Double Clutch & Heel and Toe Downshifting: Advanced Car Driving Technique
BMW M3 racecar cockpit
Worth the practice it requires!
Double-clutching is a racecar driving technique that is rarely heard of by the average person. It can only be performed on a manual transmission vehicle. It involves the driver revving up the engine rpm’s in neutral while shifting down one gear in order to allow for a smoother shift and less stress on the synchros. Proper double-clutching will increase the longevity of synchros.
When one puts a car into a lower gear without double-clutching, the driver and passengers sense a rough feeling when the gear engages. It is often sloppy. When double-clutching, the driver pushes in the clutch with their left foot, but does not immediately put the stick-shift into the lower gear. Rather, they put the stick in neutral for a split second (the motions go quicker when you practice a lot), let off of the clutch pedal, and rev the engine up by pressing the gas pedal with the right foot. While the engine rpm’s are temporarily increased, the driver again presses in the clutch and shifts into the lower gear as quick as possible. This accommodates for the increased engine rpm’s when the vehicle is put into a lower gear. There is little to no stress felt when downshifting with this method. The faster you are going in each gear before downshifting (the higher the engine rpm's already are), the MORE gas you are going to have to give the car in neutral, in order to insure the rpm's match up. Conversely, if you are cruising slowly in 4th gear and would like to double-clutch into 3rd before a more windy part of the road, you would only give a small "blip" of the throttle.
Take your time and do not make abrupt motions.
Proper downshifting can only be acquired with a lot of everyday practice. Be careful not to damage your clutch or gears by being too rough. It is all about being smooth and calm... with your shifting- up-shifting too! After a lot of practice (and it does take a lot of practice), double clutching feels natural, and the driver can effortlessly match the engine rpm’s of the lower gear without much thought. When double-clutching becomes habitual, a driver will never return to the standard method of downshifting. Double-clutching is superior, although it feels very awkward at first.
After double-clutching is mastered, it is advised to learn how to heel-and-toe downshift, which is an even more advanced method of double-clutching. It is the same process, except you brake at the same time, and with the same right foot that you rev the gas pedal with. The "toe" of your right food, or the front left side of the foot, applies brake pressure, while the "heel" or the back right side of the foot taps the gas pedal. Sounds complicated, but it really is simple and comes second-nature after practice.
Be prepared for some awkward, abrupt shifts and loud engine revs when practicing!