Engineering:Shift time
Shift time refers to the time interval between gear changes in a transmission. This interval is the time in which power delivery is transferred to the next selected gear, and engine speed is reduced or increased to synchronize the speed of the next gear. Shift time is usually in reference to motor vehicles, but can apply to any gearbox.
Reducing shift time is important in performance and racing vehicles because upshifting generally interrupts power delivery to the wheels. Shift time in a manual gearbox is dependent on the driver, but in automatic or automated manual cars, the electronic or hydraulic control system must be calibrated and tuned to execute fast gear changes. Generally, a dual-clutch transmission shifts faster than a standard hydraulic automatic transmission with a torque converter or a single-clutch automated manual transmission. This is possible because the DCT can pre-select the next gear and switch between its two separate clutches to the next pre-determined gear, thus reducing shift times. Using a freewheel may reduce shift time, as it may not be necessary to use the clutch. A shift kit is also intended to reduce the shift time of a manual vehicle.
With a manual transmission, upshift time can be reduced by installing a lighter flywheel. During an upshift, the engine speed must decrease to synchronize with a higher gear; a lighter flywheel will allow the engine speed to drop more quickly, leading to shorter shift times.
Shift times
- A long shift time is considered anything over 625 milliseconds.[1]
- The average manual car driver takes between 500 ms and 1 s to perform vertical gear changes (i.e. 1st-2nd, 3rd-4th, 5th-6th) and 1 - 2 s to perform horizontal gear changes (i.e. 2nd-3rd, 4th-5th). Shift time is also dependent on gear throws (distance between gears), ease of movement, ergonomics of the gear stick, and gearbox condition. [citation needed]
- For reference, the time it takes for a human to blink can be as quick as 100ms[2] (.1 seconds)
Example upshift times
Please note that manufacturers may have different definitions of shift times.
| Vehicle | Transmission model | Transmission type | Shift time (ms) | Notes |
|---|---|---|---|---|
| McLaren 675LT | 7 Speed SSG | Dual-Clutch | 40[3] | According to MotorTrend Article |
| Lamborghini Aventador | Graziano ISR | Automated manual | 50[4][5] | |
| Ferrari 430 Scuderia | Graziano F1 | Automated manual | ||
| Ferrari FXX Evoluzione | Graziano F1 | Automated manual | ||
| Maserati GranTurismo MC Stradale | Maserati MC Race Shift | Automated manual | With Race mode active | |
| BMW M5 (E60) | BMW SMG III | Automated manual | 65-250[6] | |
| BMW M3 (E46) | BMW SMG II | Automated manual | 80[7] | |
| BMW M3 (E92) | BMW M DCT | Dual-clutch | ||
| Ferrari FXX | Graziano F1 | Automated manual | 80[8] | |
| Maserati Coupé ("4200 GT") | Graziano Cambiocorsa | Automated manual | 80[7] | |
| Shelby GT500 (3rd generation) | Tremec TR-9070 | Dual-clutch | 80[9] | |
| Bugatti Veyron | Volkswagen Group DSG | Dual-clutch | 100[10] | |
| Mercedes-Benz SLS AMG | Mercedes-Benz AMG SpeedShift | Dual-clutch | ||
| Lexus LC 500 | Aisin WR10L65 | Hydraulic automatic | 120[11] | |
| Renault Clio RS 200 EDC Trophy (4th generation) | Renault EDC | Dual-clutch | <120[12] | With Race mode active |
| Chevrolet Camaro ZL1 (6th generation) | Ford-GM 10L90 | Hydraulic automatic | ~150[13] | |
| Ferrari Enzo | Graziano F1 | Automated manual | 150[7] | |
| Nissan GT-R | BorgWarner GR6Z30A | Dual-clutch | 150[14] | With R Mode active |
| Dodge Challenger (3rd generation) and Charger (7th generation) | ZF 8HP | Hydraulic automatic | With Track mode active | |
| Lexus LFA | Aisin SA6 | Automated manual | ||
| BMW M3 (E36) | BMW SMG I | Automated manual | 220[7] | |
| Aston Martin Vanquish | - | Automated manual | 250[7] | |
| Ferrari 575M Maranello | Graziano F1 | Automated manual | 220[7] | |
| Ferrari 360 | Graziano F1 | Automated manual | 250[7] | |
| Lamborghini Huracan Performante | - | Dual-clutch |
See also
References
- ↑ "Tech Tips: Understanding TAP". Automotive Service Association. Archived from the original on 2006-10-03. https://web.archive.org/web/20061003094603/http://www.asashop.org/autoinc/aug2004/techtips.cfm. Retrieved 2006-07-29.
- ↑ "Blink and you miss it!" (in en). http://www.ucl.ac.uk/media/library/blinking.
- ↑ Walker, William (2016-02-16). "2016 McLaren 675LT First Test Review". https://www.motortrend.com/features/2016-mclaren-675lt-first-test-review/.
- ↑ "Oerlikon Graziano and Vocis Driveline Controls develop step change in transmission technology for new Lamborghini flagship - Oerlikon Graziano" (in en). https://www.oerlikon.com/graziano/en/media/press-releases-detail/8206/.
- ↑ Radu, Vlad (2021-07-02). "The Aventador's ISR Gearbox: How It Works and Why Some Owners Complain About It" (in en). https://www.autoevolution.com/news/the-aventador-s-isr-gearbox-how-it-works-and-why-some-owners-complain-about-it-164507.html.
- ↑ Lewin, Tony (30 September 2016). The BMW Century: The Ultimate Performance Machines. Motorbooks. p. 137. ISBN 9780760353042. https://books.google.com/books?id=3I8yDQAAQBAJ&q=bmw%20e39%20transmission&pg=PA137. Retrieved 21 July 2017.
- ↑ 7.0 7.1 7.2 7.3 7.4 7.5 7.6 "Volkswagen makes way for DSG". Paul Tan. http://paultan.org/archives/2006/06/26/vw-phases-out-automatics-makes-way-for-dsg/. Retrieved 2006-08-11.
- ↑ "Ferrari FXX Breaks Cover". Piston Heads. http://www.pistonheads.co.uk/news/default.asp?storyId=12602. Retrieved 2006-09-23.
- ↑ "Stunning Performance and Control: 2020 Shelby GT500 Achieves Supercar Acceleration with 760 Horsepower and 7-Speed Dual-Clutch Transmission". https://media.ford.com/content/fordmedia/fna/us/en/news/2019/08/05/stunning-performance-and-control-2020-shelby-gt500.html. Retrieved 9 June 2020.
- ↑ "Bugatti Veyron Super Sport Technical Specifications". https://www.bugatti.com/fileadmin/media/Media/Veyron/Super_Sport/Technical_Specifications_Bugatti_Veyron_16.4_Super_Sport.pdf.
- ↑ "MY19 Lexus LC500 Sales Brochure". https://www.lexus.com/documents/brochures/2019/MY19-Lexus-LC-LCh-Brochure.pdf.
- ↑ "New Clio R.S. 200 EDC: 'à la carte' sports performance". Renaultsport. http://media.renaultsport.com/New-Clio-R-S-200-EDC-a-la-carte.html?lang=en. Retrieved 2014-03-09.
- ↑ "Camaro ZL1's Lightning-Fast Transmission is a Perfect 10" (in en). media.gm.com. https://media.chevrolet.com/media/us/en/chevrolet/home.detail.html/content/Pages/news/us/en/2016/may/0511-10speed-chevrolet.html.
- ↑ "LAUNCH CONTROL: MY20 NISSAN GT-R IS READY FOR TAKE-OFF" (in en-GB). 2019-08-30. https://uk.nissannews.com/en-GB/releases/launch-control-my20-nissan-gt-r-is-ready-for-take-off.
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