Transmission settings help

  • Thread starter rokkon
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rokkon

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While I've been playing GT games since the first one on PSOne, I never really got into personally tuning my own cars' settings. I usually just ended up using racing or other preconfigured settings and ran with it. But now that GT4 is out, I really want to learn the art of tuning.

I have a pretty good idea of how suspension tuning works, as my grasp of physics in that area is decent, however I'm lost on transmissions. Generally, I'm lost on how things like hp, torque, and revs are affected by gear ratios.

Right now I'm trying to figure out settings for a Mini Cooper S. I did some mild engine upgrades (hp up to around 180 from 163) and now the engine revs never drop below 5's after gear 2 when upshifting. Is this normal?
 
invest in a triple plate clutch ,( unless of course you are using auto trans) and a racing flywheel . If you have a custom gear box use the auto setting to increase top speed by lowering the gear ratio ( slide right to lower ) just be carefull not to go too far to the right without a major increase in horsepower.
 
The higher the number for the gear, the more acceleration, but less top speed. That's why 1st gear might have a number from around 4-7 while 6th gear has a number around 1. On twisty tracks make the gears tuned for acceleration because you'll never reach high speeds. On an oval course tune it for high speed.
 
Trying going over the test track to get an idea of how you are doing. Do the 400m and/or 1000m once with changing the settings, then go from there to see if you can make you're times faster. Do some experiments with different settings and ratios, and look at the effect that has on how fast you accelerate, and what speed you have to shift at.

In the gt3 part of this site, I made a thread asking, "What exactly is final gear?", and people made some really helpful responses about gears and ratios, so try checking that out.
 
Ahh, after some informative reading (and bookmarking for later digestion), I've learned a lot of stuff I didn't know. I should've checked the GT3 section, I don't know why I didn't think of that earlier. Thanks again everybody...I'm one step closer to tuning the perfect settings for me. :)
 
I have been playing Gran Turismo since the begining. One thing I have found out is that I have been using the same transmission setups from the begining. I started out by using the same ratios as the older GM 4 speed trannies used and adapted them from there on. Below is a 6 speed tranny setup that always seems to keep the engines in the power bands. The only thing I ever change is the final drive depending on how much top end you need on a giving track.

1st = 2.65
2nd = 1.94
3rd = 1.34
4th = 1.00
5th = 0.832
6th = 0.695
Final = 4.100 (usually 150-170 depending on rpm motor will turn)
Use less than 4.100 for more top speed and more for less top speed but killer acceleration.
By no means I am claiming them to be perfect, but they have never let me down except in GT1 when the stage 4 turbo on a few 4cyl engines was extremely bad and then it would not keep them in the power band.
 
Here is my gearbox method (don't remember where I found it, but it works)

- take a short autoset (the 3th or 4th from the left)

-1st and 2nd: as long as possible (glider completely to the left)
-3th: in the middle of 2nd and 4th
- 4th and 5th: as short as possible (glider completely to the right)
- 6th: don't touch
- don't change autoset, but adjust final to the track.

If you read French, have a look at my website, which contains an elaborate setup guide with a calculator to adjust final to each GT3 track (We in Europe don't have GT4 yet):

http://perso.wanadoo.fr/plmgt
 
Here's what works for me:

Get a fully custumizable gearbox and set it up like this:
- Shorten top gear (usualy 6th) to the max
- Set up 1st and 2nd gears to the longest setting
- Adjust 3rd, 4th an 5th to keep the gaps progressively smaller (after you finish you can fine-tune according to your needs in certain corners)
- Set up the final gear to leave the car 500 or 750rpm bellow red line on the longest straight (you will need aditional revs for slip-streaming). To do this you will need to set-up, test and set-up final gear again until it's right.


This way you will get:
1 - Closest gearing possible with the best acceleration, for a certain top speed
2 - You only do it once. When you need to change the setup, just change the final gear to match the top speed you need on one track (don't forget to leave some additional rpm available for slip-streaming).

This saves me a lot of set-up time...
 
Why would you make 1st and 2nd longer? That isn't the best way to do it! You are just making your accl. worse. If you want to get off the line quicker make the gears shorter (make the numbers higher, not lower) . If you want top speed go to the left.
You will lose some thing else when you do something usually.
 
Unless you are drag racing, you don't need short 1st and 2nd. If your road racing, longer 1st and 2nd means that they can actualy be used in the race instead of only for the start.

Also allows you to have the remaining gears closer, and allways on the power band.

Try it...
 
The first 2 or 3 gears should be rather tall since, on most tracks, you won't use them much ...

With 4th, 5th, and 6th gear, you should maximize the power ...

With a power curve like this ...
0408it_ppwrx03_z.jpg


You'd want to be somewhere between 6300 and 7700 RPM at all times since that's where you make the most power ... So, for the higher gears, you'd want to shift at about 7700 RPM and then end up at 6300 RPM ... So if 4th gear is 1.200, you'd want 5th gear to be ... 1.2*6300/7700 = 0.982

With a power curve like this ...
0411it_ppcivic_02_z.jpg


You'd want to keep revs as high as possible as peak power is between 6000-7000 RPM ... So for the higher gears, tuning the transmission so you drop slightly below 6000 RPM on an upshift would be ideal ... So, if 4th gear is 1.2, you'd want 5th gear to be ... 1.2*5900/7000 = 1.011

With the older Muscle cars, you won't want to shift anywhere near redline since they often make the most power between 4000-5000 RPM ...

Usually, you don't want to change your gear ratios from track to track unless it's awkward going through corners and/or coming out of corners ... Generally, the only thing you want to change track to track is the final drive ratio to adjust your top speed ... At the end of the longest straight, you want to be very close to hitting the rev limiter in top gear ... I'm never in 2nd, so I don't need to save a few extra RPM for drafting, but if you want to be safe, then do so ...

In drag racing, you want to keep power in all gears maximized, not just the 3 top gears ...
 
MaxxTraxx
Why would you make 1st and 2nd longer? That isn't the best way to do it! You are just making your accl. worse. If you want to get off the line quicker make the gears shorter (make the numbers higher, not lower) . If you want top speed go to the left.
You will lose some thing else when you do something usually.
Click to expand...


We are several on this post to advice the same thing: long 1st and 2nd. I did some extensive testing for it in GT3. And my conclusion is that on 400 and 1000m acceleration, a long 1st and 2nd and a short 4th and 5th (with the correct final value) gives faster accelerations than the standard GT gearbox setup (with the same final value).

If you want to see the test results (application of Sukerkin and Numbone's A1K method), have a look at the following page of my website: http://perso.wanadoo.fr/plmgt/boite.htm

The page is in French, but section 4.8 give the tables with the test results.

And thanks to Jmac for his very interisting technical comments
 
Well... I guess in theory the same principle would aply to drag racing (keep the gears as close as possible), but shorten the final gear to use as many gears as possible in an optimized power band.

But in reality, you have to consider that shifting many times will add time to the drag, and there will be traction control problems with very short first gears.

So you would have to try to get the "right" first gear (optimizing traction/acceleration), and then set-up the next ones to keep the engine on the best rev range. Always somewhere between max torque rev and max power rev. In the first graph example between 6000 and 7500, and on the second between 6000 and 6500.

In my opinion anyway... But I wouldn't be the best one to help... I like the whole driving thing. With corners, braking and stuff :)
 
In the 1/4 mile, you probably wouldn't want to use all the gears because, as stated above, shifting takes time ... It takes about 0.5 seconds (for the average human) to shift, which is a friggin' eternity in the 1/4 mile ... So, to get optimal results, you'd have to balance the amount of gears based on the width of the powerband ... For a wide powerband engine, you can get away with very few gears whereas with a narrow powerband, you're forced to use most/all of the gears to get optimum times ...
 
It is an interesting thread, and for the most part, you seem to have it figured out. There is one other area that you can look at for 'fine tuning'. That is after driving some laps, see if there's anywhere you're 'in between gears', like having to shift in the middle of a corner, or right on the exit. In the stock or street cars, the slow gear changes kill your exit speed.

For the full race transmissions, clicking the individual gear a few clicks longer will probably help there - but be aware it may hurt you somewhere else.

I agree - for road racing - that you need the tallest first gear possible, and sixth should top out with the light blinking but not on the revlimiter. Stagger the set in between those two points, but remember to make the gaps smaller as you go higher in the gears. As wind resistance picks up, a large drop in revs or starting to go up hill, could actually slow you down.

Also a not for ovals. Try to set 4th, 5th and 6th very close together. Fifth is the gear you want to run in, sixth is for the draft and fourth should be for the tighter of the two corners on the oval.
 

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