Whale vs. duck?

[FastCarFan]

I have seen a lot of posts about whale-tails & duck-tails, but most are related to the appearance of the tails. I am curious about the relative effectiveness of the two tails.

I would assume that Porsche's knowledge base increased over the years & it switched to the whale at least in part because it is "better". Maybe it provides more downforce with less drag? Or the same downforce with less drag? That is what I would guess. Am I correct?

I realize there are multiple versions of the whale-tail, turbo vs. non-turbo, etc. I have an '88 Carrera with the optional whale-tail. If I switched to a duck-tail how would the performance of my car be affected? What about the weight difference between the two?

As always, thanks in advance for your replies. I know someone here has the answers to my questions.

[RWebb]

whale is better than duck - search on those terms for many lengthy explanations...

[old man neri]

The better question is what kind of driving are you doing? Depending on the use of the car you may not notice any difference.

[snbush67]

Also what car? Do you have a front spoiler etc.

[FastCarFan]

Originally Posted by old man neri

The better question is what kind of driving are you doing? Depending on the use of the car you may not notice any difference.

Fair question. Mostly weekend drives on winding roads through the woods, freeway trips to Mid-Ohio & about 4 track-days per year.

And I do have the front spoiler.

I will search. Thanks.

[RSTarga]

Whale has less drag, weighs more. Both improve the aerodynamics in a big way.The duck looks better on the earlier cars. You need some sort of spoiler on the front to balance otherwise you'll get front lift at speed. If you can get a copy of Paul Frere's book all the aero figures are there.

[stormmaster]

i doubt you will notice any difference....now if you paint your car blue....we all know how fast that color is.....

[FastCarFan]

I agree I likely wouldn't notice any difference. The question was more out of curiousity than an attempt to shave 2 seconds off my lap time.

And, no, I am not painting my car blue. Red cars are faster. Everyone knows that!

[old man neri]

Please read this. It might help you, it also has graphs showing the effectiveness of each tail vs speed.

Remember to thank Ian for his hard work
-matt

[Doug&Julie]

Originally Posted by RSTarga

Whale has less drag...

I could have sworn I just read an article that stated the miracle of The Duck is it increased downforce without adding drag...

[911st]

Matt's link is gold.

None of the Porsche spoilers actually creates any positive down force, they do reduce lift. At 60 it is not significant, 90 starts to do a little, at 150 the 3.3 tail reduces lift by about 250 lbs on a rear end that weighs about 1800lbs. A duck is about half that.

I do believe some of the spoilers do "spoil" the air flow and reduce drag to.

[Bill Verburg]

Originally Posted by FastCarFan

I have seen a lot of posts about whale-tails & duck-tails, but most are related to the appearance of the tails. I am curious about the relative effectiveness of the two tails.

I would assume that Porsche's knowledge base increased over the years & it switched to the whale at least in part because it is "better". Maybe it provides more downforce with less drag? Or the same downforce with less drag? That is what I would guess. Am I correct?

I realize there are multiple versions of the whale-tail, turbo vs. non-turbo, etc. I have an '88 Carrera with the optional whale-tail. If I switched to a duck-tail how would the performance of my car be affected? What about the weight difference between the two?

As always, thanks in advance for your replies. I know someone here has the answers to my questions.

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