Jalopnik: Porsche Cayman R announced at LA Auto Show

[marcos_eirik]

Same reason I find ANY weight bias a "problem", there should not be one. Also didn't they call the 911's a widow maker?

Why do you find a weight bias to be a problem? In most MR performance cars it's prefered to have a rear bias:

Ferrari 458; F: 42%, R 58 %
Lotus Exige; F: 38%, R: 62%
Ford GT; F: 43%, R: 57%
Porsche 997 GT2; F: 38,5%, R: 61,5%

It doesn't stop there either, even in performance oriented FR cars they pull off many tricks to get a rear biased weight distribution:
Ferrari 599; F: 47%, R: 53% (Same for the California)
Mercedes SLS AMG; F: 47%, R: 53%
Dodge Viper; F 49%, R: 51 %

The original 911 Turbo was labelled the "widowmaker", though that was mostly down to it's unpredictable, laggy single-turbo engine. On the other hand, lot's of other cars have earned that label as well...

Do they run against the Cayman at the same power-to-weight ratio or do they run against OTHER MR cars? I remember watching some race that had three different types of car. Stang, Porsche and the E46 M3, the Porsches were pretty much where their engines are

Well, let's see...

2010 ALMS GT-class was won by Porsche 911
2010 LMS GT2-class won by Porsche 911
2010 Le Mans 24h LMGT2 won by Porsche 911
2010 Spa 24h won by Porsche 911
2010 British GT Championship GT3-class won by Porsche 911
Also, they led the 2010 N?rburgring 24h for 23,5 hours...

... And that's just this year. Not bad for a car with an "inferior" weight distribution, or what?

 

[Nugget]

Sure, but it still shows that the car can be competitive against F/R and M/R layouts

Yep, and that's hardly surprising? One of the more entertaining rivalries in the GT2 class is between Porsche and Ferrari. Feel free to check my arithmetic on this, but it seems like the F430's front:rear weight distribution of 43:57 is actually closer to the Porsche's 39:61 than it is to a theoretical "perfect" 50:50 neutral bias. The Ferrari is an MR layout but they still chose to give it a pretty healthy rear weight bias.

Even the Cayman's 45:55 front:rear bias is almost halfway between a 911 and 50:50.

Maybe there is a benefit to rear weight bias after all? Or are the Porsche and Ferrari engineers just incompetent?

 

[Nugget]

Wow, I had no idea the Exige weight distribution was that dramatic. No wonder I like to drive them.

 

[prizrak]

Ferrari engineers just incompetent?

As a Lamborghini man I have always believed that.

Well, let's see...

2010 ALMS GT-class was won by Porsche 911
2010 LMS GT2-class won by Porsche 911
2010 Le Mans 24h LMGT2 won by Porsche 911
2010 Spa 24h won by Porsche 911
2010 British GT Championship GT3-class won by Porsche 911
Also, they led the 2010 N?rburgring 24h for 23,5 hours...

... And that's just this year. Not bad for a car with an "inferior" weight distribution, or what?

Now just imagine how much better it would be if it hadn't been RR

Yep, and that's hardly surprising? One of the more entertaining rivalries in the GT2 class is between Porsche and Ferrari. Feel free to check my arithmetic on this, but it seems like the F430's front:rear weight distribution of 43:57 is actually closer to the Porsche's 39:61 than it is to a theoretical "perfect" 50:50 neutral bias. The Ferrari is an MR layout but they still chose to give it a pretty healthy rear weight bias.

Again this is 911 vs <random MR vehicle>. We all know Porsche makes great cars, the Cayenne (while ugly as all fuck) is the fastest thing in its class, the Panamera is very good for something that huge, there is no question that Porsche knows how to make great (fast in this case) cars.

A rear-engined car brake harder and turn quicker and accelerate sooner than a mid engined car.

So that's why the 911 mantra is slow in fast out? Yes they can accelerate faster once they get through the apex but they generally brake earlier (there was a pretty large discussion about that on this forum at some point)

I am of the opinion that if Porsche took the Cayman and give it the same treatment as they did with the 911 (engine power, suspension, etc...) they would have a better (faster in all situations) car. Since Porsche doesn't seem to want to do that we may never know....

 

[equiraptor]

So that's why the 911 mantra is slow in fast out? Yes they can accelerate faster once they get through the apex but they generally brake later (there was a pretty large discussion about that on this forum at some point)

When did "slow in fast out" become the 911-specific mantra? This is something I've been taught from my first session on track and it's something repeated time and again, shared among drivers of all makes and models. It's a mantra we should all take to heart.

On most corners on most tracks, the driver should be accelerating before the apex, and generally well before the apex. If you're not rolling onto the throttle soon after turn in, you're doing it wrong (barring a few special corners). Like the "slow in fast out" mantra, this applies to every car, every layout.

I am of the opinion that...

I still don't understand the logic behind this opinion. You've mentioned weight balance, but it's been demonstrated that a slight rear bias is chosen by manufacturers over the 50/50 you supported. So what other logic do you have? Please, explain.

 

[prizrak]

When did "slow in fast out" become the 911-specific mantra? This is something I've been taught from my first session on track and it's something repeated time and again, shared among drivers of all makes and models. It's a mantra we should all take to heart.

Hmm... I only heard that in relation to 911's....

I still don't understand the logic behind this opinion. You've mentioned weight balance, but it's been demonstrated that a slight rear bias is chosen by manufacturers over the 50/50 you supported. So what other logic do you have? Please, explain.

Yes a rear bias will help acceleration (unless it's a weird RF car) but you would also have to take into account the polar inertia, too far back and your rear decides to see whats upfront, too far forward and you end up understeering off the track. I think that Porsche did great things with their suspension design that allows the 911 to have extra traction for accell and still retain handling but IMO the Cayman has a better balance between traction and polar inertia. Meaning that at same power-to-weight it should be able to stay more stable through corners than a 911 and also be easier on the driver since steering would be more neutral.

 

[ahpadt]

The 911 (even more so the GT3 and RS) is known to have the best steering of any sports/super/track-car.

 

[Nugget]

...but IMO the Cayman has a better balance...

You still haven't explained why this is your opinion. Why do you think that's true? Why do you think it's "better?" You keep stating this but never actually explaining why you think it's true. What makes it better? How? Why?

...at same power-to-weight it should be able to stay more stable through corners...

"More stable" isn't necessarily the goal. "Unstable" can be a lot faster than "stable." We see this in sports cars and also in fighter airplanes. Google for "F16 aerodynamically unstable" and read about how fighter jets are built for unstable flight because it makes them more maneuverable.

A less dramatic example than rear-weight bias would be setting your front alignment for no toe. You usually set a little bit of toe-in up front because it makes the car more stable at speed, but an enthusiast might choose to go with zero toe up front. It makes the car darty and fiddly (less stable) but improves turn-in and cornering response. "More stable" is a liability if performance is your priority.

"Neutral" and "stable" aren't really the focus for a sports car. I don't know why you keep insisting that they are.

 

[prizrak]

You still haven't explained why this is your opinion. Why do you think that's true? Why do you think it's "better?" You keep stating this but never actually explaining why you think it's true. What makes it better? How? Why?

I explained it in the post above.

"More stable" isn't necessarily the goal. "Unstable" can be a lot faster than "stable." We see this in sports cars and also in fighter airplanes. Google for "F16 aerodynamically unstable" and read about how fighter jets are built for unstable flight because it makes them more maneuverable.

I'm aware of how unstable modern aircraft is in order to achieve maneuverability and how many computers the F22 and the F117 require to actually stay flying.

"Neutral" and "stable" aren't really the focus for a sports car. I don't know why you keep insisting that they are.

You got your opinion I got mine.

Anyway I'm tired of this discussion, if Porsche ever releases a Cayman with same power as a 911 we will see who is right, until then just take this as my personal opinion.

 

[Nugget]

I explained it in the post above.

No, you just keep stating your opinion without ever explaining why you believe it.

You got your opinion I got mine.

My opinion is borne from the experience of over 50,000 seat miles in rear engine cars with close to 20% of that on road course race tracks. Yours seems to be based on little more than some unexplained theories and some incorrect facts you've developed about how these cars "should" handle.

until then just take this as my personal opinion.

I can live with that.

 

[prizrak]

My opinion is borne from the experience of over 50,000 seat miles in rear engine cars with close to 20% of that on road course race tracks.

I'm jealous (not being sarcastic)

 

[screwdriver]

Maybe there is a benefit to rear weight bias after all?

I can only think of traction. (And predictability through natural under-steer.)

Or are the Porsche and Ferrari engineers just incompetent?

I think, that the chosen weight distribution has more to do with the average Porsche or Ferrari driver than the engineers....

A few notes on the subject of weight distribution: The figure doesn't tell the whole story. What matters is where that weight is and how big a lever it has with respect to center of gravity. The figure also doesn't take down-force into considerations.

 

[Canuck]

Clearly you all seem to have forgotten the greatest benefit of the RR 911. If you lose control you'll almost always crash backwards, meaning airbags are less likely to go off, interior less ruined, and cheaper repairs.

(sarcastic yes, but true)

 

[equiraptor]

Cheaper repairs? Have you SEEN the cost of the GT3 RS engine?!?!

 

[Canuck]

Indeed I have, my old man crashed his '07 GT3 about a year ago and it would have been far more expensive had he crashed the other way around. Them engineers protect the engine pretty well lol.

 

[equiraptor]

Ah. The engineers didn't protect the Type 3's engine so well. One bump in a race cracked the transmission case (which is why our type 3 now has a type 4 engine and type 1 transmission). Thankfully, those aren't anywhere near the cost of the GT3 engine.