Transmission tunes per track, my guide

Dom Sireci · Feb 1, 2015

The system I use to tune the transmission for each track is different than most people. It's a trial and error method, that's rewarding in that it's never failed me in getting the fastest times. It is time consuming, but no more so than the method I see most use. With practice, it does get easier to use too!
First I take the car to the track. I look at the length of the longest straight. Then I take a guess at what I think the fastest speed will be. As an example, I took the '87 Motul Civic Si to Circuito de Madrid. The longest straight on that is .51 miles.
Next I take a guess at what I think the top speed will be. In the case of my example, that was 193, and I adjust the top speed accordingly. Keeping track of the race tracks you've run the car at by noting them in the settings comments, helps tremendously.
If the last race track had a straight of .49 miles, for example, you know you're not far off the mark you need. In fact, being that close, I'd try running the car on that setting. Sometimes you can get away with not doing any transmission adjustments.
Moving on, after I've adjusted my top speed, then I go to the final drive. My goal here is to adjust it so that my top gear is 1.000, a direct drive. This is, I think, the ideal place for a top gear.
So, in my example the top gear is at .904, so I need to shorten that. So I know I need to move my final drive selector to the left. Here again, I'm guessing. I move it over to 3.55.
Then I go to my top speed auto set, move it off 193 then back again and this changes your transmission gearing.
In this example, it put my top gear ratio at .922.
So I know I have more adjusting to do.
I move the final drive down to 3.25. Go up to the max speed auto set and move off 193 again, then back to it. Now my top gear ratio is 1.007, too short.
So, now I have to move the final drive selector to the right.
Using my method, I guessed 3.27, and got a top gear of 1.001. Good, I'm very close now!
I like my tranny on the short end of direct drive, so now I'll adjust the final drive .001 at a time, and go move the auto select each time, until I get that magic 1.000.
Of course, this was wrong. So I had to go back and shorten the gearing further. On the track, I run the car down the straight. I want it to run to the braking point so I see the red light come on signaling redline. Then I bump the top speed up one notch, and adjust the final drive accordingly.
For those curious, I ended up tuning this transmission to this race track to, 149 for a top speed, and a final drive of 4.227. In a race, if I find that to be still to short because of drafting, (rarely does this happen) I adjust the final drive only. Usually moving it to the left .500 is enough of a difference. Once, I had to move it 1.000 over.
And that's it! You don't have to be as precise in your adjustments, .999 or 1.001 probably won't make that much of a difference.
Please let me know what you think!

HBR-Roadhog · Feb 1, 2015

Dom Sireci
First I take the car to the track. I look at the length of the longest straight. Then I take a guess at what I think the fastest speed will be. As an example, I took the '87 Motul Civic Si to Circuito de Madrid. The longest straight on that is .51 miles.

If the last race track had a straight of .49 miles, for example, you know you're not far off the mark you need. In fact, being that close, I'd try running the car on that setting. Sometimes you can get away with not doing any transmission adjustments.

Actually you could be way off the mark. The length of the straight is just one factor in how much speed you can get on that straight the other factors are entry speed , braking distance and elevation change. For example you could go quite a bit faster on a .49 straight that has a high speed corner at both ends than you could a .51 straight that has a hairpin at each end. Faster still if the short straight is downhill and the other uphill.

There is also a lot more to it than adjusting the top gear to the speed you want to attain. This always depends on the track but each gear is important. Ideally you want your gearing set in such a way that you always have a good gear for every corner where you can get in and out without over revving or bogging down to try and attain max acceleration out of every corner. In some cases you may even want to set the top gear a little lower than the car can attain simply for the better acceleration everywhere else. In other cases you may want to set the top gear to a speed that can not be attained simply because the way the power curve works you may be able to attain more speed with a higher gear even though you do not reach the top speed set.

Dom Sireci · Feb 1, 2015

HBR-Roadhog
Actually you could be way off the mark. The length of the straight is just one factor in how much speed you can get on that straight the other factors are entry speed , braking distance and elevation change. For example you could go quite a bit faster on a .49 straight that has a high speed corner at both ends than you could a .51 straight that has a hairpin at each end. Faster still if the short straight is downhill and the other uphill.

There is also a lot more to it than adjusting the top gear to the speed you want to attain. This always depends on the track but each gear is important. Ideally you want your gearing set in such a way that you always have a good gear for every corner where you can get in and out without over revving or bogging down to try and attain max acceleration out of every corner. In some cases you may even want to set the top gear a little lower than the car can attain simply for the better acceleration everywhere else. In other cases you may want to set the top gear to a speed that can not be attained simply because the way the power curve works you may be able to attain more speed with a higher gear even though you do not reach the top speed set.

HBR-Roadhouse, I only meant that the previous settings can sometimes be the same settings. You're right though, all the factors you named make a difference. As for the short top speed to gain acceleration times or a longer one than attainable for a higher top end. This is always a balancing act. One has to usually choose what works best for them. Under usual circumstances however, I've found my system to balance that line pretty well.

HBR-Roadhog · Feb 1, 2015

Also note that the red light does not signal red line. It is a shift indicator and is saying it is time to shift to the next gear. Depending on the car some still have a ways before the rev limiter is hit and some preform very well when revving past the shift indicator.

Personally I have not found any generic system that does a very good job with trans tuning. Different cars behave differently, different tracks have different requirements and different still for different cars. About the only thing I can think of for generic tuning is just to drag the the speed to about what you think you can get and then drive it and make adjustments as needed.

Would be nice if GT were more like Forza in the tuning part, 3 big advantages in Forza over GT are.
1: Ability to pause during a test drive and alter the tuning settings then resume.
2: Ability to pull up a real time telemetry while driving to see where your power and torque are at as well as contact patch, temps and such
3: Ability to save the settings to a file of your choosing making it easy to load back to the car later and have an almost unlimited number of tunes per car.

Fanapryde · Feb 1, 2015

HBR-Roadhog
1: Ability to pause during a test drive and alter the tuning settings then resume.
2: Ability to pull up a real time telemetry while driving to see where your power and torque are at as well as contact patch, temps and such
3: Ability to save the settings to a file of your choosing making it easy to load back to the car later and have an almost unlimited number of tunes per car.

^^^
I would really like to see these tools in GT6, #1 to begin with...

Dom Sireci · Feb 2, 2015

As for Forza... Those are nice features, and I hope to see them in GT7. That said, I've played Forza 5, and as far as I'm concerned they left one thing out of the game which I consider unforgivable. The ability to completely customize your controller to your liking.
As for the red light, true, it isn't a red line marker, but I use it as a marker none the less. For better or worse. Using a system isn't all that bad, I think. It's a faster way of getting a general tune for a track, that's all...

ALB123 · Feb 2, 2015

Dom Sireci
As for Forza... Those are nice features, and I hope to see them in GT7. That said, I've played Forza 5, and as far as I'm concerned they left one thing out of the game which I consider unforgivable. The ability to completely customize your controller to your liking.
As for the red light, true, it isn't a red line marker, but I use it as a marker none the less. For better or worse. Using a system isn't all that bad, I think. It's a faster way of getting a general tune for a track, that's all...

If you're getting positive results, that's all that really matters. If you like setting up transmissions this way and you're not running out of revs on straights, or stuck in between gears on turns, you're probably doing something right - at least for you. I'm terrible at tuning, so I can't really say if I like your system or not, but I appreciate you sharing your method. 👍

Dom Sireci · Feb 2, 2015

ALB123
If you're getting positive results, that's all that really matters. If you like setting up transmissions this way and you're not running out of revs on straights, or stuck in between gears on turns, you're probably doing something right - at least for you. I'm terrible at tuning, so I can't really say if I like your system or not, but I appreciate you sharing your method. 👍

Thank you, ALB123! That really is the point, you know. I had this system, which I've been using for a long time. I didn't see anyone else using it, so I thought I'd post it as an alternative to the more common system that I see.
Completely off subject, I see under your post this quote, "Ashes and diamonds, foe and friend, we are all equal in the end". Two Suns in the Sunset from The Final Cut. Nice.

ALB123 · Feb 2, 2015

Dom Sireci
Completely off subject, I see under your post this quote, "Ashes and diamonds, foe and friend, we are all equal in the end". Two Suns in the Sunset from The Final Cut. Nice.

Yes, sir!!

👍

Dom Sireci · Feb 2, 2015

Nice to meet a fellow Floyd head, here of all places!

TonyJZX · Feb 2, 2015

way too complicated for something that should be easy

if the car pings the redline at the end of the longest straight in the game, you're done

Dom Sireci · Feb 3, 2015

I agree with you Tony. However, I want to be able to do that and get the fastest acceleration I can too. HBR-ROADHOG was talking about changing the individual gears to alleviate dead spots in corners, that is too high or too low rpms in the gear. I do run into dead spots, so to speak. I'm with you though, to change the gear for a corner is complicated, and probably leads to other dead spots in other corners.

NixxxoN · Feb 3, 2015

I give you an easier one:

1) Go to the longest straight of each track
2) Test the top speed
3) Put 10 km/h more than the max speed you got (because of slipstreams and some additional margin)
4) Done

Also I recommend to set the 1st and 2nd gears long enough so your car doesnt get much wheelspin.