A close-ratio gearbox has small gaps between gears. Shift up and the engine RPM drops less. That is useful when the engine has a narrow power band and needs to stay high in the revs to work properly.
A wide-ratio gearbox has bigger gaps. Shift up and the engine drops further. That can suit engines with broad torque, road cars that need flexibility and vehicles that cover a wide speed range without constant shifting.
How to measure “close”
Close and wide are not official categories. They are descriptions, and gearbox sellers use them generously. Two numbers tell you what you are actually looking at.
The first is the step between gears. Divide the next ratio by the current one and multiply by your shift RPM. That is where the engine lands after the shift. A step of 0.80 from 7,000 rpm lands at 5,600. A step of 0.60 lands at 4,200. That 1,400 rpm is the difference between a car that keeps pulling and one that pauses to think about it.
The second is the spread: first gear divided by top gear. It tells you how much speed range the whole box covers. A box with a small spread has to squeeze its gears close together because it has less range to share out. A box with a big spread can have a low first and a tall top, but the gaps in between get wider unless you add more gears.
A worked example
Here are two example five-speeds (illustrative ratios, not a specific named gearbox) on the same 4.10 final drive, a 205/55R16 tyre and a 7,000 rpm shift point.
- Close example: 3.00, 2.10, 1.60, 1.27, 1.00. Spread 3.0.
- Wide example: 3.50, 2.05, 1.35, 1.00, 0.80. Spread about 4.4.
| Gearbox | 1st to 2nd lands at | 2nd to 3rd lands at | 1st at 7,000 | RPM at 70 mph in top |
|---|---|---|---|---|
| Close | about 4,900 | about 5,330 | 68 km/h | about 3,880 |
| Wide | about 4,100 | about 4,610 | 58 km/h | about 3,100 |
The close box keeps the engine roughly 700 to 800 rpm higher after the first two shifts. On a peaky engine, that is the whole point. But look at the other columns. First gear is taller, so pulling away needs more clutch. Top gear is a straight 1.00, so the motorway costs nearly 3,900 rpm. Close-ratio boxes often end up with a shorter diff to fix the tall first gear, which makes the cruise even busier. Nothing is free. The spread has to come from somewhere.
Track
For track use, close ratios are often the answer. The car spends its life in a small speed window, and the goal is to keep the engine pulling after each shift. A naturally aspirated engine that makes its best power near the top wants the next gear to land close enough that it stays alive. If the revs drop too far, you lose time waiting for the engine to climb back into the good bit.
On a circuit the tall first gear barely matters, because you only use it in the pit lane. What matters is which gears cover the slowest corner and the end of the longest straight, and whether the shifts in between land in the power.
Road
For road use, close ratios can become tiring. You may find yourself changing gear constantly, sitting at higher revs and wishing top gear had more leg. A medium or wide-ratio road gearbox usually makes more sense because the engine can pull from lower RPM and cruising matters.
Most factory road gearboxes are also progressive: the gaps shrink as you go up. The wide example above does exactly that, with its steps going from 0.59 to 0.66 to 0.74 to 0.80. Big gaps low down, where the engine gets through the revs quickly anyway. Smaller gaps higher up, where wind resistance means every lost rev costs more.
Drift, off-road and touring
For drift, the answer is not automatically close ratio. A drift car often needs to hold one gear through a corner and manage wheel speed with throttle. The right final drive can matter more than having tightly stacked ratios. You want the gear that works for the track layout, tyre size and power level.
For off-road, close ratios are usually the wrong conversation. Low range, crawl ratio and control matter. A gearbox that is exciting on a circuit may be useless when you need to move at walking pace without burning the clutch.
For touring, wide ratios and overdrive are your friends. Long-distance cars want low noise, low cruise RPM and easy progress. The best touring gearbox lets the engine pull cleanly without making the driver work for every small change in speed.
Close ratio is a tool, not a grade
The trap is treating close ratio as a synonym for performance. A close-ratio gearbox in the wrong car can feel frantic and annoying. A wide-ratio gearbox in the right car can feel effortless and quick.
A torquey engine with a flat curve barely notices a 0.60 step, because it makes much the same torque at 4,200 rpm as it does at 5,600. Give it a close box and you get more shifting for almost no gain. A high-strung engine that only works above 5,500 needs every one of those saved revs. The engine decides how close is close enough. If you are fitting taller or shorter tyres at the same time, remember they move every road speed but leave the steps between gears untouched.
Run the numbers
Look at the RPM drop between gears and the road speed in each gear. BoxSelector shows both for any ratio set, diff and tyre, which beats squinting at a seller’s description. Then match the gearbox to the engine and the actual driving, not the badge on the side of the casing.