Little question about turbos. Ive never driven one. My understanding is when you get on the gas, the turbo starts to 'wind up' and then kicks in. What shuts the turbo off? Full removal of the throttle or partial? Ive heard in turbo powered race cars that round about the apex you get on the gas, and when the turbo kicks in sometimes you have to back off the throttle a little bit to control the extra power. Will relaxing throttle 'turn off' the turbo again? What about when you upshift?
Turbo driving techniques
Started by
Ross Stonefeld
, Sep 26 2001 14:19
9 replies to this topic
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#2
scarbs
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Posted 26 September 2001 - 15:56
Turbos spin up when the exhaust is blowing, so when the throttle is open the turbo should be spinning and producing boost. Depending on the wastegate used, lifting off the throttle opens the wastegate and the exhaust bypasses the turbo, although the turbo continues to spin it is not creating as much pressure. This antilag system keeps the turbo spinning in the hope it will not lose too much momentum before the throttle is used again and the wastegate closes. This does help but other techniques can be used to improve on it.
Technique for getting off the line
Rev the engine and create boost, this can take a second or so, somewhat embarrassing for Diesel turbo road car drivers.
Technique for exiting corners
In cornering lifting off the throttle drops boost and when the throttle is pressed once more there is the “Turbo lag” wait for the boost to come back in.
The need to “clutch” to change gear, while also braking and keeping the throttle open needs three feet..! Heel and toeing to blip the throttle does not help as the throttle needs a longer time to build up pressure.
The best technique is to use left foot braking, keeping the throttle (right foot) pressed down, making the engine labour against the brakes, keeps the boost up and allows more normal corner exit. This means that gear changes have to be clutchless, which is dependant on your gearbox and mechanical sympathy (or lack there of…)
Technique for in gear acceleration
Keep the engine spinning at all costs, like a two stroke motorbike engine You need to rev the engine hard to keep the boost up. Run in a lower gear to revs and boost up. If the engine does go off boost, pull in the clutch and press the throttle hard, drop a gear if you need to, the revs will rise and the boost comes back in, then dump the clutch. Never try to regain boost by flooring the throttle and waiting for the boost to come in the engine will bog down or take ages to get back on boost.
Technique for in gear changes
As with in gear acceleration it is important to keep the engine spinning, do not short shift the gearbox or the engine will drop out of its boost range. Try keeping the throttle pressed little during changes to keep the engine spinning.
Technique for getting off the line
Rev the engine and create boost, this can take a second or so, somewhat embarrassing for Diesel turbo road car drivers.
Technique for exiting corners
In cornering lifting off the throttle drops boost and when the throttle is pressed once more there is the “Turbo lag” wait for the boost to come back in.
The need to “clutch” to change gear, while also braking and keeping the throttle open needs three feet..! Heel and toeing to blip the throttle does not help as the throttle needs a longer time to build up pressure.
The best technique is to use left foot braking, keeping the throttle (right foot) pressed down, making the engine labour against the brakes, keeps the boost up and allows more normal corner exit. This means that gear changes have to be clutchless, which is dependant on your gearbox and mechanical sympathy (or lack there of…)
Technique for in gear acceleration
Keep the engine spinning at all costs, like a two stroke motorbike engine You need to rev the engine hard to keep the boost up. Run in a lower gear to revs and boost up. If the engine does go off boost, pull in the clutch and press the throttle hard, drop a gear if you need to, the revs will rise and the boost comes back in, then dump the clutch. Never try to regain boost by flooring the throttle and waiting for the boost to come in the engine will bog down or take ages to get back on boost.
Technique for in gear changes
As with in gear acceleration it is important to keep the engine spinning, do not short shift the gearbox or the engine will drop out of its boost range. Try keeping the throttle pressed little during changes to keep the engine spinning.
#3
scarbs
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Posted 26 September 2001 - 15:56
Left foot braking
Most initial attempts at left foot braking scare most drivers into never trying it again. Your left foot is used to fairly robust uncontrolled stabs up and down on the clutch. Braking needs a little more delicacy.
Learning process
At first try to use the left foot on the brake on medium-fast straight roads (with no traffic). You find you’ll brake a bit harshly (which is fine). But you’ll find you forget to release your foot off the brake, so the brake pressure continues and the car decelerates even more.
The first trick is to train your foot to lift off gently to release the braking pressure. Why you do this I don’t know, I’ve taught a few people to left foot brake and they do the same thing every time. I’d have thought with the left used to controlling the release of pressure of the clutch it would be good at this, but not so.
From there build up the initial pressure to train your foot to press down in a controlled manner, while still also controlling the lift off. Now try this into faster corners where no gear change is needed. Next we go off to a (empty) car park, try bringing the car to a total halt from low speed, you’ll now find this Keep on pressing reflex is more noticeable. When you normally (Right foot) brake a car to halt, unconsciously you release braking pressure as the car comes to a halt, to the point where just as the car stops you’ve release almost al the pressure. With this lack of subconscious control in your left foot the car stops abruptly usually by nose diving and smashing your face into the steering wheel… again repeated practice releasing the pressure with the left foot before stopping give the foot the control it needs for more complex manoeuvres.
Now you should be able to vary the pressure on braking and lifting,
NOTE: Always try this away from other traffic, as sometimes you forget which pedal to push, with rear ending consequences…
To make use of the left foot braking you need also to control the throttle at the same time, again on a faster empty straight road slip the car into neutral left foot brake and blip the throttle repeatedly to get the feel. Once comfortable, try applying pressure to the throttle while left foot braking, to feel the effect. From here the world of left foot braking is literally at your feet,
Places Area to gain.
Non gear change corners:
Left foot brake in all the way to the apex and your right foot can immediately get back on the throttle. This cut the delay in getting on the power.
Slower corners:
Big gains in late are available as with your left foot already over the brake, you can go from power to braking immediately.
Medium speed corners:
With most road cars the improved handling response with a little drag on the brakes make corner entry faster and more accurate. Pressing lightly on the brake with or with out the power on improves the poise of the car.
Fast corners:
With softly sprung road cars in fast bends, going from braking to accelerating upsets the car, You can balance the car by using both the throttle and brake together. On the way in apply the brakes and keep the throttle down, release the throttle more and apply more brakes to slow and balance the car, never lift of the throttle completely, then accelerate at the apex keeping some brake on only releasing them completely when the car is balanced again.
Ultra fast corners:
A dab on the brakes keeps the engine pulling and is better than a lift off the throttle (particularly if your running carbs).
Gear change corners:
Left foot brake in all the way to the apex and blip right foot to change gear (only works in higher gears, 3rd to 2nd is more tricky) and get back on the throttle
Unknown corners, corrections and emergencies
When in rally mode charging around unfamiliar corners a left poised over the brake can either allow for a dab on the brakes to improve turn in, shed speed or come to a big stop when things have gone badly wrong.
There’s no doubt that left foot braking is better in emergencies if the foot is already covering the brakes, a heavy tug on the gearlever puts you into neutral while the left foot is already braking
Up someone’s rear:
Keep the left foot covering the brake, in case of emergencies. When preparing to overtake press the throttle and balance the speed on the brake, when going to pull out release the brake and press the throttle all the way down
Someone’s up your rear:
Dab your left foot on the brake just enough to light up the brake lights, great fun, especially under heavy acceleration really confuses them.
Most initial attempts at left foot braking scare most drivers into never trying it again. Your left foot is used to fairly robust uncontrolled stabs up and down on the clutch. Braking needs a little more delicacy.
Learning process
At first try to use the left foot on the brake on medium-fast straight roads (with no traffic). You find you’ll brake a bit harshly (which is fine). But you’ll find you forget to release your foot off the brake, so the brake pressure continues and the car decelerates even more.
The first trick is to train your foot to lift off gently to release the braking pressure. Why you do this I don’t know, I’ve taught a few people to left foot brake and they do the same thing every time. I’d have thought with the left used to controlling the release of pressure of the clutch it would be good at this, but not so.
From there build up the initial pressure to train your foot to press down in a controlled manner, while still also controlling the lift off. Now try this into faster corners where no gear change is needed. Next we go off to a (empty) car park, try bringing the car to a total halt from low speed, you’ll now find this Keep on pressing reflex is more noticeable. When you normally (Right foot) brake a car to halt, unconsciously you release braking pressure as the car comes to a halt, to the point where just as the car stops you’ve release almost al the pressure. With this lack of subconscious control in your left foot the car stops abruptly usually by nose diving and smashing your face into the steering wheel… again repeated practice releasing the pressure with the left foot before stopping give the foot the control it needs for more complex manoeuvres.
Now you should be able to vary the pressure on braking and lifting,
NOTE: Always try this away from other traffic, as sometimes you forget which pedal to push, with rear ending consequences…
To make use of the left foot braking you need also to control the throttle at the same time, again on a faster empty straight road slip the car into neutral left foot brake and blip the throttle repeatedly to get the feel. Once comfortable, try applying pressure to the throttle while left foot braking, to feel the effect. From here the world of left foot braking is literally at your feet,
Places Area to gain.
Non gear change corners:
Left foot brake in all the way to the apex and your right foot can immediately get back on the throttle. This cut the delay in getting on the power.
Slower corners:
Big gains in late are available as with your left foot already over the brake, you can go from power to braking immediately.
Medium speed corners:
With most road cars the improved handling response with a little drag on the brakes make corner entry faster and more accurate. Pressing lightly on the brake with or with out the power on improves the poise of the car.
Fast corners:
With softly sprung road cars in fast bends, going from braking to accelerating upsets the car, You can balance the car by using both the throttle and brake together. On the way in apply the brakes and keep the throttle down, release the throttle more and apply more brakes to slow and balance the car, never lift of the throttle completely, then accelerate at the apex keeping some brake on only releasing them completely when the car is balanced again.
Ultra fast corners:
A dab on the brakes keeps the engine pulling and is better than a lift off the throttle (particularly if your running carbs).
Gear change corners:
Left foot brake in all the way to the apex and blip right foot to change gear (only works in higher gears, 3rd to 2nd is more tricky) and get back on the throttle
Unknown corners, corrections and emergencies
When in rally mode charging around unfamiliar corners a left poised over the brake can either allow for a dab on the brakes to improve turn in, shed speed or come to a big stop when things have gone badly wrong.
There’s no doubt that left foot braking is better in emergencies if the foot is already covering the brakes, a heavy tug on the gearlever puts you into neutral while the left foot is already braking
Up someone’s rear:
Keep the left foot covering the brake, in case of emergencies. When preparing to overtake press the throttle and balance the speed on the brake, when going to pull out release the brake and press the throttle all the way down
Someone’s up your rear:
Dab your left foot on the brake just enough to light up the brake lights, great fun, especially under heavy acceleration really confuses them.
#4
Ross Stonefeld
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- 70,106 posts
- Joined: August 99
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Posted 26 September 2001 - 16:13
Dude you rule 
I left foot brake in my road car. I consciously dont brake against throttle, but I do use my left foot. My right foot feels funny when I use it in a road car. Though I have to use my right foot in all race cars because ive not yet been in one that has a high enough steering colum for me to get my left foot to the brakes. So I hope it can do okay
thanks a lot man
I left foot brake in my road car. I consciously dont brake against throttle, but I do use my left foot. My right foot feels funny when I use it in a road car. Though I have to use my right foot in all race cars because ive not yet been in one that has a high enough steering colum for me to get my left foot to the brakes. So I hope it can do okay
thanks a lot man
#5
unrepentant lurker
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Posted 27 September 2001 - 01:15
So how do you work the clutch and brake at the same time with one foot.
#6
MattPete
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Posted 27 September 2001 - 02:05
Originally posted by unrepentant lurker
So how do you work the clutch and brake at the same time with one foot.
Clutch??? We don't need no stinkin' clutch!
I guess you do what I had to do when I had surgery on my left knee and couldn't bend it: learn how to shift without using the clutch. Not something I would recomend, but it's a nice talent to have.
#7
Indy2
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- 43 posts
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Posted 27 September 2001 - 03:32
Originally posted by MattPete
Clutch??? We don't need no stinkin' clutch!
I guess you do what I had to do when I had surgery on my left knee and couldn't bend it: learn how to shift without using the clutch. Not something I would recomend, but it's a nice talent to have.
Did your gearbox survive this?!!?
(If so so what's the trick?
)No clutch shifting...was told by a friend a couple of years back that if you do it fast enough it should be no problem.
Ofcourse he had a really old beat up Volkswagen so his gearbox was probably wasted anyway..
#8
Philip Lee KK
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- 357 posts
- Joined: April 01
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Posted 27 September 2001 - 03:50
Originally posted by Indy2
Did your gearbox survive this?!!?
(If so so what's the trick?
No clutch shifting...was told by a friend a couple of years back that if you do it fast enough it should be no problem.
Ofcourse he had a really old beat up Volkswagen so his gearbox was probably wasted anyway..
As long was the enginee speed matches the drive-train speed, there's shouldn't be a problem changing without clutch.
nobody use clutch for upshifts in race cars anyway.
#9
Schummy
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Posted 27 September 2001 - 11:50
Of course, you can change gears without clutch in Gran Turismo (Playstation) 
BTW, I've tried left foot braking in GT but I find it pretty rough
BTW, I've tried left foot braking in GT but I find it pretty rough
#10
scarbs
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- 743 posts
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Posted 27 September 2001 - 15:17
I put a comment in the text about corners needing gearchanges or not. In if a car has a dcent gearbox and accurate linkage, then as I said, in higher gears going from 6th down to about 3rd can be done clutchless, this needs some commitment, you need to be braking enough to unload the box, slip the lever out of the gear and apply firm pressure to lever against the next gear, now blip the throttle and the gear should slip in, if not keep blipping the thottle and pressing the lever, its all down to timing. Synchromesh boxes can allow smooth cluthless changes, dog boxes (like on my old Mini cooper) are easier but more harsh, of course Bike engined cars ( or just bikes...) are dead easy as they have sequential selectors and dog ring engagement, they hardly need clutch up or down the box.
