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Discussion Starter · #1 ·
I'm not a technical kind of guy, so I need someone to explain to me how a GTI could go through climbing esses faster than a Cayman S with PDK. This is according to Car and Driver in their Lightening Laps, in sector two.
 

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I'm not a technical kind of guy, so I need someone to explain to me how a GTI could go through climbing esses faster than a Cayman S with PDK. This is according to Car and Driver in their Lightening Laps, in sector two.
Without seeing the data, here's a wild guess:

The GTI is a FWD car with the majority of its weight on the front axle. When going through "Climbing Esses", there will be weight shift towards the rear axle - possibly providing a balance that makes better use of all 4 tires' grip. Since the Cayman already has ~55% of its weight on the rear axle on flat ground - it would have much more rearward weight bias going uphill. Might throw the balance in favor of the GTI in this limited example.

How do the numbers look coming down the hill? If my hypothesis has merit, the Cayman should be much faster than the GTI there.
 

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The question is a good one, and the responses above may be on target. The GTI had the slowest lap time of all, and was among the slowest three in all the other sectors. But it beat six other cars through the uphill esses (sector 2). C&D comments also indicated the GTI powered and tracked very well through the esses. Times through the two sectors that have some downhill to them (sectors 3 and 5 begin as downhills, but then flatten out) weren't the GTI's forte (second and third slowest times), consistent with grant's hypothesis.

The GTI's charge through the uphill esses may still be somewhat surprising. The GTI weighs a few pounds more than the Cayman S, gives up 120 hp to the CS, and enters that sector 8 mph slower. Yet the GTI's average speed through the sector is .4 mph faster. It beats the CS through that sector by .1 second; 9.3 seconds to 9.4 seconds. Good for Mighty Mouse.
 

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Discussion Starter · #5 ·
I don't know when the downhill begins on this track, but it seems as though Jim does. I'd like to thank all of you for your answers.
 

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Having owned one in college, I have a real soft spot for GTIs and may own another yet. However, I find this (section) data hard to believe. Transferring weight off of the drive wheels under acceleration is a fundamental disadvantage to front wheel drive cars, generally causing understeer. Factor in power-to-weight etc....
 

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I had a 2007 GTI with the turbo 2.0 liter motor. Max torque comes on at 1800 rpms and it's a flat line of torque to 5,000 rpms when she runs out of breath.

The motor was nice (if you like turbo charged power delivery), but the rest of the car was an electrical and rattle trap nightmare...
 

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I have a 2007 Gti MKV as a daily runner with Revo stage 2 tune and controller plus Evoms air intake and AWE turbo back performance exhaust plus I lowered car 2 inches with Eibach springs and upgraded sway bars front and back!!

I also have a Cayman S with Evolution intake, tune and Miltek exhaust! I love the Porsche but can tell you that the Gti can give it a run for its money in more ways than one! Obviously Gti is not stock and I have done a lot of work to VW! The CS is definitely more refined in so many ways versus the VW. I am not at all surprised with the outcome of the two cars.
 

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I've driven the climbing esses at VIR many times, and looking at C&D's spec sheet you see the variance is minimal. But notice the Cayman S comes into the section at 114.3 mph, the GTI at 106.1 mph. So the Porsche is coming into that section at 8 mph more speed but exits .2 of a mph slower than the GTI. So through the section the Cayman LOST 14 mph in speed while the GTI lost 5.5 seconds.

So the question becomes why did the Cayman loose that much?

I've driven probably 15 different cars through the Climbing Esses at VIR, including M3's and M5's, Porsches, an Acura NSX, all sorts of Audis, Mazdas, and a Formula 5000 car. The worst car of all to go into the section was my 1996 993 C4S "Angelina", which wanted to swap ends on its softly sprung rear as it made its way up the hill.

Two variables I can think of. One is the suspension. A stiffer car in general will get through the climbing esses. The Left / Right transitions really take a toll on softer suspension cars. Most Porsches from the factory have a fairly soft ride setup, and the GTI may simply have a much stiffer suspension which would account for its maintaining its speed. Install a set of PSS9's on that Cayman and I bet most if not all of that 14 mph speed drop would evaporate.

Secondly, it could be tires. We don't know what kind of rubber is on either of the test vehicles and that can also be a factor in that segment of the track. When you lose your grip, you're all done going fast.

Section 5 (Hogpen) at VIR is the downhill that separates the men from the boys. You can see in that section the VW doesn't do so well.

C&D's article on that is entertaining, but it really doesn't give you enough of the variables to determine why some of the data shook out the way it did.
 

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Re what Jeff said, Car & Driver said: "The front-drivers we had at VIR suffered from prevailing understeer and required all the finesse our inner Fangio could summon." ...
"Despite persistent understeer, the GTI never felt unsettled or out of its 'happy' operating range. It was calm and collected when climbing through the esses, with its 2.0-liter turbo four working hard and the steering communicating telepathically to the driver -- an unusual trait for a front-drive car."

C&D also said that the new GTI was 5.8 seconds quicker around the course than the nearly identical 2007 GTI they tested in the 2006 Lightning Lap.

It still seems to me that the CS should have the advantage in the uphill esses. I've been thinking all along that my times through that sector in the CS beat my previous times in the RS America more than anywhere else on the course.
 

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anyone surprised to see the CS post up an identical time to the Carrera S? Next year we'll get to the the spyder post up a time as well. I would think with a more track oriented setup and less weight we should see a faster time.
 

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anyone surprised to see the CS post up an identical time to the Carrera S? Next year we'll get to the the spyder post up a time as well. I would think with a more track oriented setup and less weight we should see a faster time.
having driven the 987.1 and the 997.1 extensively back to back on the track this bit seemed the most shocking to me. Oh, and the M3's time with cup+s was barely better than the last one tested with DCT issues but also beat both of the porsches.
 

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Cayman ties 911 in Lightning Lap battle.

According to the latest Car and Driver, around VIR's Grand Course configuration the Cayman S is just as fast as the 385 BHP 911 Carrera S with a 3:05.8 lap time. So with Caymans matching 911s on track with weaker engines, can we please get a serious motor in the 987 chassis? The underdog deserves to be on equal footing with the 911, the lap times prove it.
 

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Re: Cayman ties 911 in Lightning Lap battle.

According to the latest Car and Driver, around VIR's Grand Course configuration the Cayman S is just as fast as the 385 BHP 911 Carrera S with a 3:05.8 lap time. So with Caymans matching 911s on track with weaker engines, can we please get a serious motor in the 987 chassis? The underdog deserves to be on equal footing with the 911, the lap times prove it.
Merged your thread into existing thread on this topic.
 

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Sorry!

Didn't realize we were discussing it already, I thought I checked. VW aside, I'm surprised more people aren't paying attention to the fact the CS and 911S tied. There's a pretty big difference in power there, and price.
 

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Re: Sorry!

Didn't realize we were discussing it already, I thought I checked. VW aside, I'm surprised more people aren't paying attention to the fact the CS and 911S tied. There's a pretty big difference in power there, and price.
If you download the Lap Comparison spreadsheet, you'll see that the 997.1 Twin Turbo also posted the same time as the Cayman S and 997S. Only the GT3 (997.1 version) was faster, by several seconds.
 
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