Personally I avoid messing with the individual ratios whenever possible.
That's how I do it. Hope that helps. 👍
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When dealing with standard production car transmissions this is an easy way to adapt a car to specific tracks or situations, but it's not entirely accurate.
The race transmission is not the OEM trans, it's a "race" transmission, ie. a TKO, Richmond or other type transmission specifically designed for racing. Judging by the numbers 90% of the cars use, it's a bastardized TKO or T-56 setup with a fairly standard gear set. It's also a standard trans, not an automatic, even though how it's shifted is is somewhat irrelevant as far as the game is concerned.
Most Auto's are 3 or 4 speeds, or 3+OD or 4+OD. Manuel's trans is 4, 5 or 6 speed, some specialty units can be 7 or 8 gears.
IF you're using the stock trans for the car, than adjusting final drive makes logical sense to make the trans taller or shorter to fit the track, and it works out into a decent little package.
HOWEVER... If you use the race trans, it's a generic setup that has nothing at all to do with the car. There's a reason they offer so many different gear combinations with a TKO or T-56 for example. Each car is unique. The same car at each class break is unique. Every speed part or weight change effects the power band AND the torque curve. How T-10 handled the torque vs hp in a car can make a world of difference in what you set those individual gears at.
As an example, here's a few gear sets for the Tremec T-56:
-SET 1- // -SET 2-
1-2.97 // 1-2.66
2-2.07 // 2-1.78
3-1.43 // 3-1.30
4-1.00 // 4-1.00
5-0.80 // 5-0.74
6-0.62 // 6-0.50
The first set is much more aggressive with shorter gears overall, meaning it will accelerate quickly but will have a lower top speed. The 2nd set will come off the line slower but will achieve a higher speed.
There's another 13 different sets for that trans alone, and that's just one part number for one type of aftermarket transmission.
All that said, T-10 did us a favor by using the same start point, or same gear set for most of the race transmissions within the game for production type cars. (Race cars are a different animal, though the same general rules will apply)
There are a few BASIC rules of thumb for playing with individual gears that will keep you on track to figuring it all out. I use these because we're all different, as is each car and each situation. There is no "perfect" tune or "perfect" plug in set of numbers that fits everyone. This is a bit long winded, but if want to know, read on...
Before you even start, when you build your car make a note of the HP and Torque graphs and the max of each before you go to tune the trans. You NEED to know when your car is making power and when it isn't.
This isn't the exact "definitions" of the two, they're more like concepts to help you understand the end result. I won't debate the accuracy of the definitions, it's not the point. It's having you understand what the gear change is going to do that's important.
The way I think of these two things goes sorta like this...
Well, a lot like this, actually.
HP = Speed. It's how fast you can go.
TORQUE= Power. It's the force that get's you to the speed hp provides.
All TORQUE = Pulling your house off it's foundations... very slowly.
All HP = Spinning half your lawn all over your house while it laughs at your foolish attempt to move it anywhere.
You need TORQUE (TQ) to get going, you need HP to keep you going. HP is a capacity, TQ is a force.
The gears in the transmission work with TQ, and the multiplying of it to provide the power or force to move the car. It's the bridge from dead stop to all the speed that HP can provide. This is a critical point to understand. You can cut the capacity of HP off by not applying the TQ correctly. In other words, you can limit or handicap your car by not allowing it to use all it's got.
This is the where, what and why of the transmission and the gears, and why just using whatever numbers they throw at you can hurt you and your car's performance because the gears used are not set to the car, but to the transmission itself.
When you started out, most likely you started to throw numbers around and move sliders over and over again trying to figure out what the transmission was doing. Sometimes you hit on something, so you try it in the next car, but it falls flat on it's face.
What I needed when I started out were a few simple rules and concepts to keep in mind, things that would keep me pointed in the right direction and allow me to make "educated guesses" instead of arbitrary slider moves.
Hopefully these will help you get started in black arts of gear selection and allow you to first survive, and then excel in making the race trans work well and allow you to fully take advantage of you car's potential.
Basic gear rules:
#1: Big # = SHORT gear, Small # = TALL gear.
#2: SHORT gears = acceleration, Tall gears = speed
#3: Gears that are too SHORT prevent a car from stretching it's legs, and can cause severe over steer issues on throttle exit. I can't tell you how many times I've seen people work setups over and over again only to find they had too short a gear in the car for the corner and were simply overpowering the exit.
#4 Gears that are too tall will not accelerate well. They will make a car feel sluggish, lethargic. They will draft like a mother though...
#5: Tall gears in 1st/2nd can cause excessive wheel spin, especially if using a Short final drive gear. Conversely, though a shorter gear will cause wheel spin, it will reach it's shift point quicker, which takes it out of the equation. Better to spin a little and get moving into 2nd/3rd than it is to sit and spin in 1st...
#6: The final drive is NOT the final word an how fast a car goes.
Putting the theory into practice...
I'd recommend finding a car you really like, and drive A LOT. Start in the C class. Build the car around two things: Transmission and Tires. Try to leave all chassis and HP related upgrades out of the picture. Next, pick Race or Drag, as each type of trans setup is totally different. Drag is simple enough, and is even easier once you can tune for a road course, so I'd recommend you start with race as opposed to straight line.
Start with the trans out of the box, run at least ten laps, preferably with Manuel's trans. If you use a clutch, fine, but it's not necessary for what you want to see, and may even get in the way of the result unless you are very proficient with it.
Pay close attention to the shift points, where they occur, what RPM range, what part of the track etc. Maple Vally short in the C class Rival challenge is an excellent place to do this as it's short, the cars are basically stock, and if you keep track of the leader board you can make some cash while you're learning...
After this, go into the settings and look at the gears. You only use first to get off the line, so if you can slide it up or down to either create or take up space to better use the other gears, do so. I will usually make it slightly taller to put 2nd and 3rd into better positions in the RPM band.
On most tracks, 2nd/3rd and 4th are the $$ gears. You want to build the gear set around NOT having to shift. Of course you will have to, but the point is to eliminate all unnecessary shifts, especially any shifts that occur in the middle of corners. You are going to be adjusting the individual gears to work with specific corners, allowing you to maintain stability, momentum and eliminate the time wasted having to shift.
This may mean a shorter 2nd and a longer 3rd, or a longer 2nd and a shorter 3rd. My traditional set up will usually make 2nd and 3rd taller so I can stay in one gear on any track with mid speed corners. I'll make 4th just a bit taller to eliminate the need to up shift in that one section that always seems to pop up in any decent sized track. I find it's quicker to hang in 4th on the limiter than it is to shift up then shift back down. Not only for time, but also because it holds the car steady. It's one weight transfer instead of three...
I then go about adapting 5th and 6th to take advantage of any speed portions of a course, making 5th the primary and 6th the overdrive to get that last ounce out of that other single section that seems to pop up in every track over a mile and a half.
A perfect place to try this out are the esses at Suzuka. I set my car up to take them in one gear, in the power band. If I did it right, I don't have to brake or shift at all, and can sail through them smooth as silk. Every shift costs you time, both in the actual shift and in the engine recovering it's momentum building RPMs.
Just as a side note...: One thing about the T-10 set up is the penchant for 5th to be the 1:1 gear. IRL, it's usually 4th, with 5th and 6th being overdrives. In Race specific cars, you may not even see a 1:1 gear. In addition, the 3:30 final gear is an arbitrary gear. Typical grandma grocery getters would have something akin to a 2:73 final gear, a "highway" or "cruising" gear. Drag cars run 4:11's, 4:56's and shorter by comparison, as they need the acceleration, not the speed.
As you progress, you'll find yourself looking at tracks in sections, and tuning each gear to a specific point.
In the end, it's all timing. The perfect trans set up is the one has you in the power band all the time, shifting as little as possible and shifting at the best opportunities.
As for the final gear... You should be redlining just at the braking point at the end of the longest straightaway or fastest course section. If you hit the rev limiter, you're too short. If you have 1,000 RPM left, you're too long... UNLESS drafting plays a part in the race you are in. Anytime drafting is a possibility, always leave 500-1K RPM headroom to take full advantage of the draft. The danger is trying to balance how much room you leave vs how much top speed you lose without the draft. You can't have both... I myself usually end up too tall, which means one mistake and I'm done, as I don't have the speed without the draft to stay with the pack. This is because I tend to be a bit cautious and conservative. It's better to be banging the limiter in the draft than it is to have room left at the top. At least you have a fighting chance to catch up should you get wrecked or spin or what have you.
Typical final (rear end pumpkin) gears run from mid 2's all the way up to mid fives. Some common rear end gears for the Ford 9", one of the most universally used rear ends in the custom and racing world are 3:23, 3:40, 3:55, 3:73, 3:90, 4:10 (4:11), 4:30, 4:56. Some Mopar rear ends used 4:88s to 5:86's...! In the aftermarket world, there are a ton of custom gear sets for just about anything you can think of.
I find myself in the 3:23 to 3:55 range for many road course setups. One thing I can tell you is that I always set this gear last. I always start with a 3:23 or 3:55 depending on the HP and TQ of the car. Once I have a decent set of gears, I use the final gear to adjust to individual tracks. Shorter tracks = Shorter gear. The nice thing about this is that your timing stays pretty consistent with the car. You may tweak a gear or two every once in awhile, but once you get a car where you really like the shift timing, you'll find yourself not wanting to change it if you can help it...
I wish you great success, and stay off the wall..!
