How To Set Gear Ratios (Here's How)

  • Thread starter Gyro1780
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shmogt
I have no idea how to tune transmission, but this is what I do at the moment. I just drive it around some different size tracks and see what the fastest I'm getting is and set the final to a bit more than that. Than adjust the gears to be closer together and a little more spread out for the last few and good to go. Works virtually every time. I have ran into the problem where a car may accelerate too quick and hit the rev limiter while turning in which I just adjust the final gear to make all gears longer and solves the problem.
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This is my way as well. Still, there might be some 1/10 seconds to gain at some tracks, trying to get the changes as close to the optimal rpm's as possible. That's probably all, or..............??
Also, I'm not driving manual, as my fingers don't let me. Maybe if I get a chair, and wheel, I'll do manual. Maybe:indiff:
 
Bugace
This is my way as well. Still, there might be some 1/10 seconds to gain at some tracks, trying to get the changes as close to the optimal rpm's as possible. That's probably all, or..............??
Also, I'm not driving manual, as my fingers don't let me. Maybe if I get a chair, and wheel, I'll do manual. Maybe:indiff:
Click to expand...
Depending on the car/track combo (Nurburgring aside) there can be full seconds gained by gearing.
 
For what it's worth, I've been using a combination of things to set my gears. Time will tell if I've been successful.

Firstly I set FD to as high as it'll go and Top Speed to as low as it'll go. I then examine each gear and note the min/max. I have a simple spreadsheet that I use for this.

Column A lists the gears.
Column B lists (what I call) the 'Multiplier'.
Columns C & D show the min and max ratio for each gear.
Column E is derived from B, C & D "=((D-C)/100)*B+C"

I also have three further columns that have formula derived from Scaff's TuningGuidePart2.pdf. Whilst these three columns are prone to inaccuracy, due to trying to find/guess tyre sizes for any given car, they give you an idea of the speeds you might achieve in any given gear. Combined with using the results of Column E to make a simple chart, I believe you can make a good stab at setting gears.

Finally, the 'Multiplier' is a simple figure between 1 and 100, a percentage. I've found that spreading gears exactly evenly can cause problems with the lower gears. So, for instance, I have an Evo that has the following spread of ratios;

1st 50.0%
2nd 25.0%
3rd 20.0%
4th 20.0%
5th 25.0%
6th 50.0%

This sets my ratios as;

1st 2.989
2nd 2.027
3rd 1.541
4th 1.239
5th 1.047
6th 0.869

With FD set to 4.150, I'm getting the following speeds from each gear (approx);

1st 41.9mph
2nd 61.8mph
3rd 81.3mph
4th 101.2mph
5th 119.7mph
6th 144.3mph

I'm sure there are more scientific ways of doing it, but to be honest, it suits me as I can't afford to get bogged down in the specifics. I just want to pump some numbers in and then change my Multipliers to get ratios that feel good around a track. The above Evo ones are for a car that will spend most of its life off road, so I wanted 2nd -> 5th to be quite close with 1st and 6th a bit longer. Hence my Multipliers.

My Nordschleife LFA has the following spread of ratios;

1st 60.0%
2nd 35.0%
3rd 25.0%
4th 25.0%
5th 35.0%
6th 60.0%

I need more coffee, sorry if the above makes no sense, I hadn't planned on writing it if I'm honest. Just kinda vomited it out... :yuck:

{Cy}
 
Adrenaline
The quickest way, to help gearing...
Set the Auto Top Speed to the lowest possible, usually 124mph I think?
Then set your Final drive to the lowest (numerically) possible, usually 2.000.

This will give you really close gearing in the transmission, with a top speed around 204mph usually.

There are other ways to help the tranny, which usually you want to make 1st and 2nd as long as possible, 6th as short as possible, and focus on equal spacing between 3rd 4th and 5th, as those are the gears you're mostly using while on track. This is the technique that RKM promotes, but it's a bit more time/effort intensive.
Click to expand...

I use above but with a slight modification which I think gives an even closer gearbox.

First I set the auto top speed to the lowest possible (200 km/h normally).
Then I put the sixth gear all the way to the right.
Then I adjust the final gear to what I want the rev to be at the highest speed of the track.

First gear I optimize for the start, normally all the way to the left. This allow the highest power at the right revolution at the start. If (very rarely) I don't get enough rev at full throttle at the start, I modify first gear to the right.
Then I set 2-5 gear evenly spaced between first and sixth. Go to the specific track and make the adjustments based on what rev I want in the different corners.
 
This really isn't necessary. You don't want your gearbox to be purely linear. Instead, in a typical 6 speed, you want your first, second, and third gears to be longer and your 4th gear to be the shortest(relatively, not absolutely), then your 5th and 6th gears to be increasingly longer.

This way you can downshift into corners to gain engine breaking at the rear of the car but still have a high top speed.
 
ampire
This really isn't necessary. You don't want your gearbox to be purely linear. Instead, in a typical 6 speed, you want your first, second, and third gears to be longer and your 4th gear to be the shortest(relatively, not absolutely), then your 5th and 6th gears to be increasingly longer.

This way you can downshift into corners to gain engine breaking at the rear of the car but still have a high top speed.
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I wouldn't set 4th gear shorter than 6th (and in most cases 5th) gear. Acceleration in the high gears would be very bad. If you have problems to get a high top speed, you should try to set 1st-3rd gear even longer (tranny trick?).
 
AssassinTuner
Relax, wasn't talking directly to you for one, second, I think I said autos can be faster than MT. And here is the special part someone so militant about grammar, punctuation, blah blah blah should of caught.

If you can't match your times without the assist (in this case shift assist) you use the assist as a crutch.

You just said you go faster MT, so WTF are you crying about now???

On another note, I really don't take you seriously ever. Not you times or anything, too much of a Hard-On, JMO.

I'll say another thing. Being a manual driver IRL. I've also owned auto daily beaters for convenience, griping the whole time only reconsidering when I'm eating. My girl puts her hand on my lap ;) but I really don't care about that ish when I'm driving. As such I find it hard to take you seriously when you try to pass off the BS it's because your lazy and spend so much time driving various cars. BS, welcome to Gran Turismo, it's LAME AND BORING driving in auto in GT way more so than IRL, anybody who drives MT 4-real & in GT will agree, auto is not only boring, but frustrating.... Anybody who's really good at MT in GT will agree you don't go back... "Lazyness" yeah, okay there, every time you drive MT your faster, yet your posted uber hot laps for your own tunes in your garage all say your using AT and the Driving line. Come on now Bro. Go on proving how fast you are, IDC. You find it hard to take me seriously. That's seriously funny.

Don't trip, I'm not insulting you, I just don't buy your Auto excuse. It's weak, IMO laughable. I'll bet you got enough free time to prove how fast you are MT, get on that. It make no difference to me.

R-R-R as they say, because of this R-R-F...
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Could'nt of said it better my self.
 
CyKosis1973
For what it's worth, I've been using a combination of things to set my gears. Time will tell if I've been successful.

Firstly I set FD to as high as it'll go and Top Speed to as low as it'll go. I then examine each gear and note the min/max. I have a simple spreadsheet that I use for this.

Column A lists the gears.
Column B lists (what I call) the 'Multiplier'.
Columns C & D show the min and max ratio for each gear.
Column E is derived from B, C & D "=((D-C)/100)*B+C"

I also have three further columns that have formula derived from Scaff's TuningGuidePart2.pdf. Whilst these three columns are prone to inaccuracy, due to trying to find/guess tyre sizes for any given car, they give you an idea of the speeds you might achieve in any given gear. Combined with using the results of Column E to make a simple chart, I believe you can make a good stab at setting gears.

Finally, the 'Multiplier' is a simple figure between 1 and 100, a percentage. I've found that spreading gears exactly evenly can cause problems with the lower gears. So, for instance, I have an Evo that has the following spread of ratios;

1st 50.0%
2nd 25.0%
3rd 20.0%
4th 20.0%
5th 25.0%
6th 50.0%

This sets my ratios as;

1st 2.989
2nd 2.027
3rd 1.541
4th 1.239
5th 1.047
6th 0.869

With FD set to 4.150, I'm getting the following speeds from each gear (approx);

1st 41.9mph
2nd 61.8mph
3rd 81.3mph
4th 101.2mph
5th 119.7mph
6th 144.3mph

I'm sure there are more scientific ways of doing it, but to be honest, it suits me as I can't afford to get bogged down in the specifics. I just want to pump some numbers in and then change my Multipliers to get ratios that feel good around a track. The above Evo ones are for a car that will spend most of its life off road, so I wanted 2nd -> 5th to be quite close with 1st and 6th a bit longer. Hence my Multipliers.

My Nordschleife LFA has the following spread of ratios;

1st 60.0%
2nd 35.0%
3rd 25.0%
4th 25.0%
5th 35.0%
6th 60.0%

I need more coffee, sorry if the above makes no sense, I hadn't planned on writing it if I'm honest. Just kinda vomited it out... :yuck:

{Cy}
Click to expand...

That is a good one to try! Thanks!
 
Hey, I'm brand new here...and also still very new to tuning. I'm wondering what all was done to the car in terms of parts/upgrades (if any) because your posted ratios do not match the in-game car - or am I missing something? I tested the figures on a calculator and DID find the figures themselves accurate. I find this whole theory to be very helpful though...except for the inaccurate(?) numbers, it was very well written and I actually learned something.👍
 
Im kind of a tuning noob... and nowhere near the mad scientist some of you guys are when it comes to tuning out flaws in a car. But isnt getting this complicated on gear ratios a bit overkill?

I normally just go for top speed, then factor in a couple extra mph for drafting. After that put first and second gear full left (for any car with decent hp anyways). The rest of the gears I leave alone. I cant really see any reason to bother with anything inbetween. I realize for certain tracks there might be a reason to step outside of this... example the final left turn at deep forest always tends to be between gears for me, so Ill set say... 4th gear a little short so that Im not bouncing the revs in 3rd, but still get a good drive in 4th out of the turn.

Basically though... tall first and second, and the rest I leave alone. Why do anything else?
 
I don't believe you can program a cars' transmission by plugging in a bunch of numbers without taking into account a number of factors. Each car's unique combination of HP/Tires/Weight will lead you to a different set of ratios. You have to account for gearing for 6th or 5th for top speed, 1st gear for a proper launch and then the gears in between. Ideally you want each gear to use the same amount of rpm throughout it's range and for that range to cover the peak of the HP curve.

I can't stress how important setting up 1st gear is. I've won many races just because I set up first gear for launch better than everyone else. Tonight for example I was in a lobby where we ran 4 or 5, 7 lap races in a row at Tsukuba with qualifying. Each time I had the pole in 5 different cars, yet only a tenth or two ahead of the person off-pole, with half a dozen cars within a half second. And each time I got a rocket launch into the first corner, to gain a lead of just a few tenths, but that was all it took to avoid the carnage of being hammered from behind by 2nd place, 3rd, 4th etc. I kept watching behind me as several cars fought it out for position:banghead:, slowing each other down in the process, while I cruised to victory:gtpflag:
 
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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}
 
I wish sometimes I had a 7th gear in my 6 gearbox. I know the car can handle it, as I click upshift often when in 6th.
 
Lambob
I wish sometimes I had a 7th gear in my 6 gearbox. I know the car can handle it, as I click upshift often when in 6th.
Click to expand...

My old SportKA could have done with a 6th gear, man did that thing used to wail on the motorway :ouch:

{Cy}
 
So then what do I do for the vehicles that have more than 6 gears? I've heard that there's a small handful of vehicles that have 7 or 8 gears.
 
rojovo74
So then what do I do for the vehicles that have more than 6 gears? I've heard that there's a small handful of vehicles that have 7 or 8 gears.
Click to expand...

See below...

CyKosis1973
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%

{Cy}
Click to expand...
 
Sorry m8 I forgot the process 4 7 was listed...my bad lol. Anyway, what about 8 gears? I read somewhere that there's at least 1 car in the game, maybe even a few, that have 8 gears - I can't recall what car was referenced though.
 
Adrenaline
That's kind of right... 2 issues though.
1) It's track specific. So unless you want to do it for every single track you run, not that great.
2) 'Max RPM' and 'Max Power/Torque' are not the same. If your car redlines at 8000rpm, but your max power is made at 7500rpm, you want to tune the tranny to hit 7500 just before letting off for the corner, not 8000.
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Good point
 
I know of one tuner that puts the top speed to the left, and the final gear to the left and then adjusts the gears from there. It seems to work well too. 👍
 
rojovo74
Sorry m8 I forgot the process 4 7 was listed...my bad lol. Anyway, what about 8 gears? I read somewhere that there's at least 1 car in the game, maybe even a few, that have 8 gears - I can't recall what car was referenced though.
Click to expand...

For 8 gears, I'd look at spreading them as follows:

1st -> 0%
2nd -> 14.2%
3rd -> 28.4%
4th -> 42.6%
5th -> 56.8%
6th -> 71%
7th -> 85.2%
8th -> 100%

👍

{Cy}

PS - For the pure mathematical route and to know the precise number to enter in each ratio, slap the following into a spreadsheet and save it on your HDD somewhere.

=(("HighestRatio"-"LowestRatio")/100)*"Multiplier"+"LowestRatio"

"HighestRatio" is the highest setting any given ratio has.
"LowestRatio" is the lowest setting any given ratio has.
"Multiplier" is the percentage (%) of the given ratio you wish to use (as I've listed above)

Example:

Assume that on a 6 speed 'box, you have the following range available to you; 1.253 -> 2.765. As it is a 6 speed 'box, you'll only want to use 20% of the available range:

=((2.765-1.253)/100)*20+1.253 = 1.555

moparisgod
I know of one tuner that puts the top speed to the left, and the final gear to the left and then adjusts the gears from there. It seems to work well too. 👍
Click to expand...

Agreed. I've seen a few ways to carry out an initial setup of a gearbox. Sliding Final Drive and Top Speed all the way to the left or the right before setting the ratios is fairly common 👍

The only reason I slide Final Drive all the way to the right is that after I've set the ratios and then start to reduce Final Drive, it usually ends up being quite high. I prefer my Final Drive to be as high as possible to gain as much acceleration as I possibly can. Cars that have low Final Drive, I tend to find are sluggish to accelerate.

As I've said further up the thread, there are a number of ways to skin the cat...

{Cy}
 
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moparisgod
I know of one tuner that puts the top speed to the left, and the final gear to the left and then adjusts the gears from there. It seems to work well too. 👍
Click to expand...

It work too. Everything work, depend what car you`re tuning ,how many gears, power , tires , track...

Just an example to understand my point of view.

Take a FORD MARK IV RACE CAR `67. This car have 4 gears only. With 4 gears it`s difficult to explore the range of RPM where the power is. If it was a 7 or 8 gearbox it would be easy.

So imagine you apply the tranny trick to this car.

Final gear max to the right / top speed mini to the left / spread your ratios 0%-33%-66%-100% / then set again your final gear to have a max speed of 350 kmh = 218 mph.
This way, for the same RPM that the 4th gear reach 350 kmh = 218 mph, your 1st gear at the same RPM reach 196 kmh = 122 mph.

Now do the opposit like the way you are talking about.

Final gear mini to the left / top speed max to the right / spread your ratios 0%-33%-66%-100% / then set again your final gear to have a max speed of 350 kmh = 218 mph.
Now this way, for the same RPM that the 4th gear reach 350 kmh = 218 mph, your 1st gear at the same RPM reach only 123 kmh = 76 mph.


Then you have to play with this depending if you race with a powerfull high torque car with 7 gears or a low power / low torque car wit 5 gears. Need to consider if you need a good launch, grid start or not, the tire you are using, with less grip the car don´t squat......

There is no ideal gears settings , the perfect one for each car stay between this two extremes.

Tranny trick
trtrick.jpg


Opposit tranny trick
notrtrick.jpg


Have a good day.
><(((((°>°°°°°°°°°°°°°°°°
 
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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?
 
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sprplay
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?
Click to expand...
Yes!
Try extreme final gear numbers and you should feel (and hear/see) a difference on straights and especially in corners.
 

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