What is rev matching?

Rev matching, also known as heel-toe downshifting, is a driving technique used primarily in manual transmission vehicles to smooth out downshifts and maintain control, especially at higher speeds or during spirited driving. It involves coordinating three actions simultaneously or in quick succession:

• Blip the throttle: Briefly increasing engine RPM (revolutions per minute) using the throttle. This raises the engine speed to match the speed of the transmission's input shaft as you downshift.

• Depress the clutch: Engaging the clutch smoothly disconnects the engine from the transmission.

• Downshift: Selecting the lower gear.

Why Rev Matching is Important:

• Smoother Downshifts: Without rev matching, downshifting can cause a sudden deceleration and jerk in the car due to the mismatch in engine speed and transmission speed. The engine speed is higher than the speed needed for the gear, causing the driven wheels to momentarily lock. Rev matching prevents this jarring effect.

• Reduced Wear and Tear: Smoother downshifts reduce stress on the transmission, clutch, and drivetrain components, leading to longer component life.

• Improved Control: Maintaining control of the vehicle, especially during cornering or braking, is easier with smoother downshifts. It helps prevent the rear end from sliding, especially in rear-wheel-drive cars.

• Enhanced Driving Experience: While not strictly necessary, it is a skill many drivers appreciate for its refinement and contribution to a more controlled and engaging driving experience.

How to Rev Match:

Learning rev matching takes practice. Here's a simplified breakdown:

1. Brake: Start by braking appropriately for the upcoming corner or speed reduction.

2. Clutch: Depress the clutch pedal smoothly.

3. Heel-Toe (Optional but Common): Use the heel to depress the brake pedal while simultaneously using the toe to blip the throttle. This is the origin of the "heel-toe" name. You can also accomplish this separately with your foot.

4. Downshift: Select the desired lower gear.

5. Clutch Release: Smoothly release the clutch pedal while gently applying throttle to maintain momentum.

Modern Cars and Rev Matching:

Many modern cars, particularly those with automatic or semi-automatic transmissions (like dual-clutch transmissions or some automatic transmissions with paddle shifters), have automatic rev matching features. These systems electronically blip the throttle for you, eliminating the need for the driver to perform the heel-toe technique. However, learning rev matching remains a valuable skill for driving manual transmission vehicles and even provides a degree of feel and control some drivers prefer over automated systems.