ICR2 Oversteer

I've spent a little bit of time behind the wheel in ICR2 and I think I'm finally getting the hang of it. My times are getting pretty close to the "World Records" posted here, at least on the tracks where I've practiced. However, time and time again, what does me in is oversteer while powering out of a corner. When I feel the car start to oversteer, I back out of the throttle and steer opposite lock, but the car just keeps on going around. This happens even at speeds less than 40 mph. It seems to happen fairly frequently when I jump on the gas after heavy braking (two-foot brake/gas). One of the worst corners is the turn just before the hairpin at Long Beach. I find I can usually beat the AI cars to the hairpin and take away the inside line this way. I'm sure part of the problem is that the physics model doesn't support wheelspin properly, so you don't hear the engine racing or see the tach jump when the rear wheels break loose. But aside from that, it seems like the cars spin much too easily at low speeds. Any suggestions?

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>Subject: ICR2 Oversteer >Date: 23 Apr 1996 05:48:05 GMT >I've spent a little bit of time behind the wheel in ICR2 and I think I'm >finally getting the hang of it. My times are getting pretty close to the >"World Records" posted here, at least on the tracks where I've practiced. >However, time and time again, what does me in is oversteer while powering >out of a corner. When I feel the car start to oversteer, I back out of the >throttle and steer opposite lock, but the car just keeps on going around. >This happens even at speeds less than 40 mph. It seems to happen fairly >frequently when I jump on the gas after heavy braking (two-foot brake/gas). >One of the worst corners is the turn just before the hairpin at Long Beach. >I find I can usually beat the AI cars to the hairpin and take away the >inside line this way. >I'm sure part of the problem is that the physics model doesn't support >wheelspin properly, so you don't hear the engine racing or see the tach >jump when the rear wheels break loose. But aside from that, it seems like >the cars spin much too easily at low speeds. >Any suggestions?

If you're oversteering right, increase neg. camber on your RR. Vice versa for left. Actually neg. camber for all 4 helps...

I've spent a little bit of time behind the wheel in ICR2 and I think I'm finally getting the hang of it. My times are getting pretty close to the "World Records" posted here, at least on the tracks where I've practiced. However, time and time again, what does me in is oversteer while powering out of a corner. When I feel the car start to oversteer, I back out of the throttle and steer opposite lock, but the car just keeps on going around. This happens even at speeds less than 40 mph. It seems to happen fairly frequently when I jump on the gas after heavy braking (two-foot brake/gas). One of the worst corners is the turn just before the hairpin at Long Beach. I find I can usually beat the AI cars to the hairpin and take away the inside line this way. I'm sure part of the problem is that the physics model doesn't support wheelspin properly, so you don't hear the engine racing or see the tach jump when the rear wheels break loose. But aside from that, it seems like the cars spin much too easily at low speeds. Any suggestions?

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>>However, time and time again, what does me in is oversteer while powering >>out of a corner. When I feel the car start to oversteer, I back out of the >>throttle and steer opposite lock, but the car just keeps on going around. >>This happens even at speeds less than 40 mph. It seems to happen fairly >>frequently when I jump on the gas after heavy braking (two-foot >brake/gas). >If you're oversteering right, increase neg. camber on your RR. Vice versa >for >left. Actually neg. camber for all 4 helps...

I've already added negative camber on all four corners. I'll try a little more. Bear in mind that the car doesn't oversteer under any other circumstances, it actually plows a bit at the moment because if I set it up for neutral steer getting into the corner, the oversteer on exit gets worse. I just find it hard to believe that you can spin a car under those circumstances. The aligning torque on Indy tires is awesome at low speeds, you can tell by how hard it is for the crew to push them with the wheels pointed any direction except straight ahead. I wonder if Papyrus might have left that out of the physics model to reduce the calculations. Dave P.S. Sorry for the double post, I was having NNTP trouble, and someone posted the first message for me.

I too agree that the cars spin much too easily at low speeds; however this may or may not be a bug since Indy cars loose a lot of down force at low speeds. This is due to the fact that the amount of down force generated by the wings has to do with the the speed at which the on coming air hits them. Higher speed means greater down force and lower speed means less down force. Have fun!

There are many causes for that. Cold tires, stiff shock settings in the rear, steering controller type coupled with steering lock size and linear vs non linear steering settings. I use a wheel and pedals so I use linear steering and generally use the LEAST amount of wheel lock that I can get away with. This cuts down on steering sensitivity. I also use lower shock setting in the rear so that it squats and gets more grip. Tire temperature and compound... generally use soft on the road courses but you must get some heat in them or you will spin. Smoothness really counts in ICR2. You must be smooth in your driving, especially on cold tires. Brake bias will effect it also . I'm nothing special but these are basic pointers. Jeff

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>>If you're oversteering right, increase neg. camber on your RR. Vice versa >>for >>left. Actually neg. camber for all 4 helps... >I've already added negative camber on all four corners. I'll try a little >more. Bear in mind that the car doesn't oversteer under any other >circumstances, it actually plows a bit at the moment because if I set it up >for neutral steer getting into the corner, the oversteer on exit gets >worse.

You guys talking about negative camber- some questions. I only ever add it to get my tires even temp across their surface- are you talking about going even beyond that with the neg camber? IOW, are you deliberately getting the temps uneaven across the tire surface? I've never thought of trying that; seemed counterproductive.

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>Subject: Re: ICR2 Oversteer >Date: Thu, 25 Apr 1996 01:04:41 GMT >... >>>If you're oversteering right, increase neg. camber on your RR. Vice versa >>>for >>>left. Actually neg. camber for all 4 helps... >>I've already added negative camber on all four corners. I'll try a little >>more. Bear in mind that the car doesn't oversteer under any other >>circumstances, it actually plows a bit at the moment because if I set it up >>for neutral steer getting into the corner, the oversteer on exit gets >>worse. >You guys talking about negative camber- some questions. I only ever >add it to get my tires even temp across their surface- are you talking >about going even beyond that with the neg camber? IOW, are you >deliberately getting the temps uneaven across the tire surface? I've >never thought of trying that; seemed counterproductive.

It helps with side bite both at the apex and coming out of the corner.

1.) Possibly try to me smoother on the gas (I assume you are using a proportional throttle). 2.) Letting up on the gas is not always a good thing, If you let up to much you will definately cause oversteer. I use this technique all the time in ICR2 to make mid corner corections. How much are you letting up? Increase the tire sound and decrease the car engine sound. This made a *BIG* difference for me.

I don't think it's a model problem in ICR2 here, I think it's setup and driving style. If you've got a persistant problem when lapping, think of the physics of how a car works and figure out what's going on. Adjust your setup and/or driving style to compensate for the problem and try again. You particular problem is that your setup is not quite right for your driving style which causes you a problem. Your driving style then makes this worse and you loose it. (I'm not critisising your driving style here). Your back end is too firm and you've not enough grip. On the exit of a corner you're going on the throttle a little quick for that style set up causing the back end to come out. Try going on the power a little more gently and this will reduce the problem, also try and soften the back end for a bit more grip. Remember you've got a few hundred HP behind you, in 1st or 2nd gear you're going to be spinning the wheels like hell if you floor it, and that's not the fastest way of accelerating anyway - take it easy on the exits. You then say you counter steer and back off a bit - don't, that's the wrong thing to do. Countersteer to correct the slide but DO NOT BACK OFF. Backing off reduced the weight on the rear of the car and so it looses grip - that's the cause of your terminal slide. Keep on the power as you countersteer (even maybe try putting more power on). Jamie ============================================================================== Oracle Park Oracle Office: joshaugh.uk Bittams Lane, Guildford Road Phone : (44) 01932 872020 ext 2298 Chertsey, Surrey, KT16 9RG Fax : (44) 01932 873273 ============================================================================== The opinions expressed here are my own and do not in any way represent Oracle or its policies.

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>You then say you counter steer and back off a bit - don't, that's the wrong >thing to do. Countersteer to correct the slide but DO NOT BACK OFF. Backing >off >reduced the weight on the rear of the car and so it looses grip - that's >the >cause of your terminal slide. Keep on the power as you countersteer (even >maybe >try putting more power on).

I agree that my setup may not suit my driving style, but I'm working on it. The point was that you should be able to save the car at low speeds. I'm willing to agree that at 100+ mph, once the back end starts around, you probably aren't going to be able to save it, though occasionally someone does (I have in ICR2, for instance). I should have been more clear on what I mean by back out of the throttle. If the rear wheels are spinning, applying more throttle isn't going help the situation at all. You need to back out enough to allow them to get traction, while counter-steering to counteract the spin. This does not seem to work for me at low speeds. It may well be that my driving skills are wanting here, but I have done this in a real car (obviously not an Indy car) and it works. Perhaps I'm wrong, but I still l think that those big tires ought to straighten the car out pretty quick at less than 40 mph. At any rate, I've been wrapped up in MP NASCAR since I wrote that, and I probably won't get back to ICR2 until MP ICR comes out. <grin> Dave

Don't take it too harsh, I'm not being critical of you personally, if you're posting the sort of times you've said you are then you're a damn site faster than me! Not necessarily true. At 100+ you've got the effect of downforce which will help, at 40, no downforce, therefore not as much grip and easier to loose. Yes, spinning the wheels won't help really. But backing off in any conditions, no matter how slight, will result in a wieght shift away from the back wheels and so loose grip. Of course, taking it easier on the power in the first place will stop the wheels spinning and probably the slide. It's important to have a good exit speed, so you can sacrifice a little entry and corner speed to get early on the power, apply it evenly and get out of the corner fast. (My main problem is entry and corner speed - I need to learn not to loose it under too late braking). Well soften the rear a little. You need more mechanical grip. You've got no downforce, the *** isn't enough to grip (wheels spinning), so you need to soften the suspension, give the car a bit more squat and it will bite (and a little easier on the throttle - have I said that before???). And that's the way most people end up putting their car backwards through a hedge (as we say in the UK). Too fast in a corner, back off, rear end lightens, breaks away, overtakes your front end, into the bushes... classic rear wheel drive mistake You get this sort of thing with people's road cars - they stick on very stiff suspension and big fat tyres for better grip - they then complain when it rains (and the handling is exgagerated) and they slide all over the place - big fat tyres and stiff suspension make it difficult to catch when you start to loose it. ***s. Why oh why can't we have MP NASCAR in the UK???? Boo hoo :-( Much of what I've said is really from race car dynamics. I don't know exactly how the papyrus model implements car dynamic, but it seems pretty good. With it being a sim and not real life it leads certain aspects of the dynamics to be even more exagerated than in real life due to the nature of it being a sim and having assumptions and optimisations for speed. I expect that they have modelled weight shifting in quite a thorough and complex (but simplified -??) way. This may be the cause of the problem. However, if you practice in line with the dynamic's theories you should do well. Jamie ============================================================================== ============================================================================== The opinions expressed here are my own and do not in any way represent Oracle or its policies.