Short shifting - is it alright!
Discussion
Can anyone settle an arguement for me - is short shifting dangerous in bad conditions? A view point strongly given to me by someone who tows things alot is that short shifting and accelerating actually releases more torque than going through the gears normally. Hence if you short shift and accelerate in wet/icy conditions the arse will break away quicker than if you drive normally. Is this right?
Running high gears in poor conditions is for people with no throttle control as the hp at the wheels is reduced by not running a low gear, low gear multiply the torque of the engine by the gear ratio.
If you have good throttle control, use a gear you think is suitable, if that's a low gear so be it .. i prefer lower gears as it gives more precise / accurate control over wheel speed should they spin up .. I know Peter H (greenV8S) uses lower gears in poor conditions to delberately slide the back which reduces the *unexpected* happening .. ie you've already got it sliding so how much worse can the situation get? ..
The use of high gears in poor conditions is for people who can't drive IMO*
however having said that, Jackie Stewart in his book *principles of performance driving* advocates the use of higher gears in poor conditions and no-one would argue that he couldn't control a car!!!
If you have good throttle control, use a gear you think is suitable, if that's a low gear so be it .. i prefer lower gears as it gives more precise / accurate control over wheel speed should they spin up .. I know Peter H (greenV8S) uses lower gears in poor conditions to delberately slide the back which reduces the *unexpected* happening .. ie you've already got it sliding so how much worse can the situation get? ..
The use of high gears in poor conditions is for people who can't drive IMO*
however having said that, Jackie Stewart in his book *principles of performance driving* advocates the use of higher gears in poor conditions and no-one would argue that he couldn't control a car!!!
cerbagriff said:
Can anyone settle an arguement for me - is short shifting dangerous in bad conditions? A view point strongly given to me by someone who tows things alot is that short shifting and accelerating actually releases more torque than going through the gears normally. Hence if you short shift and accelerate in wet/icy conditions the arse will break away quicker than if you drive normally. Is this right?
I agree with trackcar above.
I think your mate is talking more about the continual build up of spin if you don't bring the first spin under control.
On a greasy surface, if the wheels were spinning in first and you quickly change up to second, it is easy to continue that spin - as it is if you quickly go up to third too.
This is probably where your mate see's problems arising as you could find yourself easily spinning in 3rd or 4th which is then less easy to control due to the lack of torque available as found in gears 1 and 2 (i.e lower gears).
Does this make any sense?
Short-shifting can be quicker. Wheelspin (more likely in the lower gear) and a gearshift itself cost time so on a wet day you may elect to drive out of a corner in 3rd that you might otherwise have used 2nd for.
The school of thought about "use 2nd in the snow" etc. is to help the, erm, less gifted get out of their drive. I don't think that's to be confused with a considered choice of ratio based on the prevailing conditions and that which you want to achieve - be that a drift, a quick exit or lurid burnout.
The school of thought about "use 2nd in the snow" etc. is to help the, erm, less gifted get out of their drive. I don't think that's to be confused with a considered choice of ratio based on the prevailing conditions and that which you want to achieve - be that a drift, a quick exit or lurid burnout.
I don't think short-shifting is for people who can't drive - it's often a faster way to travel even though it feels slower and less dramatic.
Part of the reason that we led for so long at the Silverstone GT race in the rain, on slicks, last August, was that Phil was only using 4th and 5th gears and driving very steadily while others were trying to use 3rd in many of the corners (Complex/Beckets/Club) and lighting the back up straight away.
Phil drove like my mother, but he carried on extending our lead over the wet tyre runners in all but the worst conditions.
Part of the reason that we led for so long at the Silverstone GT race in the rain, on slicks, last August, was that Phil was only using 4th and 5th gears and driving very steadily while others were trying to use 3rd in many of the corners (Complex/Beckets/Club) and lighting the back up straight away.
Phil drove like my mother, but he carried on extending our lead over the wet tyre runners in all but the worst conditions.
I think Joolz summed it up pretty well. Being in a higher gear makes it easier to avoid wheelspin. It also makes wheelspin far more dangerous if you have ample torque for the conditions and are not poised to correct wheelspin when it occurs.
In competitive conditions, if you have more torque available than you can put down in a lower gear and you have enough control to be sure that you can avoid or correct wheelspin if it occurs, then taking a higher gear makes sense.
Under normal road conditions, if you know that there is not enough torque to spin the wheels in the higher gear then taking the higher gear makes it easier to avoid wheelspin and is safer.
The nightmare situation is where you take a higher gear to avoid wheelspin, and then something unexpected happens and you spin the wheels anyway. Spinning the wheels in a higher gear is much much harder to recognise and recover than in a lower gear. Unless you are very quick off the mark it can all be over before you're even noticed it, leading to reports that the car spun with no warning and so on.
I reckon that staying in a lower gear is safer because the chances of being surprised by a large slide are much lower. This is particularly applicable if you have a big torquey engine running on low throttle openings well below peak torque; the slightest loss of traction or twitch on the throttle pedal can start the wheels sliding and once sliding the torque rises which makes the wheel speed flare up. Being in a high gear means that a given rpm change gives much more slip at the wheels in mph terms and the wheel speed can flare up a long way very quickly. Once it's started, it's very difficult to get that back.
In competitive conditions, if you have more torque available than you can put down in a lower gear and you have enough control to be sure that you can avoid or correct wheelspin if it occurs, then taking a higher gear makes sense.
Under normal road conditions, if you know that there is not enough torque to spin the wheels in the higher gear then taking the higher gear makes it easier to avoid wheelspin and is safer.
The nightmare situation is where you take a higher gear to avoid wheelspin, and then something unexpected happens and you spin the wheels anyway. Spinning the wheels in a higher gear is much much harder to recognise and recover than in a lower gear. Unless you are very quick off the mark it can all be over before you're even noticed it, leading to reports that the car spun with no warning and so on.
I reckon that staying in a lower gear is safer because the chances of being surprised by a large slide are much lower. This is particularly applicable if you have a big torquey engine running on low throttle openings well below peak torque; the slightest loss of traction or twitch on the throttle pedal can start the wheels sliding and once sliding the torque rises which makes the wheel speed flare up. Being in a high gear means that a given rpm change gives much more slip at the wheels in mph terms and the wheel speed can flare up a long way very quickly. Once it's started, it's very difficult to get that back.
I agree with v8s and joolz, but the only real time you should be short shifting is when you are about to enter a certain peice of track that could possibly need a gear change mid corner, obviously this unsettles the car so you are better of going for a higher gear and a smooth corner, short shifting because you are getting wheelspin from a start line is because of one thing!! you is putting your foot down too hard for the grip of the car too handle! instead what you should be doing IMHO is nursing the power you have, ie instead of planting your throttle do it in 3 stages, put your foot down a bit then a bit more then the whole lot! I have always been renowned form getting away from the grid very quickly and its not rocket science!! its all about nursing the power you have!!
Easiest way of sorting this...take 90% of any advice given to you and regard it as comming from ppl who cant drive. Take the remaining 10% and consider it useful. You are lucky on this thread as it is comming down as a fairly even split, so that last 10% should give you basically a "whatever floats your boat" style...and that pretty much answers every driving technique question you will ever have. Always reduce it down to the lowest common denom and presume the ppl around you on the road cant drive and the ppl you are asking advice from cant drive either...that way you arent expecting magical solutions from elsewhere. There is no absolute right or wrong way to drive on the roads these days, just how you feel safest and in the most control. Personally I short shift sometimes and keep in gear at others depending on how Im feeling/reading the road and situation at the time. I heartily suspect the majority of others do also. Just do what you do to feel you are keeping it under control.
As I get older I find that I tend to stay in higher gears more of the time, on the track. There are corners where at one time I would have dropped a cog under braking and then hit the rev limiter on the way out, staying in a higher gear feels slower but avoids two gear changes, makes it easier to concentrate on line and speed and reduces the time coasting on the way out of the corner. Sometimes there's nothing in it. Other places you only need to find an extra few mph through the apex to stay on cam and then the gains can be quite noticeable. But in any case, it's much easier on the car and driver. This was one of the reasons I decided to go for a really fat torque curve on the V8S rather than going for absolute power. By eliminating half a dozen gear changes per lap I stand to gain far more than I'd get from just a power hike.
trackcar said:There was me thinking I was the only one to do that! Always best to know EXACTLY how much grip is available IMHO.
I know Peter H (greenV8S) uses lower gears in poor conditions to delberately slide the back which reduces the *unexpected* happening .. ie you've already got it sliding so how much worse can the situation get? ..
greenv8s said:
By eliminating half a dozen gear changes per lap I stand to gain far more than I'd get from just a power hike.
All the best advice I've ever had on track (and then tried out - and then lapped quicker) usually involves the phrase - "...and, see, you've saved yourself a gearchange..."
I got a terminal velocity 6mph faster at Brands with Clubsport's sage comments and 12mph at Castle Combe with an excellent chap (PCGB racer) whose name is currently escaping me...(its going to bother me for hours, now...)
Going back to the original question for a moment "is short shifting dangerous in bad conditions?" the answer IMHO is definately no! What is dangerous is not knowing how bad the conditions are. As already discussed you are less likely to break traction in a higher gear for a given amount of welly which in a car of modest power means maybe not at all. Our problem is that we have more than enough at any time!
An old school tip in slippery conditions is to move the seat back a notch. That way you are lighter on the throttle and the brakes. This makes it fun when conditions are good as when you move it back the car suddenly seems faster than it ever was ;-)
Cheers
An old school tip in slippery conditions is to move the seat back a notch. That way you are lighter on the throttle and the brakes. This makes it fun when conditions are good as when you move it back the car suddenly seems faster than it ever was ;-)
Cheers
victormeldrew said:
I know Peter H (greenV8S) uses lower gears in poor conditions to delberately slide the back which reduces the *unexpected* happening .. ie you've already got it sliding so how much worse can the situation get? ..
...and give it away before you start leaving very little room for control!
only for the extremely gifted...and slow. If you only have a little grip - use it don't loose it!
ahonen/bosscerbera seem to be right on IMHO!
i'm sure Peter didn't mean
"its could silde here...best kick it out now just in case!" Fun tho it is
Guillotine said:
i'm sure Peter didn't mean
"its could silde here...best kick it out now just in case!" Fun tho it is
It's not a technique I recommend for road use, but sometimes that's exactly what I do. If you don't know how much grip there is then you have two choices: drive conservatively so you never slide, or find where the limit of grip is as quickly and safely as possible. Experience makes it easier to guess, but there's no substitute for taking the tyre past the limit of grip to find where the limit is. During practice runs when I need to find what condition the track is in I deliberately provoke small slides all over the place, hence the nickname 'squeally Pete' when I was running Yokohamas because the tyres used to chirp continuously. The harder I am trying and the closer I am to the limit of grip the less provocation it takes, when I am on the ragged edge it is continuously on the point of sliding and I do everything I can to keep it smooth and stop it breaking away. If I get it right then to an observer it might look as if everything is calm and steady, but if I get it wrong and the corrections get bigger then it looks as if I am fighting the car into every corner. Sprinting is all about getting from 'wrong' to 'right' as quickly as possible.
On public roads I normally take the other choice and stay well back from the limit of grip, but if there's any chance that the car is going to slide then I'll go out of my way to find how much grip there is first.
I can't remember if it was Randy Mamola or Kenny Roberts, but they once described racing a 500 GP bike as like running along the top of a concave clifftop. You're going fastest when you are taking small leaps across the abyss, with each footfall on the cliff. Most of the time though you are over the edge. Not entirely sure its an appropriate analogy here, but I just remembered it.
Its always good to know where the limit is, or how do you know how close you are to it? Otherwise you are just pushing your luck.
A slightly separate debate though to whether short shifting is OK.
>> Edited by victormeldrew on Saturday 4th February 16:36
Its always good to know where the limit is, or how do you know how close you are to it? Otherwise you are just pushing your luck.
A slightly separate debate though to whether short shifting is OK.
>> Edited by victormeldrew on Saturday 4th February 16:36
horses for courses i guess.
limited adhesision as controlled slides (powersliding/drifting) used to be standard in all motorsport even F1 in the 80s, but this was in the dry and due to the more hp than adhesion nature of the cars due to low downforce.
generally speaking, on the limits of adhesion is quickest. even a powerslide has adhesion...or its a spin and could therefore be commented on as the "limit"!
and short shifting is anb excellent method of keeping the car out of the powerband IF you have a std TVR toppy power curve. don't think that applies to the V8S pete.
BTW thats the first time I've been called conservative
limited adhesision as controlled slides (powersliding/drifting) used to be standard in all motorsport even F1 in the 80s, but this was in the dry and due to the more hp than adhesion nature of the cars due to low downforce.
generally speaking, on the limits of adhesion is quickest. even a powerslide has adhesion...or its a spin and could therefore be commented on as the "limit"!
and short shifting is anb excellent method of keeping the car out of the powerband IF you have a std TVR toppy power curve. don't think that applies to the V8S pete.
BTW thats the first time I've been called conservative
Short shifting is more dangerous if the conditions are slippery e.g. muddy or icy roads, and if your right foot is a bit heavy and you have an engine with a lot of low down torque (e.g. Griff 500). I speak from experience. Another thread from a long time ago explained it better, but imagine being in third at around 1500 revs and basically flooring it, on a straight road you didn't expect to be coated with a thin layer of mud (or ice or whatever). In a car with low torque at low revs in third you'd gradually pick up speed until you were going fast enough to want to ease off. In the Griff you pick up speed very rapidly, the torque is enough to break traction on the slippery road, especially as it comes in a rush at about 2500/3000 revs then you find that its much harder to control the engine power and revs in third gear as you are starting to slide than in 1st or 2nd. The torque is what catches out new Griff/Chimaera drivers much more so than the power (I'd driven cars as powerful before).
Someone else on the thread with proper racing experience explained why, and that they generally stuck to lower gears in slippery conditions - another way of saying it is if you are going to lose grip then better to do it in 1st than 3rd because you will be going so much slower for the same revs/torque.
I realise this isn't a good way to drive. I did it once and won't ever do it again, but it does illustrate the point about why short shifting can be dangerous (and faster when you have good conditions and do it right). Obviously if you have good control and are sensitive to road conditions it doesn't really matter what gear you are in from a safety point of view.
gooner
Someone else on the thread with proper racing experience explained why, and that they generally stuck to lower gears in slippery conditions - another way of saying it is if you are going to lose grip then better to do it in 1st than 3rd because you will be going so much slower for the same revs/torque.
I realise this isn't a good way to drive. I did it once and won't ever do it again, but it does illustrate the point about why short shifting can be dangerous (and faster when you have good conditions and do it right). Obviously if you have good control and are sensitive to road conditions it doesn't really matter what gear you are in from a safety point of view.
gooner
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