i own an SRT Jeep, which is stock other than a Corsa exhaust. my pop owns mk2 Cayenne Turbo, all stock.

by the magazine numbers, its accepted wisdom that while the Jeep is great from a dig, it simply falls down at higher speeds (say above 100mph,) where the much more powerful Cayenne comes into its own.

subjectively, this is exactly how they feel as the Jeep just leaps off the line thanks to gearing and the zero-lag NA response, where the Porsche is longer geared and has that typical turbo "rubber band" acceleration feeling. but on the highway and at higher speeds, the Porsche just pulls like a freight train.

so my butt dyno confirmed everything magazines had said.

here's an old video of the Jeep i took (before i got the Corsa): http://www.youtube.com/watch?v=c7AGbozuPVs

and here's an old video of the Cayenne: http://www.youtube.com/watch?v=1FmwSfVar9I

for good measure, here's the same Cayenne vs a buddy's ML63: http://www.viddler.com/explore/hesperus/videos/6/
note the speed being called out by the driver of the camera car is KMH, not MPH!

now over the past few months i've tested over 50 cars with my VBox GPS, mainly their 60-130mph times. what i've found-- not too surprisingly-- is that the very bad conditions (90 degree heat, 80%+ humidity) and horrible gas (approx 91 octane) here have a massive effect on the cars' performance. times over here are nothing like what folks in the U.S. are getting.

what WAS a big surprise though, is that my Jeep was noticeably quicker than the Cayenne to 130mph, the gap being a massive 1.4 seconds. my guess is that the more "honest" horsepower from a big displacement normally aspirated motor is less affected by bad gas than a more highly stressed smaller displacement forced induction motor. by the specs, the Porsche's specific output is 104hp/liter, to the Jeep's 69hp/liter, more or less.

i'm pretty sure our Cayenne is running healthy, as it kept up (after the initial jump) with the ML63, which has been tested to be about as fast, AND a friend's older first gen Cayenne Turbo was slower again still than our car.

one more thing... all the VBox 60-130 testing i've done over the past few months (and i've tested well over 50 vehicles, ranging from a slowpoke Jaguar S-Type V6, to a Lamborghini Murcielago LP670-4 SV, to a stupid fast BMW S1000RR sport bike,) is that the butt dyno is a huge liar! cars that "feel" crazy fast aren't always as fast by the #'s, and cars that don't feel that fast, turn out to be right at the top of the list.

just thought i'd share the results, as i was quite surprised.

Dude I wish we had a highway like that here in the US. Where are you located?

Our Jeeps aren't that bad in high speed. But the Cayenne has longer legs.
I would say that our Jeeps are quicker up to 125MPH then the Cayenne will start reeling us in.

On highway speeds you're toast , I thing your only chance to take it is from 0-100 MHP .. Unless you get some minor Mods . CAI/Tune

Notice how much better the Jeep sounds than the Cayenne.:cool:

Notice how much better the Jeep looks than the Cayenne? Never been a fan of that car.

here's the GPS.

http://farm5.static.flickr.com/4100/4751684911_9c7c70705e_b.jpg

the Jeep and Cayenne were both driven by me. the mk1 Cayenne belongs to a friend as is there for reference. however way you cut it, the Jeep is quicker, and i find it difficult to see how the Cayenne would catch up (the graph ends at exactly 130mph).

its possible i had a tailwind in the Jeep during that run. though i've done several runs in both cars and on average, the Jeep is consistently quicker.

my explanation? our gas... at best we have the equivalent of CA 91 here. that sophisticated German motor simply needs really good juice to deliver its full potential.