Best way to downshift?

[jrider36]

I was wondering if you rev match with the pdk transmission. I was also wondering what is rev matching? Of course I have researched the topic but I have never gotten my head completely around it. My experience with a traditional manual is very limited. I find myself shifting about 90% of the time and would consider purchasing a manual in the future. For now, I love the freedom to shift when I want...


Thanks,

Justin R.

[thstone]

Originally Posted by jrider36

I was wondering if you rev match with the pdk transmission. I was also wondering what is rev matching? Of course I have researched the topic but I have never gotten my head completely around it. My experience with a traditional manual is very limited. I find myself shifting about 90% of the time and would consider purchasing a manual in the future. For now, I love the freedom to shift when I want...


Thanks,

Justin R.

Rev matching is moderating the engine speed so the engine output shaft and the transmission input shaft are at nearly the same RPM when the clutch is engaged. This will minimize clutch slippage, wear, and help keep the car balanced.

Most drivers tend to do this already somewhat naturally on upshifts by moderating the throttle in the middle of the upshift to ensure that the clutch engagement to the next higher gear is smooth. For example, when shifting up at high RPM's, the driver will naturally give the engine more throttle when engaging the clutch for the next gear.

Rev matching is doing the same thing for downshifts - especially if you want to keep the rev's in the upper range through a corner (instead of letting the rev's fall to idle or nearly idle). The tricky part is that the driver is usually also braking at the same time - thus the technique known as "heel and toe" is used to brake and perform a rev-matched downshift at the same time.

PDK transmissions can do the rev matching for you. After receiving the signal to downshift, the computer matches the engine speed to the transmission speed and smoothly performs the shift.

[jb92563]

I always downshift since with the gears engaged you are in full control of your car.

When you are in neutral you cannot accelerate or decelerate with the engine so you have taken away some of your control.

Take a PCA Performance Driving school for a real eye opener on how to drive and control your Porsche.


It takes much practice but rev matching is the goal to minimize wear on the clutch.

It took me 6 months to get it perfect in my Boxster 6 speed and now I can shift smooth going up or down the gears at will.

I do still miss a shift now and then though but I just go back to the previous gear when that happens and try again.

When down shifting I use the blip method where enroute to the next stick position(gear) I blip the throttle to match the revs then let the clutch back in at just the right speed so that everything hooks up perfect without a lot of jerkiness.

When doing Max performance shifting it does get more jerky but smooth stick and clutch work non the less.

You never want to shift down where the new gear ratio over revs the motor.

With 6 speed that does not happen very easily unless you are way up in the revs 6500+ but with a 5 speed you may have to pay a bit more attention.

If you keep all your up and down shifts between 3500-5500 rpm you will have no worries.

Practice is the best way to get smooth, and heel/toe or blip is up to you and what you find is your prefered method.