991 RS ON TRACK

[LaSource]

APOLO1 said:

respectfully I disagree, I know the diff between lateral grip, tyre contact and aero.....had a good chat with some WEC drivers at Silverstone and Goodwood, car drives exactly as they said it would,...It has about same amount of DF as the 918,(918 is active)and about 700lb less weight...

Don't think we are disagreeing. Not questioning your experience. I'm sure it drives just as the WEC drivers expect it to.

I was commenting on RDMcG's comparison of three generations of RS on their launch tyres in heavy rain. There is almost night and day difference in the water draining capabilities of cup 1 and cup 2 which will heavily influence the resulting pperformance of the car.

[hunter 66]

In GT3 ( Race cars ) the aero improvements in the last few years have been impressive especially in the wet ...

[hornbaek]

I had a go at Goodwood a couple of weeks ago and the GT3 RS is very very quick around the circuit. Without too much effort i was very close to the lap record for street legal cars at Goodwood. The aero makes all the difference as you can carry ridiculous amounts of speed into the fast corners without the front end becoming light. Noise put a limit to how fast I could go as I passed the noise limit at 101.5 db for "drive through" and was subsequently black flagged before slowing down a bit. Already the 997 4.0 gives you more front end grip with the winglets and the increased camber but the 991 is in a different league altogether.

Edited by hornbaek on Saturday 10th October 11:16

[isaldiri]

hunter 66 said:

In GT3 ( Race cars ) the aero improvements in the last few years have been impressive especially in the wet ...

Downforce is proportional to the square of speed and cars are running slower in the wet plus with softer suspension. No doubt the aero improvements in the race cars have been significant but especially so in the wet...?

[APOLO1]

hornbaek said:

I had a go at Goodwood a couple of weeks ago and the GT3 RS is very very quick around the circuit. Without too much effort i was very close to the lap record for street legal cars at Goodwood. The aero makes all the difference as you can carry ridiculous amounts of speed into the fast corners without the front end becoming light. Noise put a limit to how fast I could go as I passed the noise limit at 101.5 db for "drive through" and was subsequently black flagged before slowing down a bit. Already the 997 4.0 gives you more front end grip with the winglets and the increased camber but the 991 is in a different league altogether.

Edited by hornbaek on Saturday 10th October 11:16

I hold a lap record for a Production car in my 918 on a UK track, faster than R500 Duratec on Avon ZRs...

Genuinley feel that the RS will be faster...

The only car I have experienced that imv will stay with, or get close to the RS on track is the Mac 675LT

[TrackTwit]

APOLO1 said:

I hold a lap record for a Production car in my 918 on a UK track, faster than R500 Duratec on Avon ZRs...

Genuinley feel that the RS will be faster...

The only car I have experienced that imv will stay with, or get close to the RS on track is the Mac 675LT

What about the Turbo S? Same lap time on Anglesey as the RS!!

[hunter 66]

Agree but due to the low grip in the wet it plays a greater role .......... just the feeling driving them

[Mark A S]

hornbaek said:

I had a go at Goodwood a couple of weeks ago and the GT3 RS is very very quick around the circuit. Without too much effort i was very close to the lap record for street legal cars at Goodwood. The aero makes all the difference as you can carry ridiculous amounts of speed into the fast corners without the front end becoming light. Noise put a limit to how fast I could go as I passed the noise limit at 101.5 db for "drive through" and was subsequently black flagged before slowing down a bit. Already the 997 4.0 gives you more front end grip with the winglets and the increased camber but the 991 is in a different league altogether.

Edited by hornbaek on Saturday 10th October 11:16

What flying lap time did you do ?

[andrew]

michael243 said:

Why is the number plate covered for the track?

either to potentially deceive the car's next owner or the insurance company

[michael243]

Steve Rance said:

Because it protects the anonymity of the car if he is unfortunate enough to have an off.

To hide the fact it was that car that crashed...?

The time I went to a track day, none of the cars had the plates covered...

[isaldiri]

Preventing overly nosey people from recording various details of one's car seems as good a reason as any to cover one's numberplates imo.

[Steve Rance]

hunter 66 said:

Agree but due to the low grip in the wet it plays a greater role .......... just the feeling driving them

srill need a set of wets though my dear old thing., Ithe only aero that's useful in the wet is a parachute

[Magic919]

Given it's the same plate from his black GT3 and you can read some of it through the tape, it's a moot point.

[hunter 66]

Steve ,,, So you never adjusted your wing in the wet for more downforce no wonder you always fell off....haha ....... just kiding but it would be strange if your were doing a wet race and you took the downforce away by having less wing ........
Even Porsche says the big factor is downforce improvements ......... are the slats over the front wheels just for looks ...
The change in GT3 aero from 2010 to 2014 was huge and cars are 6 secs a lap faster at Silverstone ...

Edited by hunter 66 on Tuesday 13th October 10:55

[Steve Rance]

Ha! I love the wet. Great equaliser. My wet set up priority a are:
1. Tyre choice
2. Anti roll bar settings
3. Brake bias set up
4. Damper settings
5. Ratio choice - if applic
6. Aero

The big gainers in GT3 have been power, tyres and transmissions. Aero plays a part but it's not up there with the former. Obviously it is a factor in FIA GT3 but more so in Prototype and single seat catagories. But on a relatively heavy road car on road tyres?

[APOLO1]

isaldiri said:

Preventing overly nosey people from recording various details of one's car seems as good a reason as any to cover one's numberplates imo.

Actually, never did this before....
Just did know what to expect 1st time out on track, even more so in the very wet condition's,. Car was and is faultless....

[hunter 66]

Hi Steve yes this is the point I was trying to make that for the first time aero is being used effectively on a road Porsche to this level ... as for GT3 race cars the big change is not Power ( restricted ) not tyres same as many years , not gearboxes ( ditto ) but aero . So they are more like prototype/single seaters .
Anyway irrelevant , but car looks great and have seen on board at the Ring , drives well ..........maybe when we are older we can blag a drive from a friend

[APOLO1]

[quote=APOLO1]

Actually, never did this before....
Just did not know what to expect 1st time out on track, even more so in the very wet condition's,. Car was and is faultless....

[fioran0]

It always irks me when Porsche sell with numbers without quantifying them. Downforce is one of the big ones they enjoy doing it on but its not the only one.
I find it interesting that they don't stand behind the actual number, instead choosing to discuss it relative to some other unspecified reference point. But perhaps thats just me.... I am not their target demographic with this info after all.

The downforce "gains" on the new 991 GT3 and RS are interesting. The base GT3 gained a lot of downforce up front in terms of balance when looking at the actual numbers produced in the wind tunnel.. This shift in balance appears to remain with the new RS too. I could speculate why but will leave it for now.

I made a quick graph using actual data from shock pots on a 997.1 Cup and actual data points for the 991 GT3 and RS.
I blanked out the raw data points from the Cup along with axis info since this is my own data and I don't want to post the hard numbers. I am aware of the apparent irony of this move given my opening sentences. No need to point it out.
It is worth keeping in mind the different weights on each car too when looking at the below. The Cup is obviously the lightest car of the three.

|http://thumbsnap.com/MALHy6Ey[/url]

Thanks to Isaldiri for the updated data points for the RS. Graph changed from 300% figure to measured and reuploaded.

Edited by fioran0 on Tuesday 13th October 18:38

[isaldiri]

fioran0 said:

It always irks me when Porsche sell with numbers without quantifying them. Downforce is one of the big ones they enjoy doing it on but its not the only one.
I find it interesting that they don't stand behind the actual number, instead choosing to discuss it relative to some other unspecified reference point. But perhaps thats just me.... I am not their target demographic with this info after all.

The downforce "gains" on the new 991 GT3 and RS are interesting. The base GT3 gained a lot of downforce up front in terms of balance when looking at the actual numbers produced in the wind tunnel. I sadly haven't seen any hard data for the RS so can only guess as to what it is producing based on the 300% figure thrown around by the master salesman from the mothership. This shift in balance therefore appears to remain with the new RS too. I could speculate why but will leave it for now.

In case you hadn't seen this one, I've swiped it off rennlist as I guess you might find it interesting



Porsche AFAIK did stand behind a hard number for the RS at 330kg or so kg of downforce at 300km/h for the RS.

I was told by someone previously that based on those numbers the RS is a lot more balanced aero wise than the 991 gt3 as ideal front/rear downforce balance is supposed to be more or less weight distribution biased (with a slight rear bias on top of that).. not sure if that is true though but he did seem to know what he was talking about!