How to set your gearbox in GT6
I’ll try to stay as clear as possible.
This method fit to most of the cars in GT6.
The goal is to spread the gears at the best place ,where the max power is.
I’ll consider also that the car need to perform a good standing start, classic situation in an online race.
I’m going to take the Nurb Nordschleife for example with my:
BMW M3 CSL // 550PP // SPORT MEDIUM 499 HP at 8700 RPM
Nordschleife is the place where a good launch is very important.
So ,you have a car with a given power ,with a certain kind of tires.
The first thing to do is go back at the beginning of the straight , 4 km back, to check the top speed you need.
To this speed you’ll have to add 10 kmh in case of draft but in this case you'll see that there is some room till red zone.
How to set the max speed if the GT6 setting panel don’t show this top speed ??
Go on track to check it.
After the test you saw that you reach 320 kmh.
Back to our “ring” gearbox.
We will talk about % on the setting bar.
1- Move your final gear to the right , around 75% of the setting bar in this case 4.000.
2- Set the top speed slider to the minimum value, lower top speed available ,here 200 KMH.
3-Set the last gear ratio full right on the setting bar = 100%
4-Move again your final gear to an aproximative low value, between 0% and 20% is ok. Here we need 2.050 to reach the 320 KMH at 8700 RPM +-
Now check your top speed on the straight or enter the value on the excel sheet to see if your top speed is OK. Here just after the bridge end of straight.
OK, now you have set the last gear we have a 6th gear ratio at 100%, full right on the panel, and your final gear to reach the speed you need on this track.
For the other gears it’s very simple.
You need to perform a good standing start to jump in front of the race.
Go on track again, check your start.
-Wheels must not spin too much , you loose grip like this and stay behind.
-The car must not squat too ,falling engine RPM loosing power and staying planted on the starting line.
To set the perfect launch after test it, you set your 1st gear to 40% of the setting bar (39% exactly in this case 4.550).
The only thing you need to do now is to spread visually the 2,3,4,5th gears between the 1st and last 6th.
It will give:
1st = 40%
2d = 55%
3rd = 70%
4th = 85%
5th = 90%
6th = 100%
To do this visually is not easy because PD take out the graduations on the setting bar that we had in GT5.
So,to be exact in your ratios calculation, you can use our excel sheet to calculate it. My friend Sam did a good job ,just play with it together with your setting panel to enter the datas and you’ll understand it in a few minutes of practice.
Here is the link to google doc sheet. You can download ,clic "file" and "download as excel file"
I don't know how many time it will stay OK because anybody who have access can edit it. Or send me a mail and i send you back the original.
GT6 gearbox calculation sheet
Just follow the tips, enter the red value only.
To calculate by approximation the tires perimeter ,go on route 10 and check your exact speed in any gear at a given RPM.
Just have to enter a perimeter value in red till you match with the speed you’ve seen on track.
295 KMH in 5th gear at stabilized 9000 RPM in this case.
After a few times ,you'll be able to build a custom gearbox for any car any track in a few minutes. Easy.
Have a good drive.
><(((((°>°°°°°
Love it at GT5 and loving it for GT6 as well
Happy New Year to you and all home 
Best wishes from Republic of Singapore.
I’ll try to stay as clear as possible.
OK, now you have set the last gear we have a 6th gear ratio at 100%, full right on the panel, and your final gear to reach the speed you need on this track.
To do this visually is not easy because PD take out the graduations on the setting bar that we had in GT5.
