Gear ratios should be chosen so the engine stays in its powerband through every corner exit on the track, with the top gear just long enough to avoid hitting the limiter on the longest straight. Get that right and gearing mostly disappears as a concern; get it wrong and you’re either short-shifting out of the power or bouncing off the rev limiter before the braking zone.
What you’re actually optimizing
Every gear covers a range of speeds where the engine stays near its power peak. Closer ratios keep the engine in that range more precisely after every shift, which helps acceleration, but require more shifts per lap. Wider ratios mean fewer shifts but larger drops in engine speed after each one, which can drop you out of the powerband, especially exiting slow corners.
Start from the track, not the gearbox
- Identify your slowest corner. This sets the lower gears, since you need enough gear range to accelerate cleanly from that speed without bogging down or immediately hitting the rev limiter.
- Identify your longest straight. This sets top gear. You want to be just below the rev limiter at the end of that straight, not well below it, since a top gear that’s too short wastes top speed, and one that’s too long means you’re never using the engine’s full range.
- Fill in the middle gears to space shift points evenly. Once the top and bottom are set, the goal is even, predictable drops in engine speed at each shift so you’re never caught in an awkward spot between gears mid-corner-exit.
Final drive vs. individual gear ratios
Final drive multiplies every gear ratio at once, effectively shifting the whole gearbox shorter or taller in one move. It’s often the fastest way to make a broad correction, too short everywhere or too tall everywhere, before fine-tuning individual gears for specific corners.
The bigger picture
Gearing doesn’t change how the car handles through a corner, but it changes how effectively you can use the power you have on exit, which interacts with the differential and mechanical grip in that same phase. A gearing mismatch can look like a traction problem even when the setup underneath it is fine. See Learn Setup Engineering for how gearing fits alongside the rest of your setup tools, and how onRails separates gearing issues from true handling issues when diagnosing exit-phase problems.
Related questions
Should I run the shortest gearing possible for the best acceleration?
No. Gearing too short means hitting the rev limiter before the end of straights, which wastes top speed you could otherwise be using. The goal is matching gearing to the track, not maximizing acceleration in isolation.
Why does my car feel like it has no traction out of one specific corner?
Check gearing before assuming it’s a mechanical or differential problem. If that gear puts the engine below its powerband right at corner exit, the car will feel sluggish even with a perfectly good setup underneath it.
Does final drive or individual gear ratios matter more?
Final drive is the faster, broader adjustment for a gearbox that’s generally too short or too tall everywhere. Individual gear ratios matter more once the overall range is right and you’re fine-tuning specific corners or shift points.