Non-Drag Racing Transmission tuning guide

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Otaliema
Non-Drag racing Transmission tuning guide
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There are many very good suspension guides already in existence here at GTP, but I noted that most of them had none or very basic transmission sections. So here I will explain everything I have learned about tuning a transmission for GT6.

First I’d like to thank @Motor City Hami Tuning Guide @praiano63 Transmission tuning guide and @Master__Shake_ ¼ mile transmission guide for the guides they have published they got me started and explained what was needed to make a good car in GT5 and again in GT6.

Other guides that are useful.
The Torque Thread. And other little things you may find useful. by @yannagas
General tuning guide 1.09 by @DolHaus

*Note I will not cover how to build drag racing transmissions other than top speed style. @Master__Shake_ guide covers everything you need to know there. Master has agreed to allow the use of the images from his guide in this one to help with the Dyno screen explanations. Thank you Sir 👍


Index
Definitions
Transmission Types and set up
Building and troubleshooting
Build Examples
Advanced building and troubleshooting *in progress*


A big Thank you to @TurnLeft, @brian wolf, @DolHaus, @ImToLegitToQuit, @Lionheart2113, @Bowtie-muscle, @shaunm80, @TheInfamousJEW6, @Wydopen, @Pete05 for suffering with proof reading and testing the building instructions.
 
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What is a Transmission or Gearbox
Basic terms the Transmission or gearbox depending on what part of the world you’re in. Is a mechanical device that takes high rotational speeds and reduces it to lower speeds and increases the torque output.

The following is a direct quote from Next Generation Technology 4 U Don’t need to reinvent the wheel to explain this right?
To understand the basic idea behind a standard transmission, the diagram below shows a very simple two-speed transmission in neutral
transmission-simple.gif


Let's look at each of the parts in this diagram to understand how they fit together:

  • The green shaft comes from the engine through the clutch. The green shaft and green gear are connected as a single unit. (The clutch is a device that lets you connect and disconnect the engine and the transmission. When you push in the clutch pedal, the engine and the transmission are disconnected so the engine can run even if the car is standing still. When you release the clutch pedal, the engine and the green shaft are directly connected to one another. The green shaft and gear turn at the same rpm as the engine.)

  • The red shaft and gears are called the layshaft. These are also connected as a single piece, so all of the gears on the layshaft and the layshaft itself spin as one unit. The green shaft and the red shaft are directly connected through their meshed gears so that if the green shaft is spinning, so is the red shaft. In this way, the layshaft receives its power directly from the engine whenever the clutch is engaged.

  • The yellow shaft is a splined shaft that connects directly to the drive shaft through the differential to the drive wheels of the car. If the wheels are spinning, the yellow shaft is spinning.

  • The blue gears ride on bearings, so they spin on the yellow shaft. If the engine is off but the car is coasting, the yellow shaft can turn inside the blue gears while the blue gears and the layshaft are motionless.

  • The purpose of the collar is to connect one of the two blue gears to the yellow drive shaft. The collar is connected, through the splines, directly to the yellow shaft and spins with the yellow shaft. However, the collar can slide left or right along the yellow shaft to engage either of the blue gears. Teeth on the collar, called dog teeth, fit into holes on the sides of the blue gears to engage them.

Glossary of terms,
Please read as these terms will be used heavily in the guide.​
Flipping. The first step in setting up your transmission gear ratios.
RPM; Revolutions per minute. How fast your engine is spinning. Your engine generates a specific amount of power and torque at a given RPM.
Long Gear; Gear settings that have a higher top speed, Smaller numbers
Short Gear; Gear settings that have a lower top speed, Larger Numbers
Final Gear; The master ratio for your transmission. The length of all gears is affected when this adjusted.
Torque; The amount of pulling power the engine is generating.
Power; The amount of work the engine can do. ***
Short Shift; Shifting before the normal shift point for a gear, or shifting before Redline.
Long Shift; Shifting after the normal shift point of a gear, or after red line
Power Band; The RPM range the engine is generating the most power.
Torque Band; The RPM range the engine is generating the most torque *may not be a term used IRL but I use it in the guide
Shift point; The ideal RPM to shift to the next gear during acceleration, This is generally the end of the main power band of the car.
IFG/Initial Final Gear; The first thing you set when flipping/building a transmission.

***
Technically power can not be measured from an engine. Just it’s torque. Power can only be calculated. RPMxTorque/5252=Horsepower The amount of work the engine can do is it’s power. Torque is really the only thing that makes you go in any form of movement. walk, running, riding a bike or driving a car.

There are four main ways to tune a transmission in GT6,

Top speed.
indianapolis-motor-speedway-jpg.311170

Acceleration.
willow-springs-international-raceway-big-willow_14-jpg.311194

Drag.

GTR001.jpg

Race.
AplineVGTR001.jpg


Images 1&2 courtesy of @TurnLeft. Thank you sir.

There are many ways to combine them to get differing results depending on what you’re looking for from the tune.
Speed and distance

You don’t need to know how far you have driven in your car or how fast a lap was, just how long some parts of the track are and how fast your car can get to on the track. You mainly need the length of the longest acceleration zone and how much distance you need for some gears. Speed is for setting the top speed slider and adjusting gears during building of the transmission, You need to know how fast the car can get to for your power setup to build the most effective transmission possible.

Use what you’re comfortable with, personally I use km for speed and distance as they are smaller so it’s easier to get things pinned down. Yes feet are smaller than a meter but can’t set that one up separate.

Speed.
There are two ways to use this during the building and they are based on the use for the car. Are you going to build a specialized car or a general use car.
Specialized cars you need to know how fast your car can get to in the longest acceleration zone for the track.
General use cars you need to know the absolute self sustained top speed the car can reach in 4500M, This other than on SSR-X is the longest acceleration zone that I have found on any non player made track in the game, So far. I recommend that you use the absolute self sustained top speed that way if longer tracks come around you’re already set.

Torque and Power
Quick definition Torque is power, horsepower=torque*rpm/5252. Most modern car engines generate their peak torque at lower RPM’s so you don’t have as much power to the wheels. Which means less wheel spin, less wheel spin means more effective acceleration. Higher RPM’s give more power even with the reduced torque of each RPM this allows the engine to push the car through the air resistance, upto the maximum the power can do.

Transmission and Wheel torque
Your transmission does one thing in the car, it multiplies the engine torque to the wheels. In reference to gears the smaller gear number the smaller the gear is physically meaning it can go faster which allows the car to reach higher speeds. This is something to consider while building your transmission if you’re having wheel spin problems you’re over torquing the wheels past their maximum grip levels and a reduction in the gear ratios is probably in order to solve this problem. Or you’re lacking enough get up and go a increase in gear ratio is in order to get some more get up and go.

It’s an easy formula;
Final Gear*Gear=Ratio
Ratio*Torque=Wheel Torque For that gear
Now this number you will get is theoretical, and is assuming no losses in the transmission due to friction. We don’t know if PD programmed it into the game, if you want to make that assumption. Multiply your torque by 0.85 as the most common accepted number for street cars is 85% power efficiency

So 0.85*Torque*Ratio=Wheel Torque

See How does gear ratio affect torque for an off site reference.


Now I’ll save you some effort here. The final gear ratio does play a part in the acceleration of the car. The shorter the final gear the longer the gear has to be to get to high speeds thus slowing down the car. So even though setting your final gear to its longest setting and the Top speed slider to the maximum value will give you insanely high ratio numbers and thus very high theoretical wheel torque, your acceleration will not be what it is if you keep the gears short using the standard flip methods.

Flipping your transmission
You’re setting your transmission for tuning and use.
To help understand this in simpler terms. Think of a 6 speed bicycle. The Final gear is the the main ring of up front. The smaller the ring (a shorter gear) the less power you have to put in to make the bike go, but the faster you go the more times you have to turn the ring to keep you going. Your Gears are the set of rings on the back wheel. The larger (short gear) the ring here the less power you need to make the bike go, but the gear has to complete more revolutions the faster the wheel is spinning. Now if you switch the ring sizes front to back you get a set up that takes a lot more power to get going but is easier to keep it going faster. This is the mechanical advantage of the gears. Relation for simple in game, the Final drive number is the number of times the Main drive gear (final gear) turns over per revolution of the engine. The gear number is the number of times the drive shaft is spinning per revolution of the final gear. While not technically correct it’s the easy way to think about it.


To flip your transmission set you set your Initial Final gear (IFG), than set your top speed slider.
A longer Final gear gives more torque for the transmission to work with but less speed. A shorter final gives more speed but less torque.

How this applies in game;.
The longer the Final Gear starting point the faster the car accelerates because the car is gaining more torque from the transmission but the top speed is lowered as the engine has to work harder to keep the car going. The shorter the final gear the higher your top speed but the slower it accelerates because the torque output is lower so the engine has to work for a longer period of time to get you going.

Engine parts
In GT6 your gears are based on the maximum RPM of your car, when adding power parts be advised that all of the following parts add or remove RPM and will affect the gearing of your car.
Engine 100 RPM per level of upgrade installed or uninstalled
Sports Computer 200 RPM when installed or uninstalled
Exhaust 100 RPM per level of upgrade installed or uninstalled
Catalytic Converter 200 RPM when installed or uninstalled
You can add or remove up to 1000 RPM to your car

The Exhaust Manifold and Intake tuning just add power and torque.
It is possible to build a transmission that will be the same on every RPM change, But your working range for each gear is very small. It can be very tricky to do this well. See the Advanced building and troubleshooting section


Turbo kits and superchargers.
These actually move the power band of the car, this needs to be considered when building your transmission to maximize the acceleration and speed.

Finding the power band of the car. Using the Dyno screen on the left side of the tuning window. Power (the blue line) and Torque (the yellow line) bands. The max values are shown and have a line drawn to them on the respective line. So we do have RPM references if you looked at the garage data prior but this numbers change with parts installed. Minimum RPM is shown left and maximum RPM is on the right.

Graph.png


*Dyno screen Theory*

*under revision*
Car being used for example; RE Amemiya FD3S RX-7
Garage data Max power 366 HP@ 6900 Max torque 346.4 ft-lb @ 5000

Each segment is worth about 1075 RPM So for the sake of rounding we will call it 1100 RPM per break down. Counting from Right to Left
Line one is 7500 RPM, line 2 is 6400, line 3 is 5300 line 4 is 4200, line 5 3100 line 6 2000 rpm.
Now counting Left to Right it takes 6.5 lines to go from 0 HP to 383 HP, it’s a pretty linear line so we can use basic math to get to get a rough estimate on power available at peak torque. 383/.6.5=58.92 HP per segment, so 59 HP. Remember these are guesstimate figures not exact figures. The line as you can see it is much flatter from 5100 to 7000 than 0 to 5100. So just looking at this we would like to get the gears to use most of this range, so target RPM’s for gears is 5000 RPM shift to and a shift point of 7500 RPM. 2500 RPM per gear, large range of good power.
A much much more effective way (well a easier way) to get the power band is this.
Goto SSR-X, Set the final drive as short as it will go, set the top speed as low as it will go, than move the final gear as long as it will go.
Set to manual transmission if you normally use automatic.
Hit the track, Come to total stop on the track. make sure you’re in 1st gear for low powered cars, 2nd gear for mid power 3rd gear for high power and 4th gear for very high powered cars.
I recommend using bumper cam for this with the HUD displayed. You can do this in replay as well if you prefer a different cam and don’t want to mess with it.
Now let go of the brakes and e-brake, then floor it. watch the tach, and your speed, you will see a notable increase in speed gains at a particular rpm, and you will see a notable drop in speed gains at particular rpm this is your power band, you want your gears to function 100% of the time in this range, in a perfect world anyways, so say 95% of the time 👍
If you’re unsure of the RPM’s complete the lap save the replay and use the data logger full version or i2Pro you can isolate the RPM and speed there with more detail.

Sadly the Dyno screen in GT6 is lacking really good information but it is what we have to work with so you need to learn to read it. All dyno screens are broken into 8th’s so the value of each segment changes based on the RPM of the engine. The middle of each dyno is broken in 6th’s with lines, the edges of the box are 0 and Max. We have no reference for the torque and power figures other than maximum values. So some trial and error is required to find the actual RPM’s that are useful for a car with a set of power parts and limiter set up.

goodtranny2.png

The first and second gears are long, third gear is mid fourth gear short mid and fifth gear is short. It has been stretched out for high speed.

You want to try and keep the gears spaced around the main power band of the car. This can be a challenge but it is easily doable with practice and a little bit of mental imagery. Taking the two pictures above you can get a very good idea of how the gearing will work with the car.
goodtranny.png

As you see the gearing covers the entire power band and then some. This will cause the car to bog down a little bit as you shift but will also allow for smoother shifting in a racing situation helping keep the car stable. It is possible to get the same top speed as this one with a tighter grouping of gears. This will cause the car to be a little more unstable on shifting. Very tight grouping of gears is best for time trial cars as you are going for maximum speed and if you ditch it you just try again.
tranny001.png
tranny002.png
 
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Transmission type names​
A short definition. At least what I call them.
Top speed; a short final drive flip, appropriately set top speed for the car, shorted gears and then is lengthened to reach the top speed or a car.
Drag race; Long Final Drive flip, appropriately set top speed for the car, long mid and short gears to maximize acceleration and minimize wheel spin from a standing start.
Acceleration; Long Final Drive flip, mid set top speed, mid to short gears, to minimize wheel spin and maximize acceleration in the low to mid range of the car.
Acceleration Race;Mid-short Final drive flip, long, short, long gears to minimize wheel spin and maximize acceleration through most of the speed range and still hit a good top speed on the longest straight.
Top end race; Short Final Drive flip, low top speed, long, mid and short gears to use as much of the power band as possible and minimize wheel spin.
Race; Mid final drive flip, mid short top speed, long, mid, long gears to maximize power band use and speed.
Time Trial; Transmission build based on track, most commonly one of the Acceleration types.


Setting up your transmission.

First of all you need to decide what is this tune being used for. Is it going to be a generalist, or a specialist for tracks. Time trial, AI racing or Online racing.

How to break down a gear for the terms Long, medium, short.
I will use the final gear ratio for this explanation, the principles of the how, work for every gear regardless of numbers, it’s just easier with the final gear to explain because it’s always a round set of numbers

The most common final gear I see has a range of 2.500 to 5.500, with a 3.000 move range. I will just remove the decimal for this explanation so 2500-5500, 3000 point range.

I find the dead middle first.
3000/2+2500=4000
Next break the adjustable range into 1/3’s
3000/3=1000 per range.
The dead middle of the gear is 4000 and we know the gear has 3 1000 point ranges, so from this we can figure out the ranges. Terms of Short-medium or medium short, medium-long and long-medium. They are +/- 250 point from the change over from Short to medium and medium to long.
Short range is 5500-4500
Short medium to Medium Short 4750-3750
Medium range 4500-3500
Medium Long to Long Medium 3750-2750
Long range is 3500-2500


Transmission Types
All transmission types can be broadly grouped into the Generalist or Specialist categories.
Generalist transmission are what they sound like they are good at many tracks and many racing types.
Specialist transmissions are built for one track or distance, each gear is set up to maximize power to the track, speed and minimize shifting.

Specialist only transmissions
Drag Racing
Top Speed
Time Trial

Generalist only transmissions
Any type of Race transmission.

For Career mode and non drag/top speed racing You will want a Race type generalist transmission. It won’t be perfect for any track but will work for all the tracks, you might have to short shift for a set of esses or long shift a hair pin. But you will always be able to find the right gear for a corner with it.

For seasonals; A-spec you will want to build a race type track specific transmission. Hot lap and super lap you will want to build a Time trial transmission.

General transmission rules​
These are good rules of thumb and can be bent as needed.
Gear ratiosAs I mentioned above your gear ratio is Final Gear*Gear=Ratio, Ratio*Torque=Wheel torque
Reverse
Wheel Torque/Torque=Ratio
Ratio/Final Gear=Gear
Ratio/Gear=Final Gear


This is important as the better your ratio the better the acceleration, up to to the point of maximum grip. Basically the higher the gear number and the higher final drive number the higher the ratio will be, the higher the ratio the more torque at the wheels you’re getting.
Ratio*Torque=Torque at wheels. Torque=acceleration, Acceleration=speed.

Now you can use this information to help cut down wheel spin, if you are constantly having problems with wheel spin in say 1st and 2nd gears and part of 3rd gear. You can do some quick math to find out the torque 3rd gear is making and rebuild so 1st gear is below that number. Remember cars weight more the faster they are going due to aero effects, thus increasing the tires grip, Also suspension settings on the drive wheels can affect your overall grip levels as well.
Troubleshooting example using the problem above. Let’s say the car has 250 ft/bs torque and 500 HP.
1st 3.189
2nd 2.590
3rd 2.150
Final 2.500
We know it stops spinning it’s tires about mid way through 3rd gear.
2.5*2.15=5.375 ratio
5.375*250=1343.75 wheel torque
we want to get below this number so lets drop the torque by 300 ftlbs
1043.75/250=4.175
4.175/2.5=1.670
Judging by the that number it would be more feasible to make 2nd gear closer to this number and have it longer by having a shorter 1st gear, thus reducing the shift in torque of 2nd gear. We could in theory goto a 2.200 ish second gear with a 5.450 1st gear to reduce the wheel spin we will still get some but it won't be near as much or for as long thus improving your acceleration.

To do this go back to your flip point on the final gear and increase the top speed slider until you can reach this number as the longest point in 2nd gear. Sometimes you will have wheel spin and you can’t do anything about it other than throttle control, adjusting the suspension or using traction control.

Race type transmissions you will want a medium speed shift that is not incredibly sharp or brutal on power delivery. This is help the car maintain control and allow you recover if needed. You want your transmission longer than your car can power on it’s own to allow for drafting room. The amount of space you need is based on how long the longest straight is. The longer the straight the more space you want, but you always want to be able to maintain speed with no draft in your final gear.

Acceleration type 1 Each gear needs to be set to use the best part of the power band for the speed it will be used. So long 2nd gear medium long 3rd medium 4th short 5th and medium short 6th gear. I know I just contradicted myself right? No, the big problem the acceleration type transmissions have is lack of top end so backing 6tth gear off longer than 5th gear gets a better mix of torque and power at high speed which will allow the car to continue to accelerate at a decent rate. I generally will set 6th gear to appear level with 4th gear. this technique also allows for shorter gearing 2nd-5th to get better acceleration.

Acceleration type 2
This is type of transmission that is based on getting the quickest shift possible, it’s not friendly to twitchy cars or auto users as the shifts are short harsh and can make a car unstable. I don’t recommend this transmission for the beginner as it can and probably will cause you to spin. Gearing style is based solely on the power band of the car as you need short gears you don’t have much play room.

Acceleration Top speed
It comprises some of the elements of a Type 1 and Type 2. With a notable difference. the final gear is long. On a six gear car it will be as long as third gear most of the time, maybe just a bit shorter. You are looking for a medium long, long, short-medium, short, short, medium long style build. This gives you great acceleration and top end in the same build. Note you do not want the final gear to drop out of the power band by more than 100 rpm, or you will bog on speed affecting your time and your overall top speed.


Endurance
These are best built with a Race build so you can overstretch the transmission for fuel saving and tire spin reduction.

Specialist Transmissions​
Time Trial
In general you will be using a Acceleration build for these, but you will adjusting gears to corners and corner sets as you’re trying to minimize shifting as that costs time and maximize acceleration and top end in the same tune. One of the main differences on this one is you want short, sharp brutal shifts to get the power back to the track as fast as possible. See the acceleration type 2 for build and troubleshooting. Important difference. You want the gearing to hit the end of the power band at the end of the longest straight not the middle of the power band.

Top speed
You want to get as much mechanical advantage as possible here to gain as much pull as you can get, acceleration is not as important with these as we going for top end. See the top speed build and troubleshooting below for details.

A-Spec seasonal
Build your choice of transmission and see the Acceleration type 1 troubleshooting if needed.

Drag Race
I will not cover this one as there is already a fantastic guide for them.
 
Building and troubleshooting

General rules that apply to all transmissions​
Establish the top speed the car will reach.
Set the final drive based on the type of transmission you’re building.
Set your top speed one click higher than you just established as we are optimizing the gears so we will be going faster.
Spread your gears based on the power band, if you’re a manual or auto user or building for general use.*Top speed builds don’t have a difference due to the build type. Max speed is the goal time to speed is irrelevant.

Top End Race​
For this explanation I will use a 6 gear set up as this is the most common.
These transmissions are fairly simple to set up. Set your final drive as short as it will go, set your top speed and low as it will go. Now set the gears as follows as a basic setup. Set your 6th gear as short as it will go. Set 5th gear as short as it will go. Set 2nd gear as long as it will go, now balance 3rd and 4th gears to get a nice liner line from 2nd to 6th. Now Adjust the final drive for the track you’re at. Take it out and give it a good run, note when it’s shifting, how is the car accelerating through the gears etc. See the troubleshooting below to fix any issues. Now a Top end race transmission need to keep it’s acceleration in 1st and 2nd gear when at the top speed of the car. So head to a track the car can reach it’s speed at that you’re likely to race on.

Keep adjusting the top speed till you find the maximum speed the car will hit for the longest straight, Now build the transmission.
See troubleshooting below.
Top speed troubleshooting.
Did the car accelerate through all gears well and have room for drafting? Yes; You’re done No; see below
  1. Did it bog down 1st-3rd? Shorten the gears by 0.010 per 500 rpm it falls from the power band.

  2. Did it bog down in every gear but still made it to 6th gear and maintained speed? Not much you can do the power band is too small for the transmission and power of the car. Suggestions; Rebuild the car at a lower PP or shorten the final drive till the shifts are inside the power band of the car and deal with the lower top speed.

  3. Did fail to reach it’s final gear or fail to maintain speed after shifting to final gear? Shorten the final drive 0.100 per 500 rpm you’re off from shift or maintaining speed.

  4. Was it bouncing off the rpm limit in 6th gear and your final drive is as long as it will go? rebuild with a higher top speed setting. Increase speed by 3 clicks and check again speed again. Repeat until it fits the rules for a race type transmissions.

  5. Was it spinning the wheels easily? Yes continue below

  6. Was it in 2nd only? Yes; Are the gears at maximum length? Yes you need to throttle control the car or rebuild the transmission with a higher top speed. See below for information on determining how much to increase by.

  7. Did the car spin the tires in 3rd gear? Yes; Was in straight line acceleration?No see #8 Yes; is it as long as it will go? Yes Increase top speed by 3 clicks. No; Lengthen final gear.

  8. Was it spinning coming out of corners. Yes; Is it as long as it will go? Yes Increase top speed by one click.

  9. Did it get to the end of 6th gear but struggled to do so? Yes; Lengthen the gear by 0.010 per 100 rpm to start of power band.

Top speed car​
The ideal gearing for this transmission setup is a couple hundred RPM past the peak power in the last gear, that way you’re not struggling to get that last few km/h. Use the top speed setup. install all your desired power parts first. Than set the final drive to the shortest it will go. Set your top speed slider to the midpoint of its range. Than set each gear to the shortest setting. Move the Final drive to longest it will go and take it to the track, Recommend SSRX as it’s the only place a car can hit it’s true self sustained top speed. Go until it won’t accelerate or slow down anymore. Take notes of what was going on during the drive. If you’re using Nitrous oxide, or NOS, you will need to test how much it boosts your final speed by setting the top speed higher than you anticipate the car reaching. most cars with nos will gain about 20-50 km/h. If your car gains more than 30 km/h on this speed test, add 10 km/h to that with proper gearing.

See below for troubleshooting.
  1. Was it dropping out of the power band, bogging down or hesitating on most or all shifts? Yes;see #2 No; Continue until you have covered all troubleshooting

  2. Did it reach the last gear? Yes see #3, No; see #6

  3. Was it bouncing on the Rev limiter? Yes 7, No 4

  4. Was it at or just past max power? Yes 5, No 6

  5. You set the speed and gears correctly, the power band is too narrow for the car for the power it has. Solutions; Reduce the top speed of the car to shorten the gears to keep them inside the power band to keep the acceleration up for top speed racing. If this is just a speed car to get as fast as possible then no changes are needed as how long it takes to get the speed is not important.

  6. Your speed is too high, go back and rebuild with a lower top speed setting on the slider. 2 Clicks down per gear short. If in your last gear do one click.

  7. Your speed is too low. To determine how much to raise it by;

  8. Did the car accelerate through the last gear as easily as the previous? Yes; Increase by 3-5 clicks up No; see #9

  9. Did the car struggle at the end of the gear and it’s just bouncing? Yes; Lengthen the last gear by 0.020 till its not hitting the rev limiter. If it starts to drop out of the power band adjust speed slider up by the same speed gained +1 click. The increased range of all gears will bring the last gear back inside the power band.


Acceleration Race Type 1​

This is a good all around build for most cars it gets you up to speed faster, it holds speedwell, and odd as it sounds it generally has a higher top speed at the end the longest straight than normal race style transmissions. The reason is it gets through the bottom end faster so you have more track to get the top speed out of it. Building is deceptively easy. First you need to know how fast the car gets to on the track adjust the top speed slider and take it for a spin till it’s just hitting the middle of the power band in the last gear. Now set the final gear to 1.000 from the longest setting. Now set the top speed one click up from what you found in your speed testing.
Now set 2nd gear the longest it will go. Set 5th gear as short as it will go. Now balance 3rd and 4th gear to give a smooth curve up. Now set 6th gear equal to 4th gear. Leave 1st as is, or shorten a bit. Now take it for a spin. Now set the Final drive to just past where 6th gear was after your speed testing.

Troubleshooting
Review your cars performance over the entire gear range.

  1. Did it bog down in any gear? Yes; short that gear and re-space the gears after it.

  2. Did it reach the correct place in the power band location in the last gear? Yes done. No;

  3. Did hit the rev limiter? No, see 4, Yes see 8

  4. Did it come up short of the desired location? Yes rebuild with a shorter Initial final gear. Adjust final gear by shorter 0.050 per 100 rpm you’re short of desired location. No see 5

  5. Did go past the desired point but not hit the rev limiter? Yes, See 6 No see 8

  6. Where all other gears well balanced? Yes; lengthen 6th gear by 0.020 per 100 rpm you’re over shooting the middle of the power band. No see 7

  7. Where the gears all a bit long? Yes see 4 No see 8

  8. Where the gears all a bit short? Yes, rebuild with a longer initial final drive. Adjust final drive longer by 0.050 per 100 rpm you’re coming up short.

There you have the troubleshooting for a generalist type 1 acceleration transmission. below will be the steps for a track specific build. You need to rebuild the transmission from the ground up, You want to set the initial final drive as low as you can get it and hit the middle of the power band on the longest straight with the Final gear at the longest setting it can go. Complete the generalist troubleshooting steps 1 & 2. Now look at the track and the gears you were in for the track, shift points, and average RPM’s in the turns. Generally speaking a higher RPM will turn a car better than a low. Some exceptions apply such as turns 3 and 4 at High Speed ring where you want to mid RPM to get the car torqued around the flat turns.

  1. In the rhythm section of the track where you in between gears, basically bouncing the rev limiter. Yes, pick which gear you want to be in for that second and adjust by 0.020 longer if you’re closer to red line per 100 rpm you need to get the gear in the best response section part of the power band.

  2. Were you having to shift shortly before a turn? Adjust the run up gear longer by 0.100 per 30 meters needed to get to the breaking point for the turn. Note you will be going faster by doing this so adjust your breaking point accordingly.

  3. Has the gear has been optimized for a different set of corners? Yes pick a different gear for the corners or rebuild the transmission one click higher on top speed to gain more speed in the gears.

  4. Is the gear the longest it will go? Yes. Shorten the gear by 0.100 per 30 meter you’re short for the shift. to gain more time in the next gear.

Repeat the above steps till you have the transmission smooth not bogging down and not short shifting or over running a gear


Acceleration Race Type 2​
This is again a deceptively simply build. The main difference between a Type 1 and Type 2 is the initial Final Drive and Top speed settings. With this build you want to use the lowest top speed to get short tight gears and lowest final drive that will get the car to it’s top speed and be in the middle of the power band of the last gear. Now space the gears evenly getting progressively shorter until the last gear.

Troubleshooting
  1. Did it bog down in any gear? Yes; short that gear and re-space the gears after it.

  2. Did it reach the correct place power band location in the last gear? Yes done. No;

  3. Did hit the rev limiter? No, see 4, Yes see 8

  4. Did it come up short of the desired location? Yes rebuild with a shorter Initial final gear. Adjust final gear by 0.050 per 100 rpm you’re short of desired location. No see 5

  5. Did go past the desired point but not hit the rev limiter? Yes, See 6 No see 8

  6. Where all other gears well balanced? Yes; lengthen 6th gear by 0.100 per 100 rpm you’re over shooting the middle of the power band. No see 7

  7. Where the gears all a bit long? Yes see 4 No see 8
Where the gears all a bit short? Yes, rebuild with a longer initial final drive. Adjust final drive longer by 0.050 per 100 rpm you’re coming up short.


Acceleration Race Top Speed​
For this build, you are going to be combing the Acceleration Type 1 and Type 2, and little bit of top speed race builds. To start use the Type 2 initial final gear and top speed slider setting. Now use the Type 1 gearing for first and second, Long and Long medium. gears three four and five need to be spaced and set like a type 2 transmission. short and fairly tight. Sixth gear is set like a top speed car, Medium. Now the building of the transmission is not that simple. You want to use first gear with this build to get the maximum acceleration from the car. So set first gear as long as it will go. and set 5th gear as short as it will go, now level 3rd and 4th gears with 5th gear. Balance 2nd gear with even spacing between 1st and 3rd. This will alter 3rd gears placement to 4th. Don't change it. Now Set 6th gear even with 3rd gear. This set up is a Long short long design. It provides maximum acceleration with maximum top speed in the same build. It does cause a lot more shifting. For troubleshooting see the correct transmission type for the problem gear(s).
 
Build example

Here I will explain the power band and gearing set for a RE Amemiya FD3S RX-7, go grab yours, it’s a career win car. National A (All Stars) gives RE Amemiya FD3S RX-7 - 100,000 Cr in case you haven’t gotten it yet. Slap a Racing exhaust on it.

Now with the information on how torque and power work, we need to build the transmission around this. so gears 1-3 should use most of this range so long gears. Gears 4 and 5 should use the HP section so short gears and gear 6 should use most of this band as we need more torque at at high speed to help pull the car through the air resistance.

With a setup like this we can take advantage of the functions of torque and power when they are most useful. Torque at low speed, power at high speed, and combo of both at upper limit of the engine's capability for speed.

Note to Automatic users, This car is much faster in the hands of a manual user as we can shift when the power starts to wane. Auto users have to suffer through 500 or so RPM of massively dropping power and torque before it shifts for them. So now what right? ideally we can set up 2000 rpm range gears for this car for every gear but an auto user is going to get killed in 4th & 5th gears waiting on the shift. There is a simple answer, make 4th & 5th gears short about 1500 rpm long enough to make the shifts worth it but short enough it will shift to the next gear before they really start hurting for power at higher speeds. Then use the 2000 rpm 6th gear to get the speed.

If you don’t tune for this and run in automatic mode this will be a 4 or 5 gear car on most tracks and 2-4 seconds slower.

Auto build examples;
For the RE Amemiya FD3S RX-7 to get the best acceleration from the car we need to build the gearing like this Short, Long, Long, Medium-Short, Short, Medium This keeps the car out of first gear, gets the power down at low speed without much wheel spin, Short gears to get it through the bad power at speed and longer gear to reach top speed.

For the Tommykaria ZZII we could set up the gears like this
Short, Medium-long, Medium, Medium, Medium short, This gets the power down at low speed and at high speed without much wheel spin.

Manual build
RE Amemiya FD3S RX-7;
Long, Medium-long, Medium, Medium short, short.
Tommykaria ZZII;
Medium-short, Medium, short-medium, short, short. short.

Now while I’ve only covered a few of the transmissions here. The basics are the same for every type of transmission I’ve come across just refer to the definition portion for setting your initial final and top speed settings.

Sometimes trial and error are the best way to do things in GT6 and this holds true with transmission getting the right power band, or gear length for a set of turns. As you build more you will start to see patterns what types of power bands like which type of set up. You will have your favorite type, that works on most cars. It’s a good feeling being an equal car to someone else and just pulling away because the transmission is better.
 
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Advanced building and troubleshooting



Manual and Automatic transmissions

Building your transmission you need to consider if you’re a manual user, or automatic user. Manual users can shift to get out of tire spin, or take advantage of mid power band. Automatic users are at the mercy of the shift point for a gear. This means gears that are too short will cause lots of wheel spin at low speeds and if they are too long horrible acceleration at high speed.
Manual users can optimize the transmission to the track, hold a gear for a turn shift at the best rpm.
Automatic users we need to take a look at the cars power band. Are we going to have 500+ rpm of diminishing power till it shifts or are we going to be at full or nearly full power until it shifts?
Looking at the RE Amemiya FD3S RX-7 from prior it’s power drops off considerably at 7500 to 8200 rpm’s. Look at a Tommykaria ZZII it’s power is solid right to the end. When a transmission is built you will find the following to be true with the cars.
The RX-7 needs a automatic transmission build and a manual build.
The ZZ II’s can get away with the same transmission on both manual and automatic. Some considerations should be made on the ZZ II for an automatic user such as 2nd should be a bit longer than on a manual car


Full range transmissions
On occasion you will have a great car that works over a large PP range. Wouldn’t it be great to have a transmission that does the same? I agree, here’s how to set it up.
Pick your build style, set the final drive and top speed accordingly accordingly.
Now remove all engine upgrades that increase the RPM of the car.
Set your high gears as short as they will go on a six speed gearbox gears 4-6.
Now install all RPM increasing parts on the car at top level. You should add 1000 RPM to your engine.
Toggle your tune page. eg Switch to page B then back to Page A.
Set gears 1-3 as long as they will go.
Remove all RPM increasing parts and toggle your tune page.

Now look at your gears. You will see 1-3 sliders are moved to the middle a bit and 4-6 are all still pegged short.
Now tweak the gears 1-3 shorter, 4-6 Longer to get the gears set up right.
Install all RPM parts again and toggle the page.
Check and tweak again. remove all parts and toggle the page.
You may find it beneficial to jot down the min/max for the gears at both maxed and factory RPM’s so you can stay within them and not have to toggle the tune page to make sure everything stays put.
 
Well done my friend. That's certainly a very comprehensive guide to anyone looking to understand how building a transmission in GT.

99.9% of the race cars in my garage have had a transmission flip performed on them. It's only the few cars that have real world ratios that escape the flip.
Once I've performed the flip, I then do a little more fine tuning of the individual ratios and set them in stone, never to be adjusted again. I then test the car at various tracks and make a list of final drive ratios suitable for each track in racing conditions, allowing enough room for slipstreaming on the longest straight.
 
Well done my friend. That's certainly a very comprehensive guide to anyone looking to understand how building a transmission in GT.

99.9% of the race cars in my garage have had a transmission flip performed on them. It's only the few cars that have real world ratios that escape the flip.
Once I've performed the flip, I then do a little more fine tuning of the individual ratios and set them in stone, never to be adjusted again. I then test the car at various tracks and make a list of final drive ratios suitable for each track in racing conditions, allowing enough room for slipstreaming on the longest straight.
Solid racing style transmission setup techie. Try the acceleration race set up might find another few hundredths for you. Mere mortals like myself can gain a tenth over a normal race set up
 
Nice, uuh, rocket science tranny flipping.
I'll stay on excel sheets where you can just input desired rpm drop on all gears and go :)
Similar to this:
Screenshot_2015-11-26-04-01-18.png
 
That's cool. How does one go about converting speed to gear ratio in GT6? With variability of ratios due to rpm, final drive and speed slider?
Hit first desired final with testing straight gear and and possible mild overdrive, engine pull to redline, under minute search to select settings on gearbox to get wanted ratio ranges visible, even less time if using "wrong"finalgear liike trannyflipping does.
There is also few even lazier gearcalculators made for GT-series, there you just input gear scale and it counts using your wishes of how box need to be made.

Flipping makes easy approach to get tight gear spread, that same spread is there without flipping too.
 
Am I reading that right? A car that can go 120mph in 1st gear @ little over 8,000RPMs?

Edit:
Do you remember what car that was?
It's a exemple, values aren't from game or relevant to it, you can go and test box made for FD35 using my favourite calc, quick setup, shifting from 1st and 2nd on redline, 3rd from recline or slightly under, 4th 7500 or near (when acceleration starts to go slower), from 5th around 7400 or slightly under. Only oil changed engine. Change top speed slider and insert value.
IMG_20151126_152129.jpg
It's generic box, Nordschleife included.
 
Advanced building and troubleshooting



Manual and Automatic transmissions

Building your transmission you need to consider if you’re a manual user, or automatic user. Manual users can shift to get out of tire spin, or take advantage of mid power band. Automatic users are at the mercy of the shift point for a gear. This means gears that are too short will cause lots of wheel spin at low speeds and if they are too long horrible acceleration at high speed.
Manual users can optimize the transmission to the track, hold a gear for a turn shift at the best rpm.
Automatic users we need to take a look at the cars power band. Are we going to have 500+ rpm of diminishing power till it shifts or are we going to be at full or nearly full power until it shifts?
Looking at the RE Amemiya FD3S RX-7 from prior it’s power drops off considerably at 7500 to 8200 rpm’s. Look at a Tommykaria ZZII it’s power is solid right to the end. When a transmission is built you will find the following to be true with the cars.
The RX-7 needs a automatic transmission build and a manual build.
The ZZ II’s can get away with the same transmission on both manual and automatic. Some considerations should be made on the ZZ II for an automatic user such as 2nd should be a bit longer than on a manual car


Full range transmissions
On occasion you will have a great car that works over a large PP range. Wouldn’t it be great to have a transmission that does the same? I agree, here’s how to set it up.
Pick your build style, set the final drive and top speed accordingly accordingly.
Now remove all engine upgrades that increase the RPM of the car.
Set your high gears as short as they will go on a six speed gearbox gears 4-6.
Now install all RPM increasing parts on the car at top level. You should add 1000 RPM to your engine.
Toggle your tune page. eg Switch to page B then back to Page A.
Set gears 1-3 as long as they will go.
Remove all RPM increasing parts and toggle your tune page.

Now look at your gears. You will see 1-3 sliders are moved to the middle a bit and 4-6 are all still pegged short.
Now tweak the gears 1-3 shorter, 4-6 Longer to get the gears set up right.
Install all RPM parts again and toggle the page.
Check and tweak again. remove all parts and toggle the page.
You may find it beneficial to jot down the min/max for the gears at both maxed and factory RPM’s so you can stay within them and not have to toggle the tune page to make sure everything stays put.
Long project, well done and well written. Great job, this should be EXTREMELY helpful to the tuning community.
 
Long project, well done and well written. Great job, this should be EXTREMELY helpful to the tuning community.
Yes it was a long project. What close to a year between all the rewrites? And I still need to rewrite the Dyno theory section, lion heart found some interesting changes a month back that I haven't had time to investigate
 
It's a exemple, values aren't from game or relevant to it, you can go and test box made for FD35 using my favourite calc, quick setup, shifting from 1st and 2nd on redline, 3rd from recline or slightly under, 4th 7500 or near (when acceleration starts to go slower), from 5th around 7400 or slightly under. Only oil changed engine. Change top speed slider and insert value.
It's generic box, Nordschleife included.
I'll have to give those numbers a go and see what it does to us auto users. As much as I would love to have a magical spreadsheet that uses logic and real world math, we are talking about the universe of GT6. Normal laws don't apply even using their math.:lol:

Example
image.jpeg


The numbers in the yellow cells (red numbers) all need to be manually entered from what the game and MoTeC tells you. This gives you a base for figuring out the real world formula, but implementing MoTeC data.

image.jpeg

Using those numbers I can create a sheet/graph that tells me what the RPMs will drop to when I shift kind of like your chart (automatic transmission). The first 2 are true from MoTeC data and the others (setups) are using that data plugged into real world formulas.

They get close, but when it comes to fine tuning the numbers....
image.jpeg

They don't match (real world math vs. MoTeC). I am trying to get all of the RPM drops at upshift located between 5,400-5,700 on a nice incline, but it has me dancing around instead. That's why I'm hesitant to believe, yet hopeful, that there is a formula you can use that will work for every car, every time.
That is one of the nice things about this guide. You can go way down into the nitty gritty of transmission tuning (the things way over my head) and get a good feel for the gears/car or just follow the step by step instructions for quick tuning.
 
Ironically for how bad the Dyno screen is, the gear line screen is very very accurate for the length of each shift. It's just figuring out what the length actually means for RPM drops
 
Ironically for how bad the Dyno screen is, the gear line screen is very very accurate for the length of each shift. It's just figuring out what the length actually means for RPM drops
And that is something else I am wanting to learn a little more about using your guide...the infamous dyno bar!:scared:
 
I'll have to give those numbers a go and see what it does to us auto users. As much as I would love to have a magical spreadsheet that uses logic and real world math, we are talking about the universe of GT6. Normal laws don't apply even using their math.:lol:

IMG_20151126_202510.jpg

They don't match (real world math vs. MoTeC). I am trying to get all of the RPM drops at upshift located between 5,400-5,700 on a nice incline, but it has me dancing around instead. That's why I'm hesitant to believe, yet hopeful, that there is a formula you can use that will work for every car, every time.
That is one of the nice things about this guide. You can go way down into the nitty gritty of transmission tuning (the things way over my head) and get a good feel for the gears/car or just follow the step by step instructions for quick tuning.
Your sheet misses drop counter, I'm making own decisions where I want rpm to stay and then doing gears what makes it stay there, when using above sheet I change "redline/shiftpoint" per gear to see where it goes and adjust it to proper.
Magically real world schemas theories are working on GT6.
 
Potato-Potatoe situation. You are using the RPM drop for your calculations, and I'm using the dropped RPMs to see where the RPMs pick up in the next gear. It's the same as Mr. P's calculation sheet that I've been using as well....

image.jpeg


Many ways to get to the same numbers...just doesn't match what you expect when you go to MoTeC.👍

Edit:
It's close I'll give it that.
 
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And that is something else I am wanting to learn a little more about using your guide...the infamous dyno bar!:scared:
Yeah well I thought I had it figured out then you found a loop hole large enough to drive a Bugatti through so gonna have to dig a little deeper. I think the Duno screen is compressed and dynamic so getting it figured out is going to be tuff.
 
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