Consolidated 991RS thread
03-05-2015, 04:48 PM
#6391
Intermediate
Join Date: Feb 2015
Location: Germany
Posts: 48
Likes: 0
Received 0 Likes
on
0 Posts
I asked that question already before but does anybody know how the dashboard would look like if I do not chose that leather option? Would it be plastic or Alcantara? u know I mean the dashboard from above where the stop watch would be etc. Thansk
03-05-2015, 04:58 PM
#6393
Rennlist Member
Join Date: May 2012
Location: Mid-Atlantic (on land, not in the middle of the ocean)
Posts: 12,880
Received 4,228 Likes
on
2,412 Posts
03-05-2015, 04:59 PM
#6394
Rennlist Member
I'm actually debating the idea of using a Crawford wing on my GT3, (just on the track), I'd put my old wing back the GT3 for the rest of my driving.
Last edited by Drifting; 03-05-2015 at 05:07 PM. Reason: .
03-05-2015, 05:06 PM
#6395
Banned
Join Date: Jul 2013
Posts: 440
Likes: 0
Received 0 Likes
on
0 Posts
"In 1-4 the GT3 should be quicker, in the lower rpm range the RS quicker in the upper rpm range, no surprise as the torque is similar down low w/ the RS excelling up high and weight of GT3 is not much more and aero hasn't become a huge factor"
This is what he said. Maybe it's the way it's written as it's not very easy to read.
This is what he said. Maybe it's the way it's written as it's not very easy to read.
03-05-2015, 05:12 PM
#6396
Rennlist Member
Join Date: May 2012
Location: Mid-Atlantic (on land, not in the middle of the ocean)
Posts: 12,880
Received 4,228 Likes
on
2,412 Posts
"In 1-4 the GT3 should be quicker, in the lower rpm range the RS quicker in the upper rpm range, no surprise as the torque is similar down low w/ the RS excelling up high and weight of GT3 is not much more and aero hasn't become a huge factor"
This is what he said. Maybe it's the way it's written as it's not very easy to read.
This is what he said. Maybe it's the way it's written as it's not very easy to read.
03-05-2015, 05:14 PM
#6397
Nordschleife Master
03-05-2015, 05:16 PM
#6398
Rennlist Member
Join Date: Feb 2006
Location: Wishing I Was At The Track
Posts: 13,588
Received 1,824 Likes
on
948 Posts
Short live show video embedded here:
http://www.autoblog.com/2015/03/03/2...o-geneva-2015/
And photo of orange stripe on steering wheel for orange interior:
http://www.autoblog.com/2015/03/03/2...o-geneva-2015/
And photo of orange stripe on steering wheel for orange interior:
03-05-2015, 05:20 PM
#6399
Downforce goes to the square of speed. Porsche's figures are quoted at 300 kph, so if you cut speed in half you'll (.5 x .5 = .25) cut downforce to 1/4. So 80 kg or 175 lbs of downforce at 150 kph/ 93 mph.
If the car weighs 3250 lbs with light fuel and driver this represents about 5.4% of the car's weight, so you'd see a bit over a 5% increase in cornering grip, or closer to 6% when you account for the fact that you can go faster through the corner and hence create even more downforce. Net you'll take the "93 mph" corner a bit over 2.5 mph faster than if you didn't have downforce.
Go faster and things get more interesting: In a 124 mph corner downforce is contributing 312 lbs (near 10%), letting you take the corner faster which raises downforce further. You end up being able to take the "124 mph corner" at over 130, a very substantial speed difference to be carrying down the straight.
Downforce going to the square is a slight oversimplification- in reality things like ride height and pitch changes, flow separation, etc meant that it's not quite correct, but it's usually very close.
If the car weighs 3250 lbs with light fuel and driver this represents about 5.4% of the car's weight, so you'd see a bit over a 5% increase in cornering grip, or closer to 6% when you account for the fact that you can go faster through the corner and hence create even more downforce. Net you'll take the "93 mph" corner a bit over 2.5 mph faster than if you didn't have downforce.
Go faster and things get more interesting: In a 124 mph corner downforce is contributing 312 lbs (near 10%), letting you take the corner faster which raises downforce further. You end up being able to take the "124 mph corner" at over 130, a very substantial speed difference to be carrying down the straight.
Downforce going to the square is a slight oversimplification- in reality things like ride height and pitch changes, flow separation, etc meant that it's not quite correct, but it's usually very close.
03-05-2015, 05:27 PM
#6400
Front downforce is the limiting factor- it's always easy to add too much rear downforce with a wing. I suspect a deeper splitter and canards might let you get to around half of the GT3 RS's front downforce, meaning you'll be limited on rear wing angle by understeer. I don't believe you'll get to 85% with good balance without more extensive changes.
03-05-2015, 05:41 PM
#6401
Addict
Rennlist Member
Rennlist Member
Bill - there is something amiss with your gear chart. The gearing difference between the GT3 and RS is less than 1% when compensating for R&P and tires (RS net taller by 0.9%). Your speeds for the RS are much more than 1% more than the GT3 and the RS has a lower redline...
Speed in gear should be a little lower for the RS, rather than ~20% higher.
Speed in gear should be a little lower for the RS, rather than ~20% higher.
Last edited by GrantG; 03-05-2015 at 06:01 PM.
03-05-2015, 05:44 PM
#6402
Rennlist Member
Yeah, I gotta say, I'm saddened by the extremely limited customization options available on the GT3 RS. 
No Extended Leather. No Deviated Stitching (other than the silver or orange ones that are forced).
(And, of course, no PTS -- yet.)
No Extended Leather. No Deviated Stitching (other than the silver or orange ones that are forced).
(And, of course, no PTS -- yet.)
03-05-2015, 05:44 PM
#6403
Rennlist Member
Canards don't contribute much, normally in the range of a 10%+ increase in front downforce.
Front downforce is the limiting factor- it's always easy to add too much rear downforce with a wing. I suspect a deeper splitter and canards might let you get to around half of the GT3 RS's front downforce, meaning you'll be limited on rear wing angle by understeer. I don't believe you'll get to 85% with good balance without more extensive changes.
Front downforce is the limiting factor- it's always easy to add too much rear downforce with a wing. I suspect a deeper splitter and canards might let you get to around half of the GT3 RS's front downforce, meaning you'll be limited on rear wing angle by understeer. I don't believe you'll get to 85% with good balance without more extensive changes.
However the down-force rating % is more on the front of GT3 than Gt3RS currently right? So perhaps you have a bot more room to play with that 10% extra front transfer? I guess the best way to find out is to play with it. I think Spartan and MilehighMike? are experimenting with this for us. I have no doubt they will not reach GT3RS levels of downforce as the hips are not as wide or flat on top and there arent the slashes in the front fenders nor the width up there etc. Its really interesting to get a grip on this aero thing - till 991 GT3RS I really paid little attention!
03-05-2015, 06:01 PM
#6405
Nope
cwp 3.973 on GT3 & 4.188 on the GT3RS the ss rounds those cells in the view but not in the calcs
tires are
Michelin Sport Cup 2s
GT3 305/30x20 OD27" w/ a dynamic rolling height of 26.2"
RS 325/30x21 OD 28.7 w/ a dynamic rolling height of 27.9"
cwp 3.973 on GT3 & 4.188 on the GT3RS the ss rounds those cells in the view but not in the calcs
tires are
Michelin Sport Cup 2s
GT3 305/30x20 OD27" w/ a dynamic rolling height of 26.2"
RS 325/30x21 OD 28.7 w/ a dynamic rolling height of 27.9"
Last edited by Bill Verburg; 03-05-2015 at 06:29 PM. Reason: error correction