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RWD newbie, FZR handling/setup question:
OK, encouraged by a recent run of good form in the open-wheelers, I decided it was time to try the RWD sports cars again. I still have nightmares about the XR GT and GTT from the demo, and since I'd been having more luck with slicks and downforce, decided to try to learn the FZR by lapping Blackwood until I can keep it on the road. It's going... slowly (1:13s) but steadily improving, but I have a couple of issues with the car's handling and I'm not sure if it's normal or due to my setup:

1) Once I start putting a bit of throttle on to carry me through a corner, the car immediately understeers. It soon recovers and returns to the normal line again, but just that brief understeer sends me a bit wide and I have to correct.

2) When this happens I instinctively release the throttle, which seems to cause the car to suddenly oversteer and it becomes difficult (for me) to recover.

Is this a natural result of weight transfer from the front to the back of the car, and vice-versa? If so, would the only way to improve matters be to stiffen the suspension?

Or could it be something to do with body roll? It seems that tweaking the ARBs does have an effect (I started with them both at 25 and I'm sure the coast oversteer was much more pronounced).

I've got the power diff. set to 65% - could that be causing it to lock when I first apply a little bit of power during a turn and resulting in the car plowing?

Should I just stop worrying about it, learn to compensate for it and stop bothering you all?

I've attached the setup below if anyone wants to try running it to see what I mean. To be honest I could get used to the lift-off oversteer because it's handy sometimes, but the brief power-down understeer is really messing with my head and making me want to not like the oversteer I get when trying to correct it.
i havent really tried the fzr yet after i got fed up with this kind of typical mid-engine behaviour you describe but from what i can tell its the usual problem with heavy mid-engine cars that they either understeer madly once all the weight is on the rear tyres or spin way too easy since they have no weight at the ends of the chassis to slow down the spins
Its all down to the differential.

Whats happening is that the power-side differential setting is giving you understeer with power application, but the coast-side is set so you get lift off oversteer.
Try lowering the power-side lock a little bit to reduce the understeer and increasing the coast-lock a little bit to reduce the lift-off oversteer.

Do it in small steps though as diffs are a bit funny and can start doing the opposite of what you expect if you go too far one way.
I know the behaviour you're talking about and I think the tyre pressures may also add to that behaviour, as in the FZR you have a pretty high tyre pressure in the rears and low on the fronts (making the fronts "less responsive"). Try to raise the front pressure a bit, maybe it helps, but I'm no FZR expert (I prefer the XRR ).
I mostly drive the FZR. What fixed this for me was actually increasing the power side diff. Don't remember what I'm using but I think it's fully up at 80%. If the back is stepping out too much when you release the throttle, then increase the coast side diff too. If you tinker with those a bit you can get it to drive quite nicely at part throttle and off throttle.
The cars with a heavy arse certainly need a high coast lock setting. High power lock depends on how powerful the car is. The GTR cars do need the most locked diffs of all the cars in LFS.

Obviously the car balance set by the springs/ARBs will still have an effect (though the high the coast locking, the more understeer you get - which may be cancelling out the oversteer elsewhere in your set).
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(thisnameistaken) DELETED by thisnameistaken
Quote from thisnameistaken :Shotglass - your explanation does seem to make a lot of sense, it does feel a bit like it's rotating around the middle, rather than being anchored at one end. Is this why the XR seems to oversteer so readily - because it's light and most of the weight is at the front?

the xrr is pretty well balanced in terms of weight distribution but is a little heavier on the front end so the front wont loose traction under accel as much as the fzr does ... so i guess the combination of good frontal traction and a big laggy and unpredictable turbo will make the rear step out a lot easier and a lot less controllable than with the fzr (ill have to admit that i didnt have time to try both cars enough to really know what im talking about though)

Quote :I had thought maybe the tyre pressures all around might be too low, causing the car to not respond quickly enough to throttle when turning, so I'll try increasing those too, but I don't really know what sort of numbers represent sensible pressures so I'm a bit sketchy about changing them. I'll have to learn I suppose.

well from my understanding of how the weight shift on mid engine cars influences the handling theres little you can do about the exit understeer except for increasing the diffs powerlock so you can steer the car with your right foot (and you might want to try to bias the cars "weight" more to the front by raising the front wing)

and not using a high nose setup might also help
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(thisnameistaken) DELETED by thisnameistaken
About choosing tyre pressures, to a certain extent you're limited to whatever keeps the tyres warm without frying them. Adjust the pressure until both front and rear tyres are just above optimum temperature (that way when the tread thins the temps don't get too low), then maybe increase the pressure at one end to alter the balance if you want.

Note that guide doesn't really apply to the FWD cars, otherwise you'll be close to minimum pressure at the rear to try and get some heat into them. In that case start low then just increase until the handling sharpens up enough (the rear end will be wallowy and prone to excess sliding if the pressure are too low at the rear).
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(thisnameistaken) DELETED by thisnameistaken
My fave GTR car is the FZR, but I must admit I haven't touched it in a few weeks.

My style is very much an early turn in, but a 'standard' apex. I'm very smooth on the way in, and my gradual turn in helps resist the turn in understeer. Nearer the apex I find I need to overlap the brake and throttle a bit, and then floor it. In my experience the car works best with about 5 degrees of power oversteer (maintainable with full power and neutral steering).

For fast corners it seems to be the opposite. Fling it into the corners and hope it sticks. Because the engine is in the back I find it preferable to have a smidgen (and I mean just a smidgen) of understeer in the fast ones if I cannot get just the right amount of oversteer.

It seems to be a car that likes to be thrown around (as long as you don't let that engine act as a pendulum), or caressed into corners. Half measures just upset it, so commit yourself to one style.

I can't remember setup specifics, and it's too late to look, but I think I had 50% power, 60% coast diff settings as my base setting. Wings are not very fine tunable, so get a value that seems about right, and get the aero balance close enough. But don't expect to be able to make subtle balance changes with the wings. One click too far = terrible oversteer, one too little = terrible understeer.
Not sure on ARB's, springs or dampers. As I said, I'll check tomorrow.

Add me to MSN, and I'll send you a setup or two tomorrow (or post them here).
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(thisnameistaken) DELETED by thisnameistaken
Quote from thisnameistaken :Turn-in understeer? How did you get it to do that? With mine I also have to be smooth, but to avoid oversteer on turn-in. Although I find I'm flicking the wheel a bit further once I reach the apex to get the oversteer happening, then putting the throttle down to maintain it.

Perhaps it's just my setups then, but I've found that if I turn in at the standard point (where most people turn in) I end up with understeer. If I turn in quite a long way early, only gradually, as I brake, and then trail brake deep into the corner it stops this. As I say it might be my setups, or just my imagination :S
Quote from thisnameistaken :Another newbie question if you have the patience: I see a lot of mention of <x> degrees of oversteer - is estimating this angle something that just comes with experience? For me, it's still "Nice oversteer" or "Oops oversteer", and I've no real clue (in terms of measurements) how far the car rotates before I get into tankslapper territory.

Well, I mean the angle between where your going and where you are facing. The overall slip angle if you like. But in your method (which isn't necessarily any worse than mine, and better in some respects like simplicity of understanding) just keep the car in the 'Nice oversteer' area. In that area you should be able to use zero steering, full throttle, and the car turns just enough to get round the corner in the fastest way. It won't work on every flat out curve, because they are not all the same length and radius. Having the car stay in 'Nice Oversteer' all the time is the quickest way.
Quote from thisnameistaken :Not actually tried any fast corners yet, I've only driven it around Blackwood, but I was planning on trying to set it up for Westhill next so thanks for the advice.

Shudders at the thought of Westhill setups... I hate testing there. I find it so hard to get a balance between corner and straight speed, and handling prowess through each of the turns. Maybe I'll venture back and give it a go soon though.
Quote from thisnameistaken :I don't have any IM clients installed (forums cause me to procrastinate way too much as it is, so I've had to deny myself instant messaging), but if you're OK posting them to the forum I'd be dead chuffed, cheers Tristan

No problem. I'll stick them on tonight after work. Or perhaps find you online and we can 'test' together
Arrgghhh, nearly forgot about this thread. No one posted in it, so it didna show up in my New Posts check

Anyway, I'll post some of them. I never got round to testing them, but I think these are some of the better (best) ones I have. Give em a try

By the way, these might be from other people, but my odd naming convention means that I 'forget' who they are from. So don't blame me if they are rubbish
Attached files
FZ50 GTR_TC KY1.set - 132 B - 1450 views
FZ50 GTR_TC BL1.set - 132 B - 1052 views
FZ50 GTR_TC KY3.set - 132 B - 1032 views
FZ50 GTR_TC SO5.set - 132 B - 875 views
Quote from tristancliffe :Perhaps it's just my setups then, but I've found that if I turn in at the standard point (where most people turn in) I end up with understeer. If I turn in quite a long way early, only gradually, as I brake, and then trail brake deep into the corner it stops this. As I say it might be my setups, or just my imagination :S

that almost sounds like youre drifting
9hides9
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(thisnameistaken) DELETED by thisnameistaken
I can't really help you much with setup stuff but I think with RWD and in particular a rear engined one like the FZR throttle control becomes very important. On throttle understeer will transition into oversteer with the right use of the throttle, whether it be just giving it more throttle or momentarily lifting before reapplying to get the nose to turn in.
In the FZR you will need to use some corner exit oversteer on many corners but of course there's the ever present danger of overheating the rear tyres.
I haven't driven Blackwood since S2 was released but on Wednesday night I took part in a 45 lapper at Westhill in the FZR so I'll attach my set. For me at least I found it fairly predictable in it's behaviour and I could do 22-23 laps on R2's at a consistent 1:34-35 pace. The original is actually by king13 which I got from inferno and modified a bit for endurance. This might help you just to get some decent seat time in the car, maybe do 10 lap stints and try not to get the rears over about 90-92 degrees C. If you think it will help I can link you to the race replay.
Attached files
FZ50 GTR_we1test.set - 132 B - 997 views

FGED GREDG RDFGDR GSFDG