Paddle shift ↓
Closed loop - what is it, and why is it necessary.
Check our cases of paddle shift installation.
Please read bellow for full information and photos
Geartronics around the world
- Sold more than 500systems
- Used for the entire grid of 2008-2009 Euroseries3000 (Lola B02/50 F3000)
- Used by Radical for SR3 and SR8 (GCU only)
- 2014 Ginetta SuperCup to use system (all grid mandatory)
- Homologated for Ginetta GT4 and GT3 (G50 and G55)
- Used by outright winner of the 2012 Britcar 24hrs (BMW V8 GTR)
- Multiple hillclimb course records and championships, UK and Europe
- Winner Prototype category 12 Hours of Abu Dhabi
- Winner of the 2012 World Time-Attack Challenge (WTAC)
- Reliable -> 24 and 12 hour race wins
- Faster and much more precise than manual shift: clutchless up & down shifts occur in typically 50-60mS or less, the limit being gearbox type & engine inertia. That means the paddleshift will shift as quick as your mechanical installation will allow while being safe for components
- Reduced gearbox dog wear with up to three time more mileage on dog rings
- Near constant power delivery to the wheels, reducing or even eliminating vehicle instability during shifts.
- Pneumatic (compressed air) actuation, as used at Le Mans and other top level series by factory teams.
- Improved car control with both hands kept on the steering wheel at all times. You can focus on other aspects of car control and improve your laptime.
- No more shifting when you can, instead shift at anytime you need without car movement letting you use everything your engine has to offer.
- Eliminates over-revs, and includes sophisticated strategies to protect engine and gearbox.
- So fast in downshift that if your engine and gearbox allow it will be the speed of your fingers on the paddle that will be the limit in queued downshifts. (up to 5 down-shifts in less than 0.7 second) direct result being shorter braking distances.
- Optional automatic up-shift at desired RPM and 'stacked' down-shift pre-select modes. Note: the auto modes are disabled in firmware and available ONLY if your series allow it or for racing schools.
- Track support available on request.
Futures in detail:
Lightning fast full-throttle up-shifts and smooth clutchless auto-blipped down-shifts all based on a sophisticated 'anti-push' strategy managed in closed loop on the gearbox position sensor.
State of the art gearbox control unit (GCU) with strategies fully closed-loop to control the shift, engine torque reduction and throttle blip.
Please note: This is NOT a timer based system, all shift events are dynamically controlled, based on barrel position feedback.
The GCU works with these inputs:
- gear position sensor,
- engine tachometer,
- throttle position sensor,
- clutch position sensor,
- pneumatic pressure sensor
- paddle switches.
- All analogue inputs are 10 bit resolution for greater accuracy.
The professional 'GCU3' adds:
- 2 x 1-Mbit CANbus interfaces
- additional protection strategies based on speed, wheel slip and gearbox temperature.
Built in safety strategies preventing potentially dangerous shifts, such as attempting down-shifting which would cause over revvs, All features are included as standard and can be disabled in software if so desired.
Closed-loop engine torque reduction by direct interface to engine management system, or by direct connection to ignition coils power supply or by CAN if engine management allows.
Data logging including:
- gear shift count (up & down for each gear),
- fastest & slowest up & down shift times for each gear,
- barrel overshoot or 'kick-back' count & measurement,
- barrel sensor error count,
- pneumatic pressure,
- compressor duty cycle & engine/gearbox run-time counter,
- declined downshift counter
- Logged data can be exported as an Excel sheet.
The paddleshift comprises:
- 12v low current compressor,
- Custom designed accumulator,
- Proprietary gearbox actuator with metallic seals, NO TEMPERATURE PROBLEM
- throttle blipper & valve assemblies to fit every need,
- conventional twin paddles GT or single seater version or single 'rally' paddle,
- replacement hall effect gear position sensor
- Closed-loop GCU with proprietary PC setup software,
Formula paddles to mount between the wheel and quick-release with bespoke carbon-fibre brackets. These neat and ultra lightweight assemblies are fitted with carbon fibre flippers and have an extremely positive tactile feel. These paddles can be supplied with a hand-made 'Raychem' coiled cable at extra cost. Weight: 165g. (without cable) Please note: We do not supply these paddles for use with competitors systems.
Saloon cars generally require larger paddles, and this 'GT' paddle assembly is for a 330mm steering wheel, including a carbon fibre bracket to mount to a standard 6 bolt hub. Other brackets can be made to customer specification. These paddles feature the same switch assembly as our 'formula' paddles, offering an extremely tactile 'clicky' feel through the use of high-powered neodymium magnet technology.
Shift paddles for rally cars require a different approach. Designed to be mounted to the steering column, the 'rally' paddle remains in the same position, regardless of steering wheel position. The two-way actuation is pulled for upshifts & pushed for downshifts. No more comprimising with twin paddles and hitting the wrong one when entering or exiting corners! Please note that we do not supply this unit as a separate item, and it is only available as part of a complete system.
Our GCU is specifically made for paddleshift operation and is designed and assembled in-house. Geartronics don't use electronics from 3rd party suppliers and brand it as our own. Hand assembled prototypes undergo extensive bench & field testing before being put into production. The GCU is constructed using state-of-the-art multi-layer surface-mount technology. The PCB is also conformal coated to ensure the highest levels of relaibility in harsh enviroments.
Customers requiring a high-end solution now have the option of choosing our latest CANbus based 'professional' GCU. This latest development takes high-performance gearshifting to the next level. Designed to integrate with the latest engine management, power switching and data acquisition systems, the unit can send and receive up to 80 channels of CANbus data at speeds of up to 1000Hz.
The calibration software has an array of user definable parameters to ensure that the correct shift strategy is achieved for every installation. Note that this is not a timer based system, and unlike some other systems, you do not need to adjust numerous timer parameters for engine cut, actuator & blip durations! All events in the shift sequence are dynamically controlled in real-time to ensure fast, reliable and consistent shifts under all conditions. The GCU also features a detailed datalogging system that allows the race engineer to fine tune the system.
The quality of the wiring harness is extremely important in a serious racecar application. That's why all Geartronics harnessesare manufactured to very high standards using Raychem spec-55 wire, DR25 sleeving and Deutsch Autosport (AS) connectors (where budgets permit). For customers who are concious of the cost of a full Autosport spec loom, we can also provide looms using Sureseal or Deutsch 'DTM' connectors. We NEVER use cheap braided sleeving or 'bullet' & 'spade' connectors in the construction of any of our looms!
This is our standard gearbox actuator. Weighing just 300g, it's considerably smaller and lighter than an equivalent electric solenoid and presents no packaging issues around the gearbox. Furthermore, being pneumatic, it maintains a consistent performance across the full operating temperature range. It provides a shift force of up to 750N at a maximum operating temperature of 230C.
The Geartronics remote valve assembly uses direct operating 'poppet' valves for reduced susceptibility to dirt ingress. The valve performance allows 5 down-shifts in less than 1 second (depending upon engine response). Valve electrical connections are fully sealed and use Raychem Spec55 wire and DR25 sleeving for ultimate reliability. Weight: 480g.
The 'professional' valve assembly offers increased performance and high temperature consistency. Electrical connection is via a Deutsch Autosport 'ASL' connector, giving the highest levels of reliability available to the professional market. Endurance reliability is further enhanced by the use of integral AV mountings. A 2-way version is also available for DBW applications.
Throttle blipping for clutchless down-shifting is often one of the more challenging aspects of an installation. Every car is different, and we need to cater for all eventualities. In the ideal world we would use a small cylinder like this to operate the engine throttles directly. It provides a force of up to 180N from a weight of just 75g.
An alternative to the 'push-type' blipper is this cable operating unit. It's designed to mount directly onto most throttle bodies and operates with a standard 7mm OD cable. The blip magnitude is easily adjustable by means of the 'K' nut on the rear of the unit. Pull force up to 220N.
The Geartronics system uses a purpose designed air accumulator so that the compressor only needs to operate intermittently (typically 20-25% duty cycle). The accumulator pressure is controlled by the GCU, based on feedback from the high-quality pressure sensor. The advantage that our accumulator has over other air systems is that the output regulator maintains the shift pressure for consistent shift performance, even during a rapid downshift sequence. The unit is also fully rebuildable, unlike tanks of welded construction. The volume of the accumulator allows up to 15 shifts between compressor operations.
For circuit race & rally cars, a small on-board compressor is used to provide the power to make the shifts. This high specification unit is fully stripped, inspected and modified to provide very high levels of reliability. Operating at typically 20-25% duty cycle, the compressor current is just 13 amps, and therefore does not place any high transient demands on the vehicle electrical system. For hillclimb and sprint applications the compressor is replaced with a lightweight high-pressure (300bar) air bottle that can provide enough air for more than 500 shifts.