hi,
i want to ask some questions about no TC driving.

- when i get back on the throttle at the exit from a corner , i know that i have to do it the gently. my question is: how do i shift up?
i have seen some drivers that shift up a bit before the max RPM to avoid wheelspin. is that a faster way , or should i accelarate without shifting until the rev limit?


thanks

what car are you driving?

He is driving XFG i guess as he's demo racer.

Depends how you feel the car, everyone suits their own gearing way what works out best. You can try different ways.

Essentially, you should shift just before the Redline. At this point, it should be reaching its max HP and Torque, so its pointless ringing the most revs out of it, as your torque would be trailing off. Ofcourse, this depends on the Circumstance and the cars individual Powerband. For example, if your going up a steep hill and reaching the Rev Limit, it would most likely be best just to keep the revs high and change up when you reach the hills peak, instead of changing up and losing ground due to the revs being too low and the engine not producing enough power/torque.

As for wheel spin, you shouldn't need to worry about wheelspin after first gear, as the XFG and XRG dont have enough power to enduce wheelspin at that gear, and the FBM is running slicks, so theres no need to worry about wheelspin. If however, you are worried about wheelspinning on corner exits (like T1 on blackwood) then you could either practice coming out of it cleanly, or shift upto 2nd to lower your revs and reduce the threat of wheelspin. You may actually end up losing more ground compared to going round it smoothly in first however.

Quote from Kristjan.J :

He is driving XFG i guess as he's demo racer.

Depends how you feel the car, everyone suits their own gearing way what works out best. You can try different ways.

D-----------------Bag..

I would assume he means the XRG or FBM as the XFG is not rwd.

It shouldn't be a problem going around t1 in second gear. I've been doing it for a while in second gear... (default_XRG setup). It is actually easier. And what I've found is that sometimes I am at the redline, and my wheels aren't spinning enough. Because of this, I had to play around with my 2nd gear indiv. gear ratio.

However, the XRG is a good car to drive around BL1 with... that's for sure!

dont forget , i am not using lfs only. i also use rfactor and stcc.
anyway. thanks for helping

In LFS, shift when the red light comes on. There are two exceptions:
- if the driven wheels spin too much, short shift
- if you're really close to a braking zone, stretch the gear

Quote from AjRose :

D-----------------Bag..

I would assume he means the XRG or FBM as the XFG is not rwd.

Ye i am one, im tired and mixed it up somehow

Quote from Kristjan.J :

Ye i am one, im tired and mixed it up somehow

"Im booooooooooooooooooooooooooooooooorrrrrrrrrrrrrrrrrred"

Your other favourite quote

You always want to select the gear that allows the most torque out of the corner. A good guide for doing this is to make sure that you are not shifting before you reach the track-out point. Another guide is to use the highest ratio possible, while still being able to get wheelspin. The XRG isn't that torquey, so it's not really an issue - to get serious wheelspin when the car is set you kinda have to be high up in the rev range and if you're that high then you're definitely shifting before the track out. It all depends on when the torque comes in, and how many revs the engine can do. You want torque at the apex, horsepower on the straight.

As for when to shift, you want to shift after peak horsepower. The reason for this is simple average math. If the engine is producing 200 horsepower at the peak of 10,000, but is still producing 190 horsepower at 10,500, then by all means, rev that sucker all the way up there. Because when you shift, depending on the gearing and the engine, you'll drop 1,500 to 2,000 RPM and depending on how the engine delivers the horsepower you might be down to anywhere between 150 to 170 horsepower once you change gears.

So as a practical example, lets say we have 200 peak horsepower at 10,000 RPM and each shift from 3rd to 4th takes us down 2,000 RPM.

Through 4th gear:

*shift at peak horsepower 10k RPM* 8k RPM 170 HP --> 8.5k RPM 180 HP --> 9k RPM 190 HP --> 9.5k RPM 195 HP --> 10k RPM 200 HP *shift to 5th*

Horsepower average through the ratio: 187 HP

Now lets try shifting 500 RPM later into 4th gear with these numbers:

*Shift after peak horsepower at 10,500 RPM* 8.5k RPM 180 HP --> 9k RPM 190 HP --> 9.5k RPM 195 HP --> 10k RPM 200 HP --> 10.5k RPM 190 HP *shift to 5th*

Horsepower average through the ratio: 191 HP

Of course it depends how much the horsepower drops off, but in most cars going 200 RPM past peak horsepower is a good bet.

In my racecar, with it geared for 150mph, I have to shift between 7040 and 7120 (depending on which gear). Peak power is at 6500ish, so that's around 500-600rpm after peak power.

I would agree with Mad's 200rpm suggestion, but expand it to 200-500rpm depending on how it feels, unless you have access to a torque curve (ideally at the wheels).

Quote from tristancliffe :

In my racecar, with it geared for 150mph, I have to shift between 7040 and 7120 (depending on which gear). Peak power is at 6500ish, so that's around 500-600rpm after peak power.

I would agree with Mad's 200rpm suggestion, but expand it to 200-500rpm depending on how it feels, unless you have access to a torque curve (ideally at the wheels).

in which racing series are you?

It's called Monoposto (italian for Single Seater), which is a championship in the UK for single seaters between 5 and 30 years old, with classes for different engine sizes (1000, 1400, 1600, 1800 and 2000cc). My class is mostly made up of 8 - 10 year old F3 Dallaras.

http://www.dallara398.com/info/carspec

While we're on it, when I drive the BF1 I prefer to drive without TC. But how should one shift when going out of the corners at for instance a South City Track? I try to to smoothly press the accelerator until max revs in low gears (gears 1,2,3) since when going full throttle and revs coming into the yellow/red band there is just wheelspin. Especially when still cornering a little.

Would it be better to just shift up in lower revs when power isn't that high because you don't need it/can't put it on the tarmac?

Sidequestion, IRL F1, why do they have so many gears if you'll have wheelspin in 2nd/3rd gear? To save the clutch?

1. Make top gear long enough so that at the end of the fastest straight you are just after peak power, but no hitting the rev limiter if/when you get a slipstream.

2. Make 1st gear short enough so that you can start quickly without destroying your clutch, without bogging down, and without getting silly amounts of wheelspin.

3. Make the intermediate gears so that you can drive through corners in the powerband.

If you are suffering wheelspin out of corners that your throttle control can't cope with, then either lengthen that gear or use the next gear up. Ideally you want to just be traction limited out of the corners. Any more power/torque at the wheels will just be wasted as wheelspin, and less will just make you slow.

Chances are you won't be able to get the gearing so lovely that every corner exit is just traction limited, and you'll have to choose which corner to make the biggest sacrifices - only the stopwatch can tell you if you've made the right calls.

In F1 they'll set 2nd gear long enough that in the slowest corners they can still get on the throttle quite hard without too much wheelspin. This is probably aided by different throttle maps for different drivers, and clever ECU control within the limitations of the standard ECU.

And, of course, the whole topic is more complex than this post can do justice, but essentially it boils down to management of wheel torque, either via gearing, gear choice or throttle (or differentials, or anti-squat, or toe, or damping...........)

Edit: Yes, short shifting is a valid technique. You see it happening in F1 every lap.

thanks for the answer.
you really helped me

Quote from stry90dis :

Sidequestion, IRL F1, why do they have so many gears if you'll have wheelspin in 2nd/3rd gear? To save the clutch?

Irl the tires are better then we get in LFS Irl F1 drivers apply a lot of throttle at rather slow speeds(2nd/3rd gear) in lfs it is bit too much on/off.. no power dam slow... just a bit more power crash!

Although i still like the bf1 most driving without tc, i just think it is just a bit too demanding in lfs on corner exit. F1 tyres have great grip! In straight line, the go full throttle in 2nd gear, in 1st they already go way over 100km/h

Other reason they have so many gears, the penalty for changing gear is very low, a gear changes takes less then 0,10 sec and some reports say gearshifts takes less then 0,04 sec.
This site: http://www.f1network.net/main/s107/st97040.htm claims gearshifts takes 25-30 milliseconds (0,025 - 0,030 seconds)
In 2007 seamless-shif boxes were introduced, meaning no power is lost while shifting.

Quote from stry90dis :

Sidequestion, IRL F1, why do they have so many gears if you'll have wheelspin in 2nd/3rd gear? To save the clutch?

To split the torque. The more gears you have the more you'll be "on the pipe" as you accelerate at full capacity. How many depends on the engine and the car. In another 10 years we'll probably be seeing 8 gears as standard on F1 cars and 7 on lower Formulae, since they'll just get lighter and more powerful and have more stick.

Ok, let's see if i can explain myself briefly...

I find it easier to maintain a drift by keeping a gear rather than upshifting.
My theory is that in the lower gear you are probably close or at the torque
peak, so after that it falls off, a good safety net imo. By giving constant
inputs, the car should straighten itself out using the falling torque. Of
course, some cars peak at redline so it's not always viable.

By upshifting sooner, not only are you disturbing the already delicate grip
(we are trying to drive at the limit here), you are also increasing the
potential speed difference between the road and the tires. One bad
throttle move and the tires can suddenly spin 10mph faster, making the
car slide even more. This seems to apply more to LFS than in real life.
Something to do with the infamous tire code. Irl, most tires have more
elasticity, they can take a jerkin' and keep on grippin'.

Certain conditions are ideal to use upshifting, like a downhill chicane (it
helps you out run the slide) while any uphill stuff would surely make
upshifting an exercise in wasted energy. Basically, i'd say, if you are
already sliding, don't upshift, if you are confident about the grip in the
next gear, upshift. Ideally you want to be constantly on the verge of
sliding/spinning. Only trying it out will tell you if you'll have the traction
or go sliding into the 'pit of no return'

Like any driving techniques, it's about knowing where to use it.

There, i knew i couldn't be brief.