TheMystro

I can tell a difference with a front and rear spoiler/tail at 60mph. At 80mph, it is very noticeable. FYI...The front rubber lip and rear tail are designed to work together. Its both or nothing as far as Porsche is concerned.

theiceman

There is a graph someone posted a while ago. I bet Rusnak has it copied and saved
For me the tail discussion is an easy one. Anybody who flies a lot will notice nothing looks more like an aircraft wing than the profile of a 911. End of lesson

JackOlsen

I run a lot of different front/rear combinations, and I would say that the hazards of mismatched fronts and rears is generally overstated. It's something you should be aware of, but would have a hard time describing it as a safety issue at double-digit speeds. But then, I've gotten used to driving with a wing in the trunk and the spoiler bolted onto the front, or vice versa.

I've made very long drives with downright crazy aero. For illustration, here's a set of pictures that show most of what I've tried -- always driving to the track with some or all of the stuff attached.



























I've tested some nutty ideas, too.



But to answer the OP's question. You definitely should not pass on a car because it's got a tail. Simply buy a second-hand rear decklid from a dismantler and get it painted to match your car. Then you can either keep the decklid/wing combination for when (or if) you sell the car, or sell it to offset some of the costs of your new 911. They're worth quite a bit, when they're actual factory tails.

rusnak

I posted two graphs some time ago, along with the whole page from the Frere book "Porshche 911 Story".

I was reading it and came across Frere's explanation: The front and rear Porsche factory "Carrera" tails, when combined on the "high bumper" 911, decreases lift in direct proportion to the front/rear wheel weight bias. In other words, the arrangement is not so pitch sensitive.

There were other graphs shown on the airspeed/ lift cancellation of the duck, Turbo, and no tail. The 993 tail was mentioned briefly as well. The most effective tails were the Turbo and Carrera, as you can well imagine.

Some interesting notes were about the increased cooling of the tail, and that with or without the tail, the 911 is sensitive to lift/ vector changes in a crosswind, or when turning into a crosswind at a 45 degree angle. The crosswind cancels the amount of downforce from the front hood and windshield.

These pages in the book, along with the graphs and narrative made me decide to add a tail to my 911. The whole project set me back a few Ks but it was well worth it.

apperception

After PPI, my mechanic said it was a good one. Tail was removed, holes filled, and lid repainted. I'm very pleased as is wifey. Call me a sissy but I try to have my fun at under 110 mph.

Larry

Ed Hughes

You'll probably have to have your fun under 90, the tail kicks in below that. It is a personal choice, however. Of course, one person's fun may be different that the next-nothing like a light rear end at speed around a corner to get the juices flowing. That can be a lot of fun.

SiberianDVM

Is a ducktail effective at DE speeds?

Ed Hughes

Yes-any tail will cancel the lift created by the airfoil shape presented by the 911's silhouette.

SPDADCT

During a track tour on Porsche day at Fontana, while accelerating hard at 108 mph I felt the car lift in the rear. Enough for me to back off throttle and take it easy. Coming back after several laps, one of the PCA old timers said "You need a whale tail on that car if you wanna have it on the track". I couldnt agree more and going with a 964 Turbo S wing.

dshepp806

Anyone plots/data on the standard Carrera Wing vs this ducktail thing...?

I'm thinking "shape" has much to do with it....

Best,

Doyle

Ed Hughes

The very first tests of any wing on a 911 were the duck vs std lid. That mag article showing the lift of the stock and defeat of the lift with the duck has been posted a few times.

irobertson

I didn't post this originally, but I had saved a copy.

Frances325

I actually think the cars with the FACTORY TAIL would be better to buy if you plan on deleting the tail. The reason is that to buy all that stuff and add it later, you'd be spending easily a few $K on the total project, with all used parts. All you'd have to do is to save the old lid and tail, have a used lid painted to match and remove the right side lid strut.

kevinr1247

I never liked the look of the tail because I thought it ruined the classic "line" of the 911. Then there's the terrible unsexy E.T. style brake light. I ended up doing what was suggested in this thread, that is, buy a decklid, get it painted.

If you buy a used decklid I would make sure that you verify that it never had a tail bolted on to begin with. I went through one place initially that filled the holes and primed the lid but the work was terrible.....had to send it back which was a PITA. LA Dismantlers had one in good condition and I went for that one instead.

I think total I spent $300 for the lid and another $200 to get it primed, painted and buffed. I was impressed how close the body shop matched the diamond blue metallic. Then I fit it on the car. It was really easy. I ran into a bit of trouble finding the short T-Bolts to hold the grill but I ended up just buying six long bolts and cutting them down to fit. Voila.

I did leave the front spoiler on.

rusnak

I for one am stunned at Jack Olsen's ingenuity. Holy cr*p!!