Downshifting
 

Hi all

A question on downshifting technique on track. Is there any mechanical concern with downshifting, say, from 5th to 2nd, or 5th to 3rd, or 4th to 2nd?

Or, to get into a bit of minutiae, say, shifting from 5th to 2nd, and running through the gears but NOT releasing the clutch until you reach the desired gear?

Most of the top guys I've rode along with will dutifully go through every gear, blipping and de-clutching accordingly. My skill level is not as high, and I am terrified of going from 5th to 2nd when I am looking for 4th and over-revving.

Ok, I'll take care of this one :)

I blew my engine (my old C2S) at Sebring last year because I couldn't heel & toe with the bucket seats. So I was downshifting from 4th to 2nd and over-revved the engine. And then poof! :D

The best reason to go through each gear is so that you don't over-rev the engine by downshifting multiple gears. When you downshift multiple gears you don't know what RPM you're going to end up in.

If you don't release the clutch there is no reason to run each gear.

Learn to heel-toe through each gear... 5th...4th...3rd..2nd...releasing the clutch with each gear. There is actually a nice rhythm to it that helps with braking. And by keeping the drivetrain engaged, you stop faster and keep the diff locked for more stability during braking. The key is the know when your speed is right for the each gear as you brake. It takes practice to get it done right.. so don't expect to nail it every time at first.

The synchromesh gearbox can easily accomplish a 5-3 or a 5-2 downshift in one motion if you do it late enough in the braking zone.

But.

If you are trying to improve yourself as a driver then doing it sequentially with full clutch release will teach you proper technique in case you get into a real race car. Even if you never get to drive a race car with a sequential unit it is still good to have the technique.

It's not too complicated to do but requires some practice. Initially your braking distances will increase so you might not win the DE championship but you will be doing the E part of DE.

If you are hard on the brakes to slow the car down, going thru the gears and engaging the clutch for each gear makes no sense. You slow the car to the correct speed in the shortest distance possible and engage the right gear. That's just wasted motion and you will end up distracting yourself. Finding the right gear in a hurry is another matter. If it helps you find the gear then by all means go thru the pattern in sequence, but double clutching for each gear just adds wear and tear and slows you down.

I shift from 5th to 3rd after the long straight at my local track, no problems. Make sure you are relaxed and know exactly where the gear shift is, blip the throttle at the correct speed and go into the lower gear. There is less wear and tear on the car using the brakes rather than the transmission, and a lot less work. Some guys just enjoy doing it the other way, or in a race it may be of some use in tricky situations, otherwise why bother. Simple is better in my book.

what ... no one mentioned "get a PDK" ... sheesh you guys are slipping like a GT3 LSD ... :D

it may actually help to release the clutch while passing thru neutral on the way to the lower gear ... you MUST (regardless) ensure that you blip (rev match) the engine before releasing the clutch in the new lower gear ... failure to do so will result in ... 1) a nasty jerk as the revs match, and potentially 2) an overrev situation (say "bye bye valves - hello expensive engine rebuild")

Yeah... PDK it is, and I have used a manual many, many years. I bet next year the first GT3 w/ PDK will be here. :)

Re multiple downshifting... try downshifting from 130MPH to 40MPH, 4th (or 5th) to 2nd on your way to Turn 2 at Laguna. Perhaps it can be done, but I bet it's not pretty.

5th to 3rd is a pretty normal downshift for me, for instance at T1 at the Glen. Just take your time in neutral and I often do 2 blips to be sure the revs are good.

Thanks all.

Am glad I'm not the only one who skips down a gear sometimes. I always blip the throttle, and actually to go from 4-3-2 I find a lot easier than going from 5-4-3. I wind up going 5-3, The 5-4 shift just isn't that comfortable, but then again is the shift that I think most of us have the LEAST experience doing in a hurry.

Looking at the other thread that Slow referred, I didn't really see a consensus, except that skipping a downshift works the synchros harder. How much harder? Does it make a difference?

Am practising as much as I can. But am still a little green - right now my focus is to blip the throttle WITHOUT losing brake pressure, something that I am getting proficient at when downshifting only 1 year (less foot movement) but with multiple downchanges I just can't control the brakes properly...

ONE GEAR AT A TIME, IF YOU CAN'T ACCOMPLISH THAT THEN PDK. YOU THINK Walter Röhrl slams it from 5 to 2? More then likely you only need to go to 3rd.

This equation leaves you with much too much time off of the gas resulting time and position loss IMHO....just sayin'

You may be right but I doubt it. I'm under full brake while this is going on so I can't see how I'm losing time on the gas. OTOH, you're driving and racing an RSR so I assume you know whereof you speak.

At no point on a track should you be in neutral. You should A.) always be in a gear and B.) you must be either on gas or braking..never coasting. If you need to avoid something, how can you in neutral? What if your braking and someone spins right in front of you and you need to avoid them? That is why race driver downshift thought the gears... as you need to be able to control the car in any situation. And again, your braking will be much more stable with the drivetrain engaged. Start slow and work your up to speed. Each person develops their skills at a different rate. Don't be in a rush. Work on being smooth...and the speed and lower lap times will come. Better to learn the fundamentals and good habits now, so you don't have to change later.