The online racing simulator
#1 - Samor
clutch + sequential shifting on h-shifter cars
I have gotten myself a Thrustmaster RGT wheel, which has has a sequential shifter, and a clutch pedal. For the sequential shifter cars, I have the clutch enabled.

I also tried this with the H-shifter cars, but I found this to be quite difficult when having to downshift multiple gears for corners.

Is it good practice to try and learn it? Or is it increasingly difficult because one isn't really supposed to drive like that?
Using the clutch for the H-shift cars is something you'll have to get used to. If you had an H-shifter you would have to press the clutch every shift.

However, when down shifting you could just hold the clutch down and cycle through the gears until you get to the correct gear you need to be in for the corner, then just rev match once. The problem with this is that you could shorten your break distance by engaging each gear as you down shift.

Whether it is good practice or not is up to the driver, some racers (including me) still heel & toe in the XRR and FXR, even though you don't have to use the clutch on down shifts.
#3 - ajp71
I have a clutch + sequential setup and find that heel and toeing is no problem, you'll soon get used to it.
#4 - Samor
hm well, one shift is not a problem, going multiple gears down is where it feels awkward (because you don't have to cycle through gears with an H-shifter)
...although I guess if you use the XRR or FXR and use the clutch, one'd still be doing the same thing.
#5 - ajp71
Quote from Samor :hm well, one shift is not a problem, going multiple gears down is where it feels awkward (because you don't have to cycle through gears with an H-shifter)
...although I guess if you use the XRR or FXR and use the clutch, one'd still be doing the same thing.

Just take your shifts slower, let the clutch out and blip the throttle between each shift and make less gear shifts.
If you can shorten the braking distance by engine braking, the car is set up wrong.

Brake balance on a race car is set up to get the most out of both the rear and front wheel's traction at all times, adding a braking force to the rear wheels isn't going to magicaly give them more grip.

Heel-toe is intended to keep the car in gear and balanced at all times, it actualy reduces engine braking. This way if you need power it's ready at all times. All you are doing is driving an H-pattern the same way you would drive a sequential.
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(Samor) DELETED by Samor : not so relevant.
Then it is just my setup, I don't like the engine "boging" down when enter a corner, so I set the rear bias a bit lower and use the engine to get the rest of those rear tires while breaking. I blip the throttle so that the rear tire don't lock up aka rev matching. As long as I don't ride the throttle as I down shift, I still get the compression breaking.

Edit: Like I said its a driver preference, and you do as you like. On another note I trail-brake into some corners, if the bias is too rear dependent, then the car would over steer into those corners that I trail-brake into.
Quote from DragonCommando :If you can shorten the braking distance by engine braking, the car is set up wrong.

While I agree on principle, this is not necessarily true in LFS (might change once brake heating and fade are implemented?)

Threshold braking is something relatively hard to pull off consistently when you're lacking g forces and have a travel-based brake pedal. Usually a track also has some corners where the track conditions don't allow full braking force (think South City), and since to finish first you first have to finish, removing the risk factor of constantly locked up wheels alone gives you a considerable advantage on longer races.

The engine brake is then basically an extra brake that you can apply depending on what the track conditions allow. Additionally to that, it can act as tool to dynamically alter the brake balance per corner, since it only brakes the driven wheels.
#9 - Samor
maybe a weird question, but completing a shift while keeping the brake pedal depressed seems to be a bad thing to do, no?
That is a weird question How else would you downshift for a turn?
Quote from Technique :That is a weird question How else would you downshift for a turn?

you could brake, then shift?
I'm asking because if I downshift in the sequential cars without using the clutch, while braking, the turbo makes quite a weird sound. Or is it supposed to do that?

I could make a replay if its not clear what I mean...
Quote from DragonCommando :If you can shorten the braking distance by engine braking, the car is set up wrong.

Brake balance on a race car is set up to get the most out of both the rear and front wheel's traction at all times, adding a braking force to the rear wheels isn't going to magicaly give them more grip.

Heel-toe is intended to keep the car in gear and balanced at all times, it actualy reduces engine braking. This way if you need power it's ready at all times. All you are doing is driving an H-pattern the same way you would drive a sequential.

Well lets not start that whole debate again, regardless of the fact that nearly every respected figure in motorsport would champion the conventional sequential downshifting of gears whilst decelerating approach

If you've ever driven a road car on a track or even hard on the road on DOT4 you'll know what brake fade is and know that it isn't desirable and anything to help reduce the load on the brakes without reducing stopping power is desirable.

A side from the issue of brake fade, in short runs with racing brakes and in LFS heel and toeing still has an advantage over going down through a sequential 'box where it's very easy to go through too many gears too fast and not blip the throttle correctly as you do so resulting in too much engine braking and a rear end lock up and loss of control under braking. With an H-pattern 'box and clutch usage the action of changing down a gear is more effort and I've never heard of someone accidentally making two distinct gear shifts by mistake with an H-pattern.
Quote from Samor :you could brake, then shift?
I'm asking because if I downshift in the sequential cars without using the clutch, while braking, the turbo makes quite a weird sound. Or is it supposed to do that?

I could make a replay if its not clear what I mean...

Not sure about the "weird sound". I haven't played LFS in a while and I've only driven one GTR car for a couple of days (i might have used autoclutch too).

But downshifting after braking is a bad idea. After braking you should be entering the turn or already in the turn (if trailbraking). You don't want to be downshifting at that point.
Quote from ajp71 :...LFS heel and toeing still has an advantage over going down through a sequential 'box where it's very easy to go through too many gears too fast and not blip the throttle correctly...

I'm not sure how much of an advantage heel/toe actually provides in LFS. How many WR holders/"aliens" in premiere leagues actually heel toe? My guess is not too many - I might be wrong though.
Quote from Technique :I'm not sure how much of an advantage heel/toe actually provides in LFS. How many WR holders/"aliens" in premiere leagues actually heel toe? My guess is not too many - I might be wrong though.

Aliens may be fast and have fun exploiting the flaws of the simulation, but I'm having fun pretending to drive a race car
you also have to remember that engine braking in higher gears is so low it's almost usless. High performance cars are no different than low performance cars in that respect, because the compression doesn't cause braking. They call it compression braking but its actualy the vacuum when the throttle closses that causes the braking effect.
I already explained all that to some people on the forums a while ago. I've driven road vehicles that will put your head into the steering if you let off the throttle to fast in a low gear, and these arn't exactly highly tuned engines with alot of compression.

As I said, heel-toe is not for using the engine to brake, If you ask a driver who does it they will tell you that the time you spend in each gear and the amount of braking you get is so minimal it won't help you any. If you use it to slow down on a fast corner where you don't need the brakes is a different story though. Thats how you save the brakes, not by engine braking in a low speed corner where you downshift 3+ times. The amount of engine braking you get in any gear over 2nd is usless, unless you have more than 10 gears and they are all realy low.

I don't know how LFS simulates engine braking, but if it isn't calculated by vacuum vs. Bore x Stroke it's wrong. A wider bore will mean more engine braking regardless of compression ratio.
Quote from DragonCommando :you also have to remember that engine braking in higher gears is so low it's almost usless. High performance cars are no different than low performance cars in that respect, because the compression doesn't cause braking. They call it compression braking but its actualy the vacuum when the throttle closses that causes the braking effect.

I can happily bring my everyday road car from speed to under 30mph without using the brakes and when I know I need to slow down (junctions, corners etc.) I'll often not touch the brakes except to bring the car to rest from low speed, most of the gentle braking people do from high speed causes a lot of wear and doesn't achieve anything engine braking can't. I can assure you engine braking is effective at high speed in road cars, if it wasn't I may well not be here, following a very dodgey moment as a passenger in a car with no brakes doing well over the ton
#18 - h0tz
BTW, engine braking is mainly caused by friction and inertia and not by compression / vacuum.
Road cars tend to have lower ratios than race cars. I'd still like to see you outbrake someone who has a car set up for racing. You use engine and they use brakes, see who slows down faster. Hell you can use BOTH and they will slow down faster than you on brakes alone. Not because of skill, but because the car is set up better.

The amount of braking you will gain from using both is pointless, like I said, you can use it when you don't need to use the brakes to slow down, but when you want to realy slow down for a corner you will still have to use the brakes. At which point engine braking, and its comparably lower force, is still going to be negligable when you are slowing down with the brakes. Remember, these guys arn't on a sunday drive, they don't have time to leave it in gear for engine braking to have an effect. they usualy spend as much time in gear as they do out during braking, especialy if they double clutch as they heel-toe.

@h0tz
Please don't make me re-write the whole article about engine braking I had to write in the other thread. I'd link to it, but I can't find it either.

Engine braking is caused by the vacuum of the intake system, because the engine needs to speed up and the throttle is closed, vacuum increases, this increases resistance on the piston face when it lowers on the intake stroke.

If you look at engines the way I do, from a completely physical and mechanical sense you will realize that compression is always paired with a power stroke so it can't possibly be compression, it can't be friction because again, there's always a power stroke happening to counteract that. So whats left? Vacuum in the intake causing the pistons to do more work during the intake stroke.

And I won't even get into diesels and engine brakes, because they are very different.
Quote from DragonCommando :Engine braking is caused by the vacuum of the intake system, because the engine needs to speed up and the throttle is closed, vacuum increases, this increases resistance on the piston face when it lowers on the intake stroke.

Its not really having anything to do with the engine needing to speed up. The engine only is speeding up while you rev matchout.

Engine/compression braking comes from atmospheric pressure in the crank case acting on the back of a piston as it tries to pull a vacuum against the closed throttle plate. The engine isn't speeding up, its trying to keep its speed, not accelerate but doing work against the pressure outside of the cylinder draws energy from the rotation of the engine and it slows.

Also, race cars generally do engage each gear going down into a corner, thats why you hear a rev to match each gear as they shift into it. If they weren't putting it into gear and letting the vacuum slow the engine through each gear they wouldn't have to keep rev matching each gear.

Also "Brake balance on a race car is set up to get the most out of both the rear and front wheel's traction at all times, adding a braking force to the rear wheels isn't going to magicaly give them more grip."
Optimal tuning takes this into consideration, thats part of what optimal is.
I don't think you read everything in the thread before posting that.

Also Crank case pressure has nothing to do with engine braking, you will never get a noticable drag because of air moving in the crank or because air pressure is higher in the crank than in the pistons.

Engine braking is caused by vacuum in the intake. When the throttle is closed it's vacuum that keeps the engine from accelerating, there is always vacuum in an intake system, and in the pistons during the intake stroke. When you downshift and close the throttle, this vacuum increases because now the engine HAS to turn at a faster rate regardless of if you rev match or not. Rev matching is to reduce the shock, so the engine is already turning faster, but as soon as you release the throttle and let out the clutch the engine is going to try to slow down. It's vacuum that keeps an engine at idle.

However, race cars shift so quickly when braking that you should not be in a gear long enough to get anything out of engine braking.
#22 - h0tz
Quote : If you look at engines the way I do, from a completely physical and mechanical sense

...well, i study automotive engineering, so i look at it exactly the same way. But again, engine braking is not due to vacuum in the intake system. Usually in trucks (diesels mainly) you have an extra engine retarder, which closes the exhaust-system to generate extra compression or an eddy-current brake.
I am not saying that the vacuum has nothing to do with it, but the main reason for the braking effect is inertia and friction in the hole drivetrain...

Diesel trucks are completely different than cars! damnit I hate it when people are blind to whats right in front of them.

I'll repeat what I've said to at least 20 people already.
Diesel trucks NEED TO HAVE the exhaust brake because they do not have a butterfly valve to create engine braking, friction is overcome by the fact that the engine is always firing on ANY vehicle. Also, try engine braking with the engine off and the throttle wide open, it doesn't happen. But as soon as you close the throttle you will begin to slow down much more than with it open. I've done extensive research into this and have tested it myself on many different types of engines.

Engine braking on a gasoline car is caused by a high vacuum behind the butterfly valve, this causes the engine to have to work harder to "pump" air/fuel into the pistons durring the intake stroke. friction is always overcome by the fact that when one cylinder is on intake another is firing.
The reason your engine slows down when you release the throttle is because the vacuum increases and slows down the engine to a rate that air can come in fast enough for the power stroke to overcome the effort needed to maintain vacuum in the intake without stopping.

Inertia is also a factor in keeping the engine running, thats what the flywheel is for. Thats also why engines don't instantly return to idle when you release the throttle with no load on them, there is enough turning mass to keep the engine at speed for a while, even though there is a vacuum increase. Inertia of the drive train does exactly the opposite of engine braking, its why the engine has LESS of an effect than regular brakes.

The shape of the cylinders effects engine braking alot, if you have a very short stroke with a wide bore, you get more engine braking than if you have a long stroke and a narrow bore. Regardless of displacement
I think LFS needs to implement better engine breaking too.
Quote from DragonCommando :Road cars tend to have lower ratios than race cars. I'd still like to see you outbrake someone who has a car set up for racing. You use engine and they use brakes, see who slows down faster. Hell you can use BOTH and they will slow down faster than you on brakes alone. Not because of skill, but because the car is set up better.

I don't know who said heel & toe is used for engine braking, but when the clutch is engaged, and not in neutral, the effect of the engine slowing down the car is present, if the driver is not equalizing the throttle for their speed.

I definitely agree that no amount of engine breaking can match a perfectly set up break bias, however when trail breaking, in the corners where it is not completely useless, having that rear bias will upset the rear tires while turning. While I don't have my bias set to where both front and rear use maximum grip at the same instant while going straight, the bias is not too far from that either.

My statement about shortening braking distance in my firs post is wrong, as it was based off of the way I set up my baking bias.
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