After struggling to get below 1:35 at Blackwood in XFG (stop laughing!), I downloaded some 1:33.xxx hotlaps and analysed the data in pursuit of an excuse.

I noticed that apart from braking very suddenly (and late) they were holding the brakes full-on and well in towards the apex - and this going downhill too. From driving other sims, I'd have expected that you'd either plough straight on or lose the rear end turning in like that unless you trail braked properly. My body actually rebels against turning in with the brakes full on as it feels so wrong. Surely this isn't realistic?

Also, the XRG, despite having little power, power-over-steers on exit like an AC Cobra in GTL, and then wags it's rear end around like there's an invisible caravan on the back. There isn't is there?

its all about setups, their braking probably is not set to near lock up, it is prob toned down. and their tires are probably perfectly heated. also, the suspension has a lot to do with this; the stiffness, and damping is very important, and anti-roll and ride height is kinda important. camber and tire pressure is also a good place to get your grip, and corner stradegy.

hope i helped

http://www.vehicle-analyser.com/

This might help you develop faster and more stable setups.

Quick tip. Try adjusting brake balance and max brake force and rear arb.

Yup. I think the quick setups are countering FWD understeer with a lot of rear stiffness to increase load transfer at the rear and cause oversteer. It works in real life too - see how many FWD cars pick up the inside rear wheel.

Don't really understand the logic here (which doesn't mean it's wrong). Surely there's a traction budget at each end whether the car is oversteery or understeery (or balanced). If you exceed it, you'll either lose grip at the front or the rear, (or both and four wheel drift). You could even alter it with left-foot braking and throttle. I recognise the XFG allows you to brake fully without locking up so there's a bit of scope for turning in under braking, but if you're turning in that far under braking, I'd have thought something ought to let go somewhere. Apart from anything, it's inefficient braking if you're not on the threshold in a straight line.

But anyway, I've thought of completely different excuse now, so i'll pursue that one a bit and see if it makes me any faster, and then come back and complain about the physics again if that doesn't work.

Tried increasing the braking strength and seeing if that causes the problem(s) you expect?

I didn't realise you could do that. It will obviously lockup then. But using either the 'race' setup or a hotlapper's, it would need massive front brake bias to lock the fronts first. Seems odd?

And it still won't 'steer with with the brake' under trail braking as in GTL, RBR, or Netkar pro etc. Experimenting with the XRG, I can't get the front to bite and turn in. Seems fastest to throw it into the first corner. Whereas I like to brake straight then trail brake in. Perhaps I'm too 'safe' due to ISI games. But that's the way they teach it in RL isn't it?

Anyway, got down to 1:34.80 just by using sequential (with stick and clutch pedal) instead of H-shifter. Also just realized I don't know what the fast guys I've seen are doing; they're obviously left foot braking, but no autoclutch. Do they use a button instead of pedal to clutch?

It also depends on differencial and suspension settings. Try open diff at the front, it will turn in much better... oh and most hotlap/race setups are using locked diffs, which create huge undesteer when You are going off the throttle, and massive oversteer when You are accelerating at the exit of the corner .

Edit: Here's mine road going setup , try it .

As logitekg25 already said, brake force is usually limited setupwise so the tires won't lock in almost any condition.
As for the corner exit oversteer while increasing the throttle, (Byku allready said this) it's just the violent transition from push understeer to "pull" oversteer that the locked diff produces while going from braking to accelerating not in a smooth or optimal way according to the car's full traction capabilities. (e.g. If you drive the XFG utilizing the full front tire's limit, it most likely won't oversteer when you start accelerating)

Quote from tristancliffe :

Yup. I think the quick setups are countering FWD understeer with a lot of rear stiffness to increase load transfer at the rear and cause oversteer. It works in real life too - see how many FWD cars pick up the inside rear wheel.

Actualy if you take a look at LFS FWD setups you will see exactly the oposite.
For the reasons I have allready mentioned here , here , here and in other posts that I don't bother posting here because they are all referring to the same problem described in more words.

Quote from DaveJ :

But that's the way they teach it in RL isn't it?

Anyway, got down to 1:34.80 just by using sequential (with stick and clutch pedal) instead of H-shifter. Also just realized I don't know what the fast guys I've seen are doing; they're obviously left foot braking, but no autoclutch. Do they use a button instead of pedal to clutch?

yes that is what they teach in real life, and i would stick to H-pattern, because it is funner, and better to use that than sequential. the people who you say left foot brake, probably just heel toe like me...i heel toe a LOT!! double clutching is also a good idea so you do not get a sudden jolt forward when slowing down, so yuo keep all of your traction

lets hope i made sense!

Those 'here' links have scrambled my brain cell. Too complicated for me. Although, I did notice myself that softening the front springs and reducing ARB didn't seem to reduce understeer, and gave up and went back to a hotlapper's set ("Sarfa"- 1:33.110) - someone seemed to be saying that...I think.

Just to be clear, the power oversteer problem was with XRG.

logitekg25 (how yer share's doing btw? ), I only tried the sequential to see what difference it made over H-shifter, and will surely return to 'proper driving'..honest! These guys *are* definitely left-foot braking as far as I can see - at the end of a straight braking before they're off the throttle. I always heel-and-toe myself as you can't drive GTL without a blip or you'll swop ends most of the time.

Quote from DaveJ :

(how yer share's doing btw? )

? i have no idea what you are talking about, but if you remind me, then i will probably figure it out

LogitekG25 - the clue's in your name!

Anyway, just occurred to me, I haven't got a complete Holapper's set, only the details listed in LFS Replay Analyser. So all those differential settings people are talking about might indeed be making a difference how they behave for me.

You can find many of those WR or similar setups in these two sites.

http://www.setupgrid.net/
http://setupfield.teaminferno.hu/

Quote from DaveJ :

Don't really understand the logic here (which doesn't mean it's wrong). Surely there's a traction budget at each end whether the car is oversteery or understeery (or balanced). If you exceed it, you'll either lose grip at the front or the rear, (or both and four wheel drift). You could even alter it with left-foot braking and throttle. I recognise the XFG allows you to brake fully without locking up so there's a bit of scope for turning in under braking, but if you're turning in that far under braking, I'd have thought something ought to let go somewhere. Apart from anything, it's inefficient braking if you're not on the threshold in a straight line.

But anyway, I've thought of completely different excuse now, so i'll pursue that one a bit and see if it makes me any faster, and then come back and complain about the physics again if that doesn't work.

All of what you say there is true and LFS physics support it all. What does happen though is that there are things you can do with the nearly infinite setup possibilities in LFS to counteract a lot of those things. Yes, it is still a compromise, but these hot lappers make everything extreme. They have to in order to make the times that they do.

Not to mention a lot of the hot lap guys can do things with those cars that look impossible. If you try it, you won't make it work, trust me. So a lot of what you are seeing is down to the driver.

You are better off getting some replays from somebody who is practicing for a race and doing tire tests or something. Then you can see a more reasonable setup and more normal driving.

I trail brake, but i have to carefully modulate the brake in order to do so. You will turn the car around if you are too aggressive with it. You'll find that with a reasonable setup, LFS will feel very realistic and predictable, if not exactly like ISI based sims.

Quote from DaveJ :

Also, the XRG, despite having little power, power-over-steers on exit like an AC Cobra in GTL, and then wags it's rear end around like there's an invisible caravan on the back.

I know. That feels so unrealistic

Didn’t notice that comment on the first post earlier. (talking about careful reading eh? )

Do you care posting the setup you are using? Even with default, which suffers from instability during lateral weight transfers as most LFS default setups do, I can’t see what you are referring to.
Can you separate faint oversteer from power oversteer? The XRG shows hardly any power overtseer even in second gear. Only when exceeding it’s lateral acceleration limits it will loose the back end under full throttle and will continue sliding mainly because of it’s momentum and not because of it’s power.

If the AC Cobra in GTL shows that little power oversteer and is affected much less by weight transfers, then the GTL’s model is unrealistically easy to drive…

Quote from bmwracer67 :

I know. That feels so unrealistic

Mate, it's ALL ABOUT THE SETUP. I don't know how real life fwd cars with locked diffs behave, but with open, or with lsd, they are pretty close.

Since shortly I make my sets with a LOT more braking power (20% more).
This will result in faster tyre wear, but if done correctly, you can race more with it.
The set without more braking power will only be fast if you are not behind anyone, but who wants to hotlap on multiplayer?

Quote from DaveJ :

LogitekG25 - the clue's in your name!

i figured that, but i have no idea, when i probably should

He means because of your name, you may have money invested in logitek, hence the share comment?

ooo, duh, now i feel stupid i have a g25, and a attack 3 joystick, among other small stuff(keyboard mouse) and i guess thats good

Quote from kaynd :

Can you separate faint oversteer from power oversteer?

Yes, quite right, it's not power oversteer it's momentum.Sorry about that. But it slops around like there's a trailer on the back. And only takes a little bit of throttle when you think you've gathered it in, and it's off again.

Thanks for the setups link. I tried one, and straight away it was faster in the bits I couldn't improve on before. Haven't got it under control yet, but just did a messy 1:34.58. Very odd setup though, front tyres had massive temperature difference between inside and outside of each tyre. Surely too much camber. I actually think maybe those fast times are do-able baring in mind how much later those guys brake. You're definitely on the money about the locked diff though. If you ease off the brake and get straight on the power, it turns you in.

But it also feels in places like I'm disregarding everything I knew about driving. I can't believe I'll get away with something, try it, and it's faster. There's a lack of twitchiness and danger IMO. You can throw it into the first bend and it either understeers or wallows or slides neatly around but it doesn't ever bite you. I can't believe it would be that easy and progressive - like holding the XRG in a powerslide is. Anyone could do it first time in RL if it was that easy. Surely not.

The ISI stuff is almost impossible when it *unexpectedly* lets go, but LFS seems to be the other extreme. Too gradual and smooth in a slide (based on the demo anyway). Perhaps that's some of the problem with XRG: it's sliding but it's so gradual and well behaved I don't even know it's happening!

Hey, Logitekg25, yeah...with your enthusiasm for the H-shifter and name.

A badly setup car in LFS can have a fair bit of snap, I think it's our well polished setups (we've had 6 years of tinkering on the XRG!) combined with perhaps a slightly forgiving tyre model that give this feel. Until I've taken a RWD car to a track myself, I'll have to pass any personal judgement - my Mondeo is only good for teaching me about understeer.