. I don't really know how to use it...

javadog · 01-29-2006, 06:28 AM

Paul Frere talks about this a little in one of the later editions of his book "Porsche 911 Story." It's hard to say how much the rear wing alone will reduce the rear lift, as Porsche had some other things they did on the 964 cars, but they have less drag and less lift than the earlier cars. Lift is pretty close to zero. Remember, the 964 has an undertray that raises slightly at the rear as well as directing the output of the engine fan in a different way, both of which can affect the lift figures. I have to believe you wouldn't be any worse off with the retractable rear wing than a Carrera tail. The duck tail is not as good as the other wings.

JR

Bill Verburg · Bill Verburg's Garage

The fixed RSA tail is considerably more efficient at reducing lift than the Duck-tail, the movable wings as used on 964 and 993 are roughly equivalent to the Ducks.

The cooling aid comes from increased pressure at the engine compartment air intake.

AndrewMac · 01-29-2006, 08:34 AM

So I remove the orginal Carerra tail and install the 964 lid with wing, wire up the wing to function on demand via a switch and I'll be able to have equal benefit of reduced lift from this tail? I do notice the Carerra tail seems to make the car more stable a 90+ and especially if there are strong cross or head winds on public roads. I plan to keep the original lid and tail soI suppose I can ipso chango.

I want cleaner aesthetics and to visually lighten the rear of the car. And the Carerra tail attracts all boy-racers, ricers, angry rednecks, and cops.

Does anyone have first hand experience going from Carrera to retractable wing?

Bill Verburg · Bill Verburg's Garage

Quote:

and I'll be able to have equal benefit of reduced lift from this tail?

For street and lower speed use it's mostlly a non issue.

I did the opposite, went form the moveable to the fixed on my 993 for improved track performace and lighter weight.

The fixed tails are definitely more effectice than the ducks or moveable , the higher the speed the more so.

Wil Ferch · 01-29-2006, 02:52 PM

Look what I and other say here, not 100% conclusive but a good read for thought nonetheless--->

Track experience w/ C2 spoiler on earlier car

-Wil

masraum · 01-29-2006, 04:28 PM

I seem to remember reading that the 964 tail wasn't as good at reducing lift as the fixed tails, but then with the 964 body changes it didn't have to be. So I believe, yes, it will help, but not as much.

AndrewMac · 01-29-2006, 10:11 PM

Thanks for the input. Not exactly what I expected. I didn't take into account that maybe the 964 doesn't really need so much surface area to mitigate the lift at speed.

Maybe the DUCK is the better way to go. Hmmmm. Now I'm not sure. Paralyzed by ignorance and fear. Someone else have some anecdotal evidentiary hearsay type infotainment?

masraum · 01-29-2006, 10:13 PM

Get the duck.

bigchillcar · bigchillcar's Garage

quack..

randywebb · 01-30-2006, 12:12 PM

How fast do you usually drive?

How does the front end feel at those speeds?

AndrewMac · 01-30-2006, 08:15 PM

I spend a good share of the time on the interstate and two-lanes. My targa has the rear wing and front spoiler from the factory in late 1981. I like the way it handles both front and rear as it is set up. I also have a 1978 targa from which I removed the turbo tail someone had added. The 78 is set up with chin spoiler and no tail and certainly the 81 is more stable, less prone to buffeting from wind and better in rain at speed. I know the 78 needs a tail of some sort to balance the aerodynamics or I should remove the chin spoiler.

I just get really self-conscious about the attention the fixed tails attracts. It just bothers me. I love the cars and drive them every day but I want to keep my head low while keeping the stability of having a tail.