Hopefully by this point you are comfortable with driving a vehicle equipped with a manual transmission. If you are new, I have another article that is a great starting point for beginners. In the previous article, I briefly went over how a manual transmission works. If you haven’t read that yet I highly recommend checking it out here. Knowing how a manual transmission works, will give a good background as to why these techniques are used frequently by experienced drivers. As well as keeping you aware what can happen if these techniques are not properly executed. More on that as we go, but with out further or do let us a take a look at the first shifting technique.
Rev Matching
As the name implies, this technique involves you the driver matching the revs of the engine flywheel. With the clutch that is spinning with the rest of the drive train when shifting gears. This is the easiest technique I personally found to learn first. As you will see later this technique is used with the other two shifting techniques. Mastering this technique will be the foundation for the other techniques I will show you.
The first thing to note before rev matching, you will want to let your engine fully warm up first. Secondly be smooth when trying this, revving your engine too high on downshifts can cause added wear to your clutch. I would also try it at first in a safe area like a race track or empty parking lot. We claim no responsibility for property damage or injury that could occur. Now that we have that safety warning out of the way, let’s get into how to rev match.
The rule of thumb when rev matching, is shifting from a lower gear to a higher gear the engine revs must drop to match the speed of the drivetrain. This is something you might already do, ever notice when you have a smooth transition when shifting to a higher gear? Now what about going from a higher gear to a lower gear? Well you do the opposite, in other words you will need to give the gas pedal a moderate tap with your right foot right before releasing the clutch.
You will know you have a perfect rev match when there is no weight transfer, until you accelerate. If you down shift a gear with out rev matching when driving faster. It will cause a sudden transfer of energy that causes the car to lurch. This weight transfer can be dangerous, and can cause cars to spin out of control. This is exactly why race car drivers, and car enthusiasts practice rev matching.
Heal Toe Downshifting
When you need to slow down you will need to down shift gears, or else the car will stall. However if the car is moving fairly quick you will still want to rev match your gear changes. However this situation requires three pedals to be used at once, and we only have two feet. So this requires one of our feet operating two pedals at the same time.
That foot will be your right foot, where your left foot will operate the clutch as normal. There is two ways to position your feet for this. One is putting your toe end of your shoe on the brake pedal and your heal on the gas pedal. This is typically how it should be done however taller drivers like my self find this harder to do. So instead you can put the left side of your shoe on the brake and right side on the gas pedal. If you find yourself using the second method you will want wider toe shoes.
Double Clutching
This one isn’t really that important on modern cars, but it still comes in handy. Plus once you are comfortable with the above two shifting techniques, this one will be quick to learn. Double clutching is a slightly different type of rev matching, that allows the internals of the transmission to match up better. Non synchronized transmission common on motorcycles, tractors, and semi trucks are shifted this way.
Just like rev matching you will want to match your engine revs with the speed of the drive train. The only difference is this time you will do this with transmission in neutral with the clutch fully released. Now when it comes to the clutch you will press and release it twice hence double clutching. The first time is for taking the transmission out of gear and into neutral. Second time is for going into your next gear from neutral, once the engine revs are properly matched.
I personally find shifting from a lower to higher gear the hardest to master with this technique. It requires you to perfectly time the shift, where downshifts are more at my own pace. If you shift to slow, you can always give a little throttle a blip to match the revs again. Now this technique isn’t the most necessary, but it actually can help prolong the life of your transmission. Because when you double clutch, it basically reduces the speed difference your synchro rings would other wise endure.
I personally use this technique if I want to skip a gear in the transmission. While the topic of skipping gears is controversial, and I would rather not open that can of worms. I am of the opinion that double clutching when properly done virtually does no harm to the synchromesh assembly. It may also help to double clutch if you have a worn synchro ring on your car. Out of all techniques this is the one your transmission will appreciate the most.
Practice Makes Perfect
I hope there was something you where able to take away from this article. With this knowledge you can help prolong the life of your transmission, and have smoother gear changes. Keep in mind this knowledge is only good if you practice and get good at these techniques your self. With all this said and done, I appreciate anyone who read this far!