djcxxx

On general principle I am opposed to additional complexities and gizmos, but the RWS has the effect of making the overly large 991 feel like a smaller and more nimble car and for me that outweighs the lost ability to play with the rear end, at least in the majority of driving situations that I deal with. FWIW when I was reading the section in 000 suggesting a modern Club Sport I thought the 370HP was not really enough because Porsche would never be able to take out enough weight to make the concept work. Back in '88 our local Porsche dealer had a white CS and it sat for months.

Alan Smithee

I don't classify any 991 models as 'investment grade'. I was pointing out that the landscape is very different now from what it was in 2009.

stout

Great points, and I question the value of "drift-ability" in any of these cars for anything other than drift events and internet videos. Do it on the street and it's irresponsible...do it at a track day (at least, any track day I've been to) and you'll get black-flagged (at best).

Thought on the F22.2 was less about getting weight out to make the car faster and more about the principle of less is more and even the base 991.2 is already quick enough to be a joy. The T sure delivers on the concept�and remains with 370 hp. It will be interesting to see if it meets the original Club Sport's fate, but my guess is no. "Porsche" as a brand is in a very different place now than it was then, and the world seems to wait with baited breath for any model that might be considered "special" or focused, etc.

djcxxx

By the way, your alloy wheels on the F22.2 are far and away more attractive than anything Porsche offers currently.

Alan Smithee

Yup...in 1988 you could also find new E30 M3s collecting dust in the back lot of every So Cal BMW dealer...

Petevb

Though rarely experienced, to me the difference at 10/10ths (which I can really only access at the autocross) is striking, though admittedly I'm convoluting generations (997 GT3 RS vs 991 GT3) with rear wheel steering. That said I need to anticipate and chase the 997's rear end far more, where the 991 tends to "do it for you"... right up until it doesn't and all hell breaks loose. It's a very different game on the limit, enough so that I wonder if I won't end up coveting my friend's 997 GT3 RS long term... even as I beat him with my 991.2 GT3T. We shall see...

stout

Thanks!

They could so easily be offered by PAG. They are, after all, just 911-50 wheels with the spokes in one color (white, light silver, black, gray, etc). Only thing PAG would have to make is the 911-50 rear wheel in an offset for the NB 991.

Almost wonder if one of the custom forged wheel companies out there could reverse-engineer a pair of rears and make forged rears available as a group buy to match factory fronts�if the face geometries could be nailed it would be a great-looking wheel for NB 991s.

Archimedes

True, but you can have some fun sliding a car around a bit on the street without going into full irresponsible Chris Harris drift mode.

155

^^^


I don't get the negative feelings for the T when it's been dialled in with nice options at a discounted price. With a GIAC chip produces @ 400 whp.

randr

Pete, honestly I think you're over analysing this.

RAS behaves in a very consistent way - you won't notice it from a feel point of view (on track) but you will notice it from a turn in and speed through the corner point of view.

Basically, on the line it allows you to carry more corner speed as the wheels are pointing the same way through high speed corners.

In essence the limits are raised, because of this.

Nontheless if you overcook it (approach speed was to fast or over tightening across the line) - you will still reach the friction limit of your tires (contact patch) and if you breach it, spin.

Its is no different to any other Porsche other than the limit this occurs at is higher. The car is not doing it for you e.g. its not intervening.

Petevb

randr,

This reminds me of your views on turbo-lag: that it's immaterial on modern cars such as your own. And for the way you drive that may well be true, but you'd prefer not to admit that for the way others drive there is an impact that can be significant.

Rear wheel steering is similar- if you're driving in such a way that you're not losing the rear end it's quite possible you won't notice a difference. If you are driving on and over that line, however, the difference is substantial. I'll try to explain why:

First, rear wheel steering does not inherently increase the grip of the car or the rear tires mid-corner. The rear tires don't know or care if rear wheel steering is angling them by a degree and a half relative to the car or if the whole car is rotating by a degree and a half. From their point of view the effect is identical: they are operating at 1.5 more degrees of slip angle to the road.

From the driver's point of view these two things are different however. The car without rear wheel steering is rotating slightly, which the driver experiences as mild over-steer, while the car with rear wheel steering's rear end is more faithfully following the front. Both cars have the same absolute cornering limit, but one is much tidier getting there: no need for the driver to subtly unwind lock to counter the mild over-steer, etc (what I mean by the car "doing it for you").

Many drivers will never realize the difference or go past this point, but let's consider what happens if you do. Wide modern R compounds peak in grip beginning around 4 degrees of slip (depending on the surface, etc, etc), after which they fall off. Without rear wheel steering it's relatively intuitive: you're feeling two degrees of over-steer, so your seat-of the pants lets you know you're roughly halfway there. With rear wheel steering, however, the system is masking that same slip: you're still half way to breakaway yet you feel almost nothing. This is much of reason some feel the feedback is non-linear and artificial.

From a simpler perspective you've got around 4 degrees of warning before you're chasing the tail of the car in a non RWS car, and that's nearly cut in half to 2.5 degrees with RWS, with some of the early warning feel drivers cue on masked by the system.

Hopefully you can see from the above how when driving within the tire's limits with system could feel great and predictable (and be less work for the driver) while violently approaching and exceeding the tires limits could feel like a different ball-game.

Like most things RWS is a trade-off. It has huge benefits in transition- it takes time for a non-RWS car to adopt the required tail-out attitude before it can generate the same grip, then more time to gather it up and go the other way. Thus RWS cars are far quicker in initial corner-entry, slalom, etc, and don't get subtly "out of shape" nearly as much. As mentioned they are also easier (or at least less busy) below the limit, with the RWS taking care of much the correction the driver would otherwise need to.

The above is obviously a theoretical explanation. The proof is in the driving experience, however. If you ever spin, or nearly spin, a 991 GT3 back to back with a 997 GT3 RS (ideally on the same tires), I feel certain you'll easily feel the difference in the way they communicate before breakaway from behind the wheel. I find it far from subtle, no analysis beyond "what just happened?" necessary. I'd expect most drivers would hit that "nearly spin" zone where it's easy to tell around twice per pass at the average autocross if they can carry nationals level pace.

So again, I get that you might not notice the difference. Just don't assume that means there isn't one.

StudGarden

I get what Petevb is saying. What I’m concerned about is essentially losing half of an already narrow “seat of your pants” sense of when you’re about to lose it. The only payoff seems to be for really ridiculously awesome drivers who want/need to go very deep, very often, into that very narrow window trying to milk an extra hundredth of a second out of it or whatever.

Ok cool for them. I guess, despite that few if any of these dealer bought street cars will ever truly be raced by professionals who could even in theory earn more than they spend on doing so but whatever. Anyone whose really that good wouldn’t ever buy one of these for that anyway; they’d be driving something WAY better and more expensive, paid for by teams and sponsors in the first place.

But for 99.Something percent of all T/S/GTS/GT3 drivers, even including hard core trackers who crave the razors edge and have no issue with risking balling up a 100-200K car in a tire pile in search of that hundredth of a second in turn three, I’m still not seeing the advantage:risk-cost return, and that’s saying nothing about the IMO even more important and essential (from a driver’s perspective) loss of half of the “seat of your pants” feel, especially for what is marketed and extolled as a “driver’s/purist’s” car in the first place.

I’m still trying to learn about this. But for now I see it as a huge net negative that provides an on paper lap time advantage at the cost of feel and fun and even safety until you get uber awesome at it at a level few ever will.

So from that perspective, it seems like the main/only reason to spec it in a car like this is because the next buyer will either grossly overpay for it or that you’ll be disproportionately punished for not speccing it (either way).

Loess

Interesting discussion. I think you will get that tight turning sensation with RWS more often as a normal driver than you will feel that last little bit of warning at the limit of over-steer. The feeling with RWS is not artificial, is real mechanical change.

What about an LSD? It is a mechanical devise built into the car to alter how it drives and feels. How is this different from RWS? One should argue that an open diff is better because it allows you to better feel the inside wheel start to spin up without a more sudden loss of traction typical with a locking diff. A locking diff is "artificially" directing power to the outside wheel the same way RWS is altering the effective wheel base of the car is it not?

stout

^ Great point. Was thinking along similar lines with PTV, but your example is purer.

What makes a mechanical LSD from a computer-controlled system different from RWS or PTV is repeatability. The driver learns what the mechanical item will do, as that's the only thing it can do if it is functioning correctly. Ditto for similar mechanical driver aids, such as toe correction, etc.

Systems like PTV or RWS introduce another "brain" to the equation, one that can make decisions on the fly in concert with other computers and systems and thus may not offer "perceptionally" similar repeatability, at least as far as the driver is concerned. Poor calibrations can make these systems seem distant and/or unpredictable to the driver�and some of BMW's electronic aids have been among the worst going all the way back to its early TC. Fortunately, Porsche's systems are usually VERY well calibrated, so as to feel "organic" and very predictable in use. The best ones hide themselves�you don't know they're at work...the car just feels great. Many PTV setups are that good, and I'd put RWS in there as well.

There are people who like both high-tech cars (991.2 Turbo, for instance), and people who pine for a modern 911 that follows the CGT method: less system, more materials technology with modern techniques. I like both. However, adding RWS to the T moves it more toward the 991.2 Turbo, which seems a bit outside the ethos that attracts me to the T. YMMV...

Loess

I definitely see what you are saying about the desire for a more simple car with less brains . But I think the RWS is a fairly repeatable system. I don't believe is adjusts for anything other than steering angle. If it tried to drive the car better than you (adjusting for yaw angle, traction control, temperatures) I think it would be much more intrusive. I do think that I've felt it strange on occasion in a corner when increasing speeds cross the point from turning in to neutral rear steering angle.

I'm curious why Porsche made it an option on this car. They didn't have to. I can only come up with they thought that the shortened wheel base feeling on tight twisty roads added to the overall feel of the car (or they just want more money). I would love to hear Jethro B's opinion of both after watching his 996 video.