Tuning Garage Links & FITT Physics Discussions

Did some testing tonight. Tried to approach things methodically, scientific. I took the MX-5 Miata '89 to Willow Springs Street Course on comfort soft tires. There is a nice little skid pad to the left, just after the free run begins.

Here is what I learned... nothing. Not a damn thing. Super frustrated with improving tuning over the stock settings. With stock settings I could only run around the white line of the skid pad at 41 mph. The outside front turned red and the inside front turned yellow.

Front Camber:
Tested 1.0, 2.0, 3.0, 2.5, 2.2
41 mph across the board. Though the speed was identical in each test, at 2.2 it was the easiest to hold the line. In reality there was so little difference in speed.

Rear Camber:
Tested 1.0, 2.0, 3.0, 4.0, 6.0
41 mph across the board. Identical speed result, but the inside rear began to turn yellow at 4.0 and almost turned red at 6.0. Again, very little difference in speed.

Rear toe from 0.20 to 0.00. Absolutely zero difference.

Added LSD from stock 0/0/0 to 8/14/7. Zero difference.

Ride height from 140/140 to slammed 75/75. This is the only setting where I could feel any difference. I went from fluttering between 40/41 mph to flutter between 41/42. Still, not very much improvement in my mind.

Kept her slammed and increased spring rates. Tested both half way across the slider and 3.4 across the slider. Zero difference.

Dampers from 1's up to compression at 6/6 and extension at 5/5. No change.

Then I decided to go crazy. I put settings to full soft front and full hard rear.
RH 75/160
SR 2.89/10.58
Dam Ex 1/10
Dam C 1/10
ARB 1/7
Cam 2.0/0.0
Speed did not increase one bit. Car rotation did not improve. The only difference is that the inside rear wheel could now turn red and the outside rear turned yellow. If I kept going, I could get both rear tires to break loose, but the car still would not rotate.

So tonight's conclusions. Mazda has paid PD enough to program Miata to handle perfectly and never spin out. What a waste of a night of tuning. I think I may need to test at higher speeds. Maybe try this same type of effort on Twin Ring Motegi Super Speedway?

I agree with everything here. I was playing around with the Clio RS 11 the other night and couldn't really get much out of it. One thing I did find is that it appears that Ride Height is backwards. I got the car to rotate more by max raise the front and slam the rear. I didn't try it with any other car. Maybe try it with the Miata and see what you think. I thought that the spring rates may be as well to, but I didn't get the chance to really mess with them.

I am going to try it with my VW GTI tonight to and see what I find.
 
The differentials is very touchy under power. The power is delivered through it is different from car to car a lot different. I'm find on turbo cars the power comes on strong very strong and NA cars have a smoother output. Getting it to hook to the track is a lot easier too.
 
Hi all, I'm new to GT having switched over from Forza 4 (I don't even have the game yet). I'm following this thread in interest as I love a bit of tuning science.

I'm especially interested in ways to tune camber. In Forza you have detailed tyre temperature telemetry which makes it a simple task.

Hopefully my PS3 will turn up soon and I'll be able to contribute!
 
I'm especially interested in ways to tune camber. In Forza you have detailed tyre temperature telemetry which makes it a simple task.

That is the way we do it in the real world. Tire tems on the outside, middle and inside of the contact patch. Inside and middle temps should be close to the same and outside temps a little cooler. For "The Real Driving Simulator" you would think that could be added to the tuning section of the game. Instead, it is a whole lot of guessing.
 
Flat Floors?

Bought a Civic Type R (EK) '97 for the National A one make race. Installed Sports Hard tires Racing Hard Suspension, Sports Computer, Sports Exhaust and Catytic Converter: Sports.
Decided for S&Gs to install the flat floor.
Then I set the Power Limiter to 97.5 which gave me 200HP and 225PP.
Ran the race a few times then decided to see how much difference the Flat Floor was making so paid to remove it.
No other changes but now was at 406PP.
Ran the race several more times and my average lap times were about a second quicker without the Flat Floor.:odd:
Thought maybe I had just started to get in the groove so put the Flat Floor back on but again times were about a second slower.:(
Is the Flat Floor actually creating drag and slowing the car down like having high Aero will or is this just a case of my bad driving and slight variations in AI field?
 
^^ Did your car have any rake? In theory, you'd get more downforce with lower front than rear and some lift with higher front. Flat floors should aid ground effect and exaggerate the aero effect (although it's probably more complex than that).

But.. ride height seems to be reversed so you might be getting the opposite of the desired effect.

I'll try to test this out next time I'm on the PS3.
 
Flat Floors?

Bought a Civic Type R (EK) '97 for the National A one make race. Installed Sports Hard tires Racing Hard Suspension, Sports Computer, Sports Exhaust and Catytic Converter: Sports.
Decided for S&Gs to install the flat floor.
Then I set the Power Limiter to 97.5 which gave me 200HP and 225PP.
Ran the race a few times then decided to see how much difference the Flat Floor was making so paid to remove it.
No other changes but now was at 406PP.
Ran the race several more times and my average lap times were about a second quicker without the Flat Floor.:odd:
Thought maybe I had just started to get in the groove so put the Flat Floor back on but again times were about a second slower.:(
Is the Flat Floor actually creating drag and slowing the car down like having high Aero will or is this just a case of my bad driving and slight variations in AI field?

Flat floor adds a RIDICULOUS amount of drag. Also seems to add a pretty fair amount of downforce, but the drag is seriously nasty. Found this out the hard way, had a GT500 I built for Like The Wind, got the power mods done, won a few, decided to see what the flat floor would do... Instantly lost a good 15mph of top speed. Still won because it was still pure evil in the draft, but it was quite eye opening.

As for rake, in my testing it doesn't seem to be worth terribly much as far as raw grip goes. Also found that rear ride height has a much larger impact on top speed than front ride height (used SSRX test mode, ran WOT to 10k with various suspension settings, fastest was actually fully slammed instead of nose up, tail down like it used to be, however slamming the rear had a MUCH more pronounced effect than doing so to the front).

I've also found that roll rates need to be fairly thoroughly balanced to get a car to handle. Too stiff up front and you get general understeer, too soft and the nose will wash out worse when driving hard. Need to start testing some rear-engined cars just to see how it works but I'm unfortunately too tired after work to even consider it.
 
Anyone else have Sports: Soft tires grip better than Racing: Hard/ Medium? I was working on the '07 GT-R earlier with SS tires and got to a point where I was happy with the car. I decided to put some RM tires on and didn't even get to start a lap of the Nurb because I went off track.
 
Anyone else have Sports: Soft tires grip better than Racing: Hard/ Medium? I was working on the '07 GT-R earlier with SS tires and got to a point where I was happy with the car. I decided to put some RM tires on and didn't even get to start a lap of the Nurb because I went off track.
I’ve found that the tires are taking a long time to warm up due to the tire angle and toe, after a lap and half the tire will start to come in.
 
Flat floor adds a RIDICULOUS amount of drag. Also seems to add a pretty fair amount of downforce, but the drag is seriously nasty. Found this out the hard way, had a GT500 I built for Like The Wind, got the power mods done, won a few, decided to see what the flat floor would do... Instantly lost a good 15mph of top speed. Still won because it was still pure evil in the draft, but it was quite eye opening.
So do you guys think the drag effect is over powering the increased down force in a standard lower speed circuit track? I was racing yesterday against the same car at bathurst. And in almost every straight i was getting out accelerated by the exact same s2000. Now I'm wondering if he didn't have flat floors. I also haven't tuned the tranny but the acceleration difference seemed significant.
 
Anyone else have Sports: Soft tires grip better than Racing: Hard/ Medium? I was working on the '07 GT-R earlier with SS tires and got to a point where I was happy with the car. I decided to put some RM tires on and didn't even get to start a lap of the Nurb because I went off track.
I’ve found that the tires are taking a long time to warm up due to the tire angle and toe, after a lap and half the tire will start to come in.
I'm almost sure that there is a problem with front racing tires grip level.
Any car well balanced under sport tires, sliding the 4corners the same amount when pass the grip, will loose this fine balance when you wear it Racing tires. To find again the same driving feeling of a good car well balanced you need to add one more point of grip at the rear or less one point of grip at the front.

For example a car OK with any kind of sport tires, will go well under racing tires if you wear :
front SS rear RH or RH / RM or RM / RS.

To resume, it seems to me that PD add 1 point of grip to the front racing tires only... Is it possible ??? I don't know, but do yourself the experience and you will see this exactly.


Very strange.
 
So do you guys think the drag effect is over powering the increased down force in a standard lower speed circuit track? I was racing yesterday against the same car at bathurst. And in almost every straight i was getting out accelerated by the exact same s2000. Now I'm wondering if he didn't have flat floors. I also haven't tuned the tranny but the acceleration difference seemed significant.

Same here, bathrust 550pp sh.
Two NSXs, one with flat floor reach 396hp while another one without it reach 460hp

On the straight section, it was a massacre for flat floored car but in the mountains, just like a walk in the park.
Without flat floor, laptime 2:13 highs
With flat floor, laptime 2:15.. could be in 2:14 but must be in suicidal mode, lol
 
The only time I've have trouble with the front tires losing grip @praiano63 was from either overload, too high of a camber angle, or overheating. Track temperature is also playing a big part to the way the tires grip. I’ve been refining the set I have for the BMW Z4 GT3 race car for Brands Hatch, running testing during different times on the track testing for about 2 hours gathering info and I’ve found that the track really start to get slick during mid-day, the tires fall off to when they get over heated. The area I’m having trouble in now if getting the car to rotate correctly.
 
Ok so I did some testing today on Flat floors after reading Rotary Junkie's post. My testing involved Deep Forest, 450pp s2000, and SH tires. I first did a shake down and got a mild tune done to the car with out flat floors. I managed a 124.5 ish time. I'm pretty consistent on this track and clocked multiple 124s. I then installed the flat floors and saw a huge PP change. I'm sorry I forgot to note the exact amount but I believe it was around 20PP. Without changing any setting other than adjusting HP for the PP change I managed a 125.6 best time. I noticed with the flat floors it really helped the car turn in better. Actually the whole car was much more predictable, but I also noticed a huge downgrade in acceleration. The higher cornering speeds just weren't making up for the loss in straight line power. Granted with the flat floors I might be able to tune it better and achieve slightly higher cornering speeds, but I still think the acceleration took too big of a hit. Then I took the flat floors off and on my second lap did a low 124.

So I think it would be interesting to see others findings on this as well. I could see how having flat floors might give an advantage at maybe short tracks, but I'm not sure. It definitely enhanced the handling with the increased down force, but I still think it might be doing more harm than good.
 
Find it odd that PD has given Flat Floors such a huge impact on PP while actual Aero Downforce settings have zero impact on PP.
The Evo IX Touring Car I've been playing with most of the day has exact same PP whether the aero is 50/50 or 150/350.
 
Yes flat floors take away 20pp when added. Thats close to 60hp. Now if you race in a room where its HP and weight flat floors would be excelent. But in pp racing it would hurt in almost all cases unless you find a turd that has a huge HP advantage at a certain pp.. but some cars you cant add it to..
 
Added three garages to the list in post #5.
AVRG
SEGA
HaB

Should this thread get a sticky?

I also want to start linking the good conversations about tuning. Please make thread recommendations to me and I will link. Hoping that this thread can be a starting point for finding tuning advice.
 
The flat floor are adding a aerodynamic number to the PP and more than 20, I put a flat floor on a Boss 302 and it gained 27PP points. Everything besides the areo parts and window weight reduction is adding PP to all the cars. Has anyone else done any tuning without lowering the power limiter? The reason why I ask is because I see some of the same tuning classes being worked on from GT5.
 
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Should this thread get a sticky?

I also want to start linking the good conversations about tuning. Please make thread recommendations to me and I will link. Hoping that this thread can be a starting point for finding tuning advice.

Yes, it should.

And I will keep my eyes pealed for random, but worthy, tuning information.
 
Hello FITT people and Co.
I don't have a lot of time to make test because i just can't stop driving and tuning....:lol:

But, i did a strange discovery over brakes. Here is my experience and first the procedure.

1-Take any car, road, racing, with downforce or not, fast ,slow, heavy , light........... the way you want.

2- Go to test drive at stage route X

3- Start normally and let the car hit the limiter in 2cd gear. This will allow to modulate a equal speed for all test to come .

4- When you pass the starting line ,shift in 3rd gear , always full gas, and grow more speed till the 2000 meters shifting at read zone limit.

5-Then when you pass under the 2000 m gate exactly on the line, brake everything you can, full brakes, downshifting till the car stop.

6-Now, just count the white strips of the track , till the next yellow mark , to know exactly the braking distance.

Repeat everytime the same procedure. Easy.

My results with all the cars i've tested.

For Brake balance 0/0 - 10/10 - 0/10 - 10/0 the braking distance is exactly the same.

More than this, If you instal the racing brakes kit , you still have the same braking distance.

My conclusions:

1- Increasing the number don't increase the braking potential.

2-The brake balance is not more or less brake in front or at the rear. It just act together with the course of the braking pedal. If you have a BB 0/10 for example and if you brake progressively, the braking force will come first at the rear at the beginning of the course and after at the front when full course of the pedal. The tendency at this moment is to generate oversteer during the time you'll press the pedal, with more or less inertia depending of your foot pressure.

3- Specially with racing tires, because more grip you have, more the effect is strong, i'll use a low BB like 2/0, like this the car don't upset when braking in a curve and you gain a better driving line control.


One more thing about racing tires and the way they take the grip.
I think PD increase the % of grip over the red & white stripes out corners and inside apex. Perhaps they did this to make safer some out corners when you reach the limits of the track.... It seems a bit more grippy yes at this moment.
It could be a good idea, but the problem is inside the corner ,when you reach the apex with your racing tires, and if you pass over the red & white strip, it will cause an excess of grip on the front interior tire, that will make you oversteer very strongly or even spin.

OK, That's all folks. I hope i was clear enough wit my bad english.
Have a good night everybody.
 
Hello FITT people and Co.
I don't have a lot of time to make test because i just can't stop driving and tuning....:lol:

But, i did a strange discovery over brakes. Here is my experience and first the procedure.

1-Take any car, road, racing, with downforce or not, fast ,slow, heavy , light........... the way you want.

2- Go to test drive at stage route X

3- Start normally and let the car hit the limiter in 2cd gear. This will allow to modulate a equal speed for all test to come .

4- When you pass the starting line ,shift in 3rd gear , always full gas, and grow more speed till the 2000 meters shifting at read zone limit.

5-Then when you pass under the 2000 m gate exactly on the line, brake everything you can, full brakes, downshifting till the car stop.

6-Now, just count the white strips of the track , till the next yellow mark , to know exactly the braking distance.

Repeat everytime the same procedure. Easy.

My results with all the cars i've tested.

For Brake balance 0/0 - 10/10 - 0/10 - 10/0 the braking distance is exactly the same.

More than this, If you instal the racing brakes kit , you still have the same braking distance.

My conclusions:

1- Increasing the number don't increase the braking potential.

2-The brake balance is not more or less brake in front or at the rear. It just act together with the course of the braking pedal. If you have a BB 0/10 for example and if you brake progressively, the braking force will come first at the rear at the beginning of the course and after at the front when full course of the pedal. The tendency at this moment is to generate oversteer during the time you'll press the pedal, with more or less inertia depending of your foot pressure.

3- Specially with racing tires, because more grip you have, more the effect is strong, i'll use a low BB like 2/0, like this the car don't upset when braking in a curve and you gain a better driving line control.


One more thing about racing tires and the way they take the grip.
I think PD increase the % of grip over the red & white stripes out corners and inside apex. Perhaps they did this to make safer some out corners when you reach the limits of the track.... It seems a bit more grippy yes at this moment.
It could be a good idea, but the problem is inside the corner ,when you reach the apex with your racing tires, and if you pass over the red & white strip, it will cause an excess of grip on the front interior tire, that will make you oversteer very strongly or even spin.

OK, That's all folks. I hope i was clear enough wit my bad english.
Have a good night everybody.
I'm not sure I understand your second conclusion *about brake balance.
You mention the course of the brake pedal which I'm guessing you mean the travel of the pedal, right? Is the bias the same throughout light to heavy brake pressure? Or does it change?
Your example of 0/10 BB, saying it starts at the rear then ends in the front. That's where I'm confused.
-Thanks Praiano
 
I'm not sure I understand your second conclusion *about brake balance.
You mention the course of the brake pedal which I'm guessing you mean the travel of the pedal, right? Is the bias the same throughout light to heavy brake pressure? Or does it change?
Your example of 0/10 BB, saying it starts at the rear then ends in the front. That's where I'm confused.
-Thanks Praiano
Yes, travel of the pedal...:ouch: .
For example with 0/10 the rear brake will be ON since the first part of the pedal travel. At the end of the travel the front brake will begin to be effective.
Depending of the pressure and the speed your foot smash the brake pedal ,the reaction of your car during a turn under brake will be brutal or smooth.
Hard for me to explain with my english. Do the test and make a better text. Sorry for this.
 
Yes, travel of the pedal...:ouch: .
For example with 0/10 the rear brake will be ON since the first part of the pedal travel. At the end of the travel the front brake will begin to be effective.
Depending of the pressure and the speed your foot smash the brake pedal ,the reaction of your car during a turn under brake will be brutal or smooth.
Hard for me to explain with my english. Do the test and make a better text. Sorry for this.
Thanks brother! Much respect to you. English is a bit of an over achiever. Too much fluff :-) I'll see what I can do to help clear this up.
 
I confirm the problem of the white & red stripes inside the turns. They really have more grip than the asphalt and induce oversteer when the inside front racing tire pass over it.
I did the test at this spanish track that i don't remember the name??? in the open country!! It don't have red & white paint but a small white paint that have the same grip as the asphalt. Everything OK when you pass over , no change of grip disturb your line.
 
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