Competition gearboxes
At Rodiauto Sport you will find gearboxes and internal components prepared for competition: dog boxes, sequential gearboxes, close-ratio gear sets and short final drives for the PSA (MA and BE), Renault (JC) and VAG groups. If you are not sure what the difference is between each option, here we explain it so you can choose what your car really needs for its use: tarmac, gravel, track or rallycross.
| Dog boxes |
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They replace the original synchromesh with straight-cut gears with "dogs" (engagement teeth, from the French word crabot). The shift happens by direct mechanical engagement between gears, not by cone friction, allowing much faster shifts with no synchro wear. In return they are noisier and require a more precise driving technique. They are the foundation of any serious competition build.
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| Sequential gearboxes |
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The gear selector works by means of a rotating drum: each movement of the lever (up/down) shifts up or down one gear, in order, without skipping positions or passing through neutral by mistake. It is the typical rally and track system because it drastically reduces shift time and the risk of selecting the wrong gear under pressure.
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| Close-ratio gear sets |
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The set of internal gears for each speed (1st to 5th/6th) designed with smaller steps between them than in a street gearbox. The engine stays longer in its useful torque and power band on each shift instead of "dropping" revs. Ideal for track use and highly tuned engines that only perform in a narrow RPM range.
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| Short final drives |
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It is the final ratio between the pinion and the ring gear (the "differential"). A short final drive has more teeth on the ring gear relative to the pinion, which multiplies acceleration in each gear at the cost of a lower top speed. It is used in rallycross, hill climb, gravel and short circuits where launching out of corners matters more than top speed on the straight.
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| Not sure which final drive or ratio suits you? Before buying, calculate the real speed your car will reach in each gear based on the final drive, ratio and tires you fit. |
Open speed calculator |
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Gearboxes by manufacturer group
We organize the catalog by gearbox family so you can find parts compatible with your vehicle: PSA MA GEARBOX, PSA BE GEARBOX, RENAULT JC GEARBOX and VAG GROUP GEARBOXES.
DescriptionFrequently asked questions
We work with specialist competition gearbox builders for the PSA MA, PSA BE, Renault JC and VAG groups. All the parts we offer (dog rings, close-ratio sets, short final drives, sequential gearboxes and reinforcements) are designed for competition use: rally, rallycross, track and hill climb. If you are unsure which combination of ratio and final drive is right for your engine and discipline, contact us and we will advise you before you buy.
Does a dog box need the clutch for every shift?
It depends on the design. Conventional dog boxes still use the clutch, although the shift is faster and more direct than with synchromesh. Competition sequential gearboxes usually allow clutchless upshifts.
Can I fit a short final drive without changing the whole gearbox?
For most of the PSA, Renault and VAG groups we work with, yes: the final drive (pinion and ring gear) can be replaced independently of the internal gear ratios.
How do I know which close-ratio set suits me?
It depends on your engine's torque curve and the circuit or stage where you compete. Use our speed calculator to simulate the speed in each gear before deciding, or contact us and we will help you choose.
Are sequential gearboxes compatible with my original engine block?
Compatibility depends on the group (MA, BE, JC, VAG) and the bell housing. Check each product page or write to us with your model and engine to confirm.
