Aerodynamic Drag / Speed Test (2.08)

[TimberW]

Do you know if the PP is being effected by the AERO now?

 

[Windfire1010]

Do you know if the PP is being effected by the AERO now?

Aero still effects pp, but not as much as before.

 

[Wardez]

The effect is looking substantial, good work guys. I have my own data to compare once I get home from work in a couple hours, hopefully someone else besides me recorded PP values for all levels of downforce as well.

 

[Windfire1010]

Weds Sport IS350 '08
2.07..min downforce 160.8
.max downforce 157.5

2.08 .min downforce 163.5
.max downforce 154.2

 

[marcus_war]

Calsonic Impul GT-R '08 2.07

• Minimum Downforce: 186.3 MPH
• Maximum Downforce: 184.3 MPH
• Unchanged Values: 185.2 MPH
• Total Difference: 2.0 MPH

Calsonic Impul GT-R '08 2.08

• Minimum Downforce: 189.3 MPH (+3.0 MPH)
• Maximum Downforce: 182.5 MPH (-1.8 MPH)
• Unchanged Values: 185.2 MPH
• Total Difference: 6.8 MPH

 

[bigbear]

I've updated seven cars in the OP so far.

Cars with non-customizable downforce, such as the McLaren F1, and cars with default aero settings don't seem to be affected at all by the update. For race cars the difference between maximum and minimum downforce speeds looks to be about triple what it was before.

I got an interesting result from the 458.

Ferrari 458 Italia '09 (w/ GT Auto Aero Kit)
Downforce/ v.2.07/ v.2.08/ Change
None......... 204.4... 204.4.... same
Min............ 204.3... 203.8....(-0.5)
Default....... 204.2... 201.8....(-2.4)
Max........... 204.1... 200.9....(-3.2)

PP values have changed a bit.

 

[Nicktune]

The effect is looking substantial, good work guys. I have my own data to compare once I get home from work in a couple hours, hopefully someone else besides me recorded PP values for all levels of downforce as well.

I did 👍
I haven't updated yet...I'll work on that another day...

 

[gordongt]

Looks like most of my database is now invalid Time to do it all again

EDIT: I'm currently doing tests now to alter my database and it seems to me that the only cars that seem to benefit from this are race cars or cars with down force already without buying it

 

[Smuttysy]

Gained just under 30mph top speed on my GTOne by removing the aero level from the rear, now running 334.5mph! My Redbull is now only running 340ish, seriously PD,,,, 800 extra horsepower seemingly doing nothing!

 

[Samus]

Gained just under 30mph top speed on my GTOne by removing the aero level from the rear, now running 334.5mph! My Redbull is now only running 340ish, seriously PD,,,, 800 extra horsepower seemingly doing nothing!

The GT One should not be going that fast.

 

[Exorcet]

The GT One should not be going that fast.

Yes, a 300 mph GT-One means something is wrong.

These initial results are definite improvements, but it seems like the effect varies car to car. The impact to the X1 and F1 seems good, but the Calsonic GT-R seems to only be very weakly affected. The Viper GTS-R and XJR-9 top speeds also vary less than I would have thought, but at the very least these might make a difference on high speed tracks.

Another interesting test to try might be to plot the top speed vs downforce curves for a couple of cars. It should be non linear with a greater change in top speed with high downforce values (example, Changing a rear wing from 70 to 60 should net a greater speed increase than going from 30 to 20).

 

[bs13]

My normal Nascar Indy setup which uses full downforce has lost 5mph on the straights. Went from 212mph to 207mph.

 

[phil_75]

Gained just under 30mph top speed on my GTOne by removing the aero level from the rear, now running 334.5mph! My Redbull is now only running 340ish, seriously PD,,,, 800 extra horsepower seemingly doing nothing!

Doesn't work like that. The X1 is built for track speed ie downforce not land speed record.

 

[Exorcet]

Doesn't work like that. The X1 is built for track speed ie downforce not land speed record.

Well, the X1 was designed to achieve downforce without high drag, and it does that in the low downforce setting. However since the X1 produces much more downforce than most other cars at max downforce, the drag is higher. The higher speeds also amplify the apparent effect of the drag.

 

[phil_75]

Well, the X1 was designed to achieve downforce without high drag, and it does that in the low downforce setting. However since the X1 produces much more downforce than most other cars at max downforce, the drag is higher. The higher speeds also amplify the apparent effect of the drag.

Thats a better explanation of what i meant:-)

 

[MOTORTRENDmitch]

Well, it is pretty cool that they have done a good job of this.. Real strategy is coming into play for Online rooms I believe.

 

[VBR]

I wonder if there's any difference between the online vs offline physics regarding the aero update?

 

[Windfire1010]

I wonder if there's any difference between the online vs offline physics regarding the aero update?

There is no difference between online and offline aero physics.

 

[bigbear]

I've updated all of the cars on page one.

Unfortunately the ACR's performance has not changed after the update. It still doesn't have customizable downforce so the result was expected.

Top Speed 2.07: 209.9
Top Speed 2.08: 209.9

Acceleration times are the same as well.

 

[acascianelli]

Gran Turismo Red Bull X2011 Prototype
Downforce/ v.2.07/ v.2.08/ Change
Min............ 316.0... 340.3....(+24.3)

...I wonder if 400mph is possible now.

 

[VBR]

There is no difference between online and offline aero physics.

Have you tested the same cars online/offline & came up with the same numbers to confirm this?

 

[bigbear]

Acceleration times don't tell much of a story but should affect lap times.

Minimum D.F. settings yield slightly faster times all 'round than before.
Maximum D.F. settings yield slightly slower times all 'round than before.

Chevrolet IMPALA (Stock Car) '11
MINIMUM D.F.
2.07:... 3.836(0-60)... 6.856(0-100)... 11.302(1/4)... 26.462(1M)
2.08:... 3.835(0-60)... 6.848(0-100)... 11.295(1/4)... 26.408(1M)

MAXIMUM D.F.
2.07:... 3.806(0-60)... 6.766(0-100)... 11.253(1/4)... 26.526(1M)
2.08:... 3.811(0-60)... 6.802(0-100)... 11.283(1/4)... 26.787(1M)

All of the cars I've tested so far show similar results. High dowforce still gives the car a faster launch and initial acceleration, and low downforce gives the car better speed on long straights.

Low downforce cars gain the advantage earlier now. They should be able to chase down high D.F. cars more effectively on long straights.


Front/Rear Downforce Ratios:
Before the update the Jaguar XJR-9 was fast with low downforce in front and high downforce in back.

high/low.... 60 front, 50 rear, 110 total, speed: 236.1
high/high... 60 front, 85 rear, 145 total, speed: 237.9
low/low....... 30 front, 50 rear, 80 total, speed: 241.7
low/high.... 30 front, 80 rear, 110 total, speed: 243.6 (fastest)

After the update this particular car was faster with low downforce both front and rear. Maximum downforce is now slower than high/low as well.

high/low.... 60 front, 50 rear, 110 total, speed: 239.4
high/high... 60 front, 85 rear, 145 total, speed: 236.5
low/low....... 30 front, 50 rear, 80 total, speed: 248.9 (fastest)
low/high.... 30 front, 80 rear, 110 total, speed: 247.6

Because downforce slows the car down more than before, you have to take more care when adding wing. This falls in line with the other speed tests. And, I think, is what people have been hoping for.

 

[daan]

Good work, bigbear 👍

I'm looking forward to trying this out. I've always been annoyed that you don't gain speed with less downforce in GT.

 

[Windfire1010]

Have you tested the same cars online/offline & came up with the same numbers to confirm this?

Yes I have test the same cars on and offline. The numbers were so similar that I say that they are the same.

 

[Lambob]

Hello,

which is faster?

a production street car with no aero wing,
or the same car, with a minimum set downlforce wing?

 

[dr_slump]

Hello,

which is faster?

a production street car with no aero wing,
or the same car, with a minimum set downlforce wing?

Usually the one with stock wing.

 

[BWX]

What about the aero bug where you jack up nose and drag tail end on ground on high downforce car and go 50mph faster(maybe more/less)?

 

[Niop]

What about the aero bug where you jack up nose and drag tail end on ground on high downforce car and go 50mph faster(maybe more/less)?

That ride height still makes the car faster, but adding Aero on the rear slows the car down.

 

[BWX]

That ride height still makes the car faster, but adding Aero on the rear slows the car down.

As before more rear aero would make it faster with that crazy settup you mean? (I hope)

I've only experimented with that setup once pre 2.08.. but I got my 787B going faster than 99% of the people on GTP at the time. Can't remember how fast, but it wouldn't steer, and sparks out back, but was flying.

 

[Niop]

As before more rear aero would make it faster with that crazy settup you mean? (I hope)

I've only experimented with that setup once pre 2.08.. but I got my 787B going faster than 99% of the people on GTP at the time. Can't remember how fast, but it wouldn't steer, and sparks out back, but was flying.

Yep, correct.