How To Set Gear Ratios (Here's How)

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Is there any difference how to set the combination of individual gear and final gear ratios, as long as they will result in the same overall ratio?

e.g.

Setup1 (from praianos sheet):
1: 2.821 * 2.565 = 7,236
2: 1.797 * 2.565 = 4.609
3: 1.294 * 2.565 = 3.319
4: 0.933 * 2.565 = 2.393

Setup2:
1: 1.411 * 5.130 = 7,236
2: 0.899 * 5.130 = 4.609
3: 0.647 * 5.130 = 3.319
4: 0.467 * 5.130 = 2.393
(given that you were able to put in theese values)

Theoretically the performance should stay the same, but how will be the effect in-game?

I think it´s possible of course, a simple equation can give you the same result just modifying the gear ratio number staying with the same Final gear. The only thing is that PD sometimes will not give you enough range to set the ratio number for a given gear resulting of the equation.
 
Old thread is old, haters gunna hate.
On topic, long long ago, when RJ and noobster were at it, I tested the above scenario, and the results were faster with lower final drives, leading me to believe drive train effects are involved in the equation. Although this was prior to the test track, it'd be nice to retest, on a more accurate measuring base.
 
I like to use Route X, Speed Test, for 1,000 meter dash, and adjust gear ratios this way on track. The split times change as you experiment with different ratios.

I used to do tranny trick, moving 1st gear all the way to the left, but this was detrimental to Grid Starts on the Nordschleife, the car simply bogs down on Accelleration, if 1st gear ratio is plugged all the way to the left (0%).

Simply raising 1st gear halfway right, across the range, makes for far quicker starts, without affecting much of the rest of the gears.

I still have to learn, how and why moving 1st gear ratio, why it changes feel for the rest of the gears, I suppose it has to do everything with: How fast are you going when you shift at that RPM, and where are you on the track at that point.

FD 3.700 / adjusted to top speed 305km/hr @ 505 pp, is where I usually play at on the Nur.
I am also beginning to favor higher top speed (therefore taller gears, not necessarily wider), to slow the car down in reduced RPM when downshifting, eliminating dramatic instability for power over/understeer if was otherwise downshifting into peak power RPM. Truly a must for Racecars, and high HP cars.
 
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Ok, I have finally gotten serious about gear ratios and transmission and suspension settings in GT5. The problem is (and everyone here seems to have missed this???) GT does not supply adequate information to properly set gear ratios for cars, as the rim and tire sizes are never given. I have been able to guess accurately with some manufacturer data, but without actual data from the game you cannot get precise, at all. So, my questions are:

1. How are you getting rim and tire info to make your calculations, as all the equations I have found for proper gear ratios REQUIRE this info?

2. What in game tools?!? There are none other than tweak a number, run the track, repeat til it seems right, still get your arse handed to you. This takes hours if not days with a single vehicle when you don't have all the data.

3. Why on Earth hasn't someone mentioned the lack of adequate data to Polyphony? I am gonna right after this post. It's ridiculous that they made this game so realistic and kneecap your ability by leaving out critical info for that realism to be consistent.

I have the tuning guide and use this website calculator (http://ctny.audiworld.com/mark/s4/gears/gear_calc.html) to work on the gears, but it's so crazy time consuming that it's turning me off to the game. Sure I want to tweak, but I really want to play more...

P.S. I have already tried most of the approaches in this thread prior to finding it. None are any better than the other, and all take ridiculous time. It should take me minutes and two or three laps to get these set with the correct (complete) information, btw.
 
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Oh, and for the challenged that say that it would be too much work for PD or too much detail, the height, width and length of every vehicle is in the visible car data and is absolutely useless to the game! They could have put standard tire data there instead and spent the same amount of effort on USEFUL data for the game!!! Gaaaaa!
 
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I don't know if it's placebo effect , but I decided to try something different last night, using the Aston Vantage V12 (new DLC car),

I thought.. let's bump up top gearbox speed to 320km for a change, what will that do to my gears.
(I usually always tune them at 290/300)

I then raised the FD, slightly, to lessen the drop of RPM when upshifting.

I was very pleased to discover a new sensation, where I can exit Apex now using existing gear for Much longer time, without the need to shift up, thus perhaps driving uphill in lower RPM, or just losing time to clutch shifts period.

Perhaps I struck a lucky car / experiment, but I am convinced that using existing gears, for a longer time, out of Apex, is my new joy at the Nur. And I will also enjoy a faster highspeed draft to the finish, because there are always epic fast drivers in the lead by 2 or 3s in the games I play.
 
I then raised the FD, slightly, to lessen the drop of RPM when upshifting.

FD has no effect on RPM drop between gears.

The only thing that affects the RPM drop between gears is the space (number) between the gears. ie. 2.500 to 1.500 is a bigger rpm drop than 2.500 to 1.750

rpm drop is calculated as follows:

RPMs of your shift point * (Gear Ratio 2 / Gear Ratio 1 )

So if we plug in 6000 as a shift point in the 1st example above

6000 * ( 1.5 / 2.5 )

= 3600. Meaning we drop from 6000 to 3600 RPMs

if we do the same for example 2

6000 * (1.75 / 2.5 )

= 4200. Meaning we drop from 6000 to 4200 RPMs

What FD *DOES* affect is the ultimate top speed in each gear and how hard that gear pulls (along with the gear ratio)

go forth and prosper ;)
 
There are so many variables to consider when setting up a transmission that it is impossible to ever come up with a one-size-fits-all method or calculator that will be the ideal setup for every car/track. Transmission tuning can be *VERY* involved and time consuming if you choose to really get every last little bit out of a tune.
 
true enough esox, I should elaborate that although when I upshift, the same RPM drop occurs, with constant gear ratios, but the time it stays in the low RPM, lessens, as I raise the FD, due to the FD (is it a cog that changes diameter size? and does it act as a front cog, or a rear cog?)
as in a bicycle for instance. I get most torque, but pedal superfast on the small front cog. as an uphill mountain bike climb.
 
FD has no effect on RPM drop between gears.

The only thing that affects the RPM drop between gears is the space (number) between the gears. ie. 2.500 to 1.500 is a bigger rpm drop than 2.500 to 1.750

rpm drop is calculated as follows:

RPMs of your shift point * (Gear Ratio 2 / Gear Ratio 1 )

So if we plug in 6000 as a shift point in the 1st example above

6000 * ( 1.5 / 2.5 )

= 3600. Meaning we drop from 6000 to 3600 RPMs

if we do the same for example 2

6000 * (1.75 / 2.5 )

= 4200. Meaning we drop from 6000 to 4200 RPMs

What FD *DOES* affect is the ultimate top speed in each gear and how hard that gear pulls (along with the gear ratio)

go forth and prosper ;)

Out of curiosity and boredom I decided to play with this math today.

During which, I came across a few simple questions.
First, for my platform, I wanted to keep it simple, so I used a maxed out NASCAR. Only 4 gears, and an extremely simple powerband: 7000 max tq / 9000 max hp

Question 1: Where is the best part of the powerband to be, in a corner? Do I want to be at max tq, or max power? I assume, I want to Accelerate out of the corner at max tq, and end the straight away at max power?

In the event this is not possible, I assume it's better to focus on the max power at the end of the straight, knowing you see increased RPM/tq on exit?

For the above example, how do you optimize both top speed and off the line acceleration? I can work forwards or backwards in teh equation, but either way, it seems difficult to have both ends match up. For example, in NASCAR I need my top speed to be X, so my Final Gear*4th gear, has to come to an exact number. How then, do you maximize first gear acceleration within those limits?

I suppose Drag Racing is the best example. They have to get off the line with a perfect launch, but still ensure they reach max speed, at max rpm of Max hp... right? Or is there where the 'launch in 2nd' theory comes into play?

I'm going to play around with the a bit more on some more cars, now that I can work through the equation smoothly. Just curious of the above questions. Thanks.
 
There's no need for calculators for simple gear ratio settings.

I've been setting up my gearboxes in the following way for a little while now. Nobody has complained about them yet, and plenty of people have had the opportunity to drive my cars.

Set "Default"
Set Final Drive to the highest it will go (slider full right)
Set Top Speed to the lowest it will go (slider full left)

For the following steps, us the incremental markers on each gear as percentages. Slider fully to the left being 0%, slider fully to the right being 100%.

Set 1st to 0%
Set 2nd to 20%
Set 3rd to 40%
Set 4th to 60%
Set 5th to 80%
Set 6th to 100%

Now adjust Final Drive so that the speed listed in the top right hand corner is approx 10mph higher than you want to car to go. Done.

Obviously for 5 speed boxes you will want to use:
0%
25%
50%
75%
100%

For 7 speeds use:
0%
16%
33%
50%
66%
83%
100%

This is a very simple and common way to setup your gearbox and will do in most circumstances. Obviously though, there are many ways to skin a cat...

{Cy}

👍 Awesome info for those of us that have no idea how to tune, but want to get the most out of our engines. Super helpful for an average Joe like me.
 
👍 Awesome info for those of us that have no idea how to tune, but want to get the most out of our engines. Super helpful for an average Joe like me.

I'm one of those that has little clue about what they're doing..!! These days I tend to tighten up the spacing between ratios, as standing starts will bog down with 1st gear set at "0%". For a standard 6 ratio 'box, I'd split them as below:
  1. Set 1st to 30%
  2. Set 2nd to 40%
  3. Set 3rd to 50%
  4. Set 4th to 60%
  5. Set 5th to 70%
  6. Set 6th to 80%
I've also been experimenting with setting Top Speed first, then Final Drive:
  1. Set "Default"
  2. Set Top Speed to the lowest it will go (slider full left)
  3. Set Final Drive to the lowest it will go (slider full left)
Although this way, I have found that sometimes you don't get quite enough before hitting the limiter, so when setting Top Speed, slide it all the way left, then come back to the right a click or two. That should give you enough room to hit your top speed.

Either which way, this still avoids the necessity of cracking out the calculator. That being said, if you to calculate the exact ratio to input, using the method above, then you can use this cunning spreadsheet I knocked up some months ago. It will require some acurate Googling of tyre sizes...

https://docs.google.com/spreadsheet...GpaSVNmaFpkRUh4eHNka1UzNTZkZXc&hl=en_GB#gid=1

{Cy}
 
Hey!

I cant seem to find a solid practice for creating a successful launch. Whenever I flip the trans, I still end up with a bogged out launch. I must being doing something simple wrong, because it seems like no one mentions anything about successful launch tuning.

Does anyone have a process they use to get a good launch, before tweaking the rest of the gears?

Thanks!

-B
 
Hey!

I cant seem to find a solid practice for creating a successful launch. Whenever I flip the trans, I still end up with a bogged out launch. I must being doing something simple wrong, because it seems like no one mentions anything about successful launch tuning.

Does anyone have a process they use to get a good launch, before tweaking the rest of the gears?

Thanks!

-B
Sure
Tune the suspension first, then find the longest possible first gear which doesn't let the car bog. And only afterwards start messing around with the final gear and other single gear ratios.

Sometimes you can't set 1st gear all the way to the left. Also be aware that choosing a higher bottom max speed gives you a wider range of gears ratios as a whole. The gears won't be as close then.
 
goodnight pilots gt5, without knowing what I'm doing through all these comments, boxes of transmission, relationship end cash, rpm, etc, I say one thing, to get a good transmission box, depends on the circuit, if long or short, if ten ascents or descents, where maximum speed that can atingire and slower depending on if the 1st or 2nd gear, then having these values ​​simply put a sheet cx transmission of gt5, juntanmente with the value of rpm, and she's the exact value of each relationship end and running gear, so I do my box logical that when I can not I want the values ​​I look for posts from my friend praiano63, and nor cal, because edentifico me a lot with the music their,sorry my inglisih hugs.
 
When I set my gear ratios,I change the final gear,change the top speed,change the final again,make my first gear long so i would have a better start,change the gear ratios depending on what track I'm in and I'm in.it make my gear smoother and faster then doing it the old way.
 
Good morning guys, old discussion about the relationship gearbox, its first good placement of how to make a box for min normal but efficient, but not everything was said because it encompasses much math and physics to achieve a good fit because according to box some engineers, has several factors eg, what type of wheel and rim and 19.20 per below, the circuit must rise and decide and various other factors, I personally use several forms but one that I use when I have time to do always seek help from a mechanical engineer and my friend are traveling aualmente but met another through the internet and that more thorough, but very interesting, well mais.abraços

happy new year.
 
There's no need for calculators for simple gear ratio settings.

I've been setting up my gearboxes in the following way for a little while now. Nobody has complained about them yet, and plenty of people have had the opportunity to drive my cars.

Set "Default"
Set Final Drive to the highest it will go (slider full right)
Set Top Speed to the lowest it will go (slider full left)

For the following steps, us the incremental markers on each gear as percentages. Slider fully to the left being 0%, slider fully to the right being 100%.

Set 1st to 0%
Set 2nd to 20%
Set 3rd to 40%
Set 4th to 60%
Set 5th to 80%
Set 6th to 100%

Now adjust Final Drive so that the speed listed in the top right hand corner is approx 10mph higher than you want to car to go. Done.

Obviously for 5 speed boxes you will want to use:
0%
25%
50%
75%
100%

For 7 speeds use:
0%
16%
33%
50%
66%
83%
100%

This is a very simple and common way to setup your gearbox and will do in most circumstances. Obviously though, there are many ways to skin a cat...

{Cy}

Great, works like a charm, toke 0.5sec off my laps times around Tsukuba in my Nissan GT-R R35 TC :crazy:
 
It normally doesn't work for AWD cars.
Launch is still good and so is topspeed?
 
It normally doesn't work for AWD cars.
Launch is still good and so is topspeed?

I'm not sure if my 20/80 split has anything to do with it? Interesting maybe if i polarize it even more 10/90 it would have more of an effect? But i'd be sacrificing a lot of grip then I guess.
 
Some things to consider with this method of tuning:

If you never use 1st gear in slow speed corners, you might be better to tune 2nd gear as tall as possible with slider.

If you only change from 5th to 6th once or twice per lap, you might be better to have 5th shorter.

If you do this, you keep your shifts sharper and you stay in your power zone better for those gear changes you perform most, especially for low power cars at 400pp and 450pp.

Another thing to consider is adjusting only 6th gear when changing to a track that requires a higher top speed.
 
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