Edit: Just had my first race, and had a bit af an incident. http://www.youtube.com/watch?v=dF_ss55TfNE . Can someone tell me who's fault is it (i'm in the blue car). It looked like he made a mistake to me so i moved in to pass, but i had just ~10 laps of practice, so i don't know the fastest line through the corners yet.
On paper probably more your fault. However, in reality the guy in front probably wouldn't have turned in so hard. He probably would have been aware of his mistake and been checking his mirrors. It's similar to the Marquez incident at Barcelona. But this is all about how a driver behaves in sims and reality. they aren't always the same.
So had I been the driver in front and turned in like that and you were there I might go to the stewards office to complain, but in reality I'd be more pissed off with myself for not checking my inside.
So taken the plunge and gone for the one month free trial. Done a few laps in the MX-5 @ Okayama and it feels pretty good. I'm no expert on racing physics (nor do I care that much about how realistic it is, as long as it feels fairly realistic) but the tyre slip seems fairly good, and it seems that the limit is quite easy to find. Doesn't feel quite as good as LFS, but it's a damn sight nicer than rFactor. The weight transfer in the MX-5 feels pretty good (akin to the LX4 in LFS) but then I did a few laps in the Cadillac and that seems very light on its feet, which I thought was a tad strange.
But the biggest surprise for me was actually how easy it is to use. I was expecting to be lost in pages and pages of options (I'm a big one for easy setup, one of the reasons I love LFS so much) but it's really really simple. Thumbs up from me so far
I don't know why this issue is still being discussed... The culprit has been found via telemetry, it's up to iRacing to fix it...
And no, the video doesn't show 2FMSH... Everyone half knowledgeable agreed that locking the front tyres would cause them to wash out, thus decreasing the yaw angle... But for that to work the rears would have to roll... Now in your video, the BF1 didn't have enough brake force to lock the rear wheels and nKpro and rF2 lacked any perspective to see whether the rear wheels were locked too... I didn't see the rears lock up in the iRacing bit, but the pCARS part showed that the car stopped correcting itself as soon as the rears were locked and skidded along with the same amount of yaw angle...
Agreed 100% with you BBman. If 100% (or as close as possible) forward brake bias is applied effectively the front wheels lose their directional travel and will be carried to the direction of the inertia. Basically applying a front wheel handbrake. It's actually a realistic principle if 100% or thereabouts forward brake bias is applied for this to happen but as BBman said, if the rears lock as well then the same angle of yaw will be continued and that is currently the problem with iRacing. If you bothered to read what Kunos said you'd understand this theory as that is exactly what he says in his brief. Try it in reverse on and sim, reverse and tank slap the car, you can easily use the handbrake (providing it has enough braking pressure to lock the rears equally) to correct the car.
Just because Pablo López says it's fo' real doesn't mean it is. To me it looked like on LFS at least he put all the BB to the front but he said on youtube that he didn't. I don't know whether to believe that or not, but alas that's besides the point.
I haven't paid much attention to the magic save spin hax but it just occured to me that one contributing factor also is the rear diff of the cars. Especially with racing cars that have stiffer diffs (and not open diffs) the full throttle should basically lock the diff which also makes the car snap back into neutral position. (Well technically not the throttle or the revs but the input torque from the engine to the diff).
And at least for me the iracing has always had much more sensitive diffs (just like rf) that tend to stiffen much more easily with less throttle than rf or lfs. This is most noticable on mid turn where either coming off the throttle or comingback on throttle has much more snappy effect on the car while in lfs for example it is extremely linear and smooth (just my feeling though). With the old DP in iracing this was one annoying feature as the car needed to be drifted out from corners to avoid this snap understeer caused maybe by the suddenly locking rear diff..
Kind of surprised this is not mentioned as far as I can see...
It's week-old explanations why a car with ridiculous front bias rights itself.
What iRacing is doing wrong is apparently losing too much lateral traction with longitudinal slip (confirmed by Eric Hudec) and shifting weight to the rear with throttle even though the wheels aren't moving, therefore speeding up the yaw correction instead of halting it. This last has been found out via telemetry output LAST WEEK. It's somewhere between page 10-12. Any further discussion is pointless and only confusing people, hence why we get "news" about a problem that has its cause found already... iRacing knows and it will get fixed (in time)... It certainly isn't newsworthy this late in time (and twice at that!) can we please let this die before more people with the wrong ideas start screaming "wuh, but it's in every sim/realistic!!!!!1111oneone"...
I'm not trying to stir up anything if that is what you are going about. Just writing my opinion and highlighting some aspects of the perceived flaw and handling characteristic that have not been mentioned yet...
Weight shift occurs due to torque on driven wheels. Wheels spinning put limited torque relative to limited (dynamic) slip of spinning wheels. With weight shifted rear it should be easier to lock fronts for a moment. I cant imagine iRacing have it all wrong.
Although it should momentarily shift weight to front (as torque around rear axis is neutralized by torque around front axis), creating bigger braking force.
But with very light and stiff front, big front brake bias, big braking force and ability to spin rear wheels - it can be possible. I have buggy with 90% mass on rear. At some circumstances (slippy dirt) it can be very understeery under heavy braking and rear wheels spin. I had to make front as grippy as possible (tires, soft springs) to balance it.
You make no sense. Which torque do you want to transmit with locked wheels?
There can't be a weight shift, and yet in iRacing, there is... Again, everything already discussed in the original thread, with valuable contributions by no other than Stefano and Todd (I did look again: page 6,7 and 11 are the crucial ones). Even has pretty telemetry pictures!
May I say your post is exactly what I was advocating not to do? It's yet another theory to explain the realism of a fault that has already been found and will be dealt with...
Whenever and wherever you put force with arm you are creating torque. It doenst matter if it is driving force or braking force.
Mind you dynamic friction creates force also and in fact it is not much lower than that with static friction when tire friction characteristics is not much lower after threshold of maximum static friction.
Then read my post again. My post was all about adding one aspect about the front tire washout into the discussion that was not mentioned anywhere before. If you haven't noticed there have been physics discussions on this thread before so I just felt like posting that small idea that diff locking also contributes to the situation even if it isn't mainly caused by it.
Hyper: So what? If the rear tyres are rolling they have more tractive capability than the sliding fronts in any case... In any normal setup the fronts would lock a split second before the rears, and in this short time span I doubt the diff would make much of a difference. Anyway, NOBODY but the overzealous defending fanboys had any issue with that behaviour, as that IS realistic... But thanks to them reiterating and playing chinese whispers we have one sim racing news site thinking that's a/the story here.
And: Locked. wheels. Doesn't get more steady state than that. Throttle input couldn't possibly introduce any torque because the wheels ARE NOT MOVING. (Engine wouldn't to if we hadn't a mandated auto-clutch.) And yet iRacing's cars squat down. WRONG. PROVEN BY TELEMETRY. WILL BE FIXED.
I just appear to have a massive pace and driving issue with iRacing at the minute. Either I'm a crap driver or LFS has taught me to drive "wrong". Last week there was MX-5 @ Okayama Short, which despite being a shit track was ok, and I was pretty competitive. Multiclass MX-5 @ Laguna Seca was again pretty good, Street Stock at US International was ok depending on the amount of n00bs and the Cadillac I'll come back to. But this week everything has gone really wrong. The MX-5's are at Lime Rock, which is a track I love but I'm woefully uncompetitive mainly because I'm so slow on the exits of corners, people are literally driving straight past me on the main straight. I've tried doing the last corner by shifting before, during and after, flat out, braking, lifting, hard turn in, shallow turn in, gradual turn in, and still people keep overtaking me Multiclass is at Okayama Long which is alright I suppose, and the stocks are at Charlotte, which is the most confusing thing ever. I swear I take the same line through T3 and 4 every lap but I always either exit the turn doing 139mph or 135mph, nothing inbetween. If it's 135 then I'm woefully slow for the whole next straight and I just can't understand why. Add in the fact that speedways are terrifying and there's just cars all over the place means I'm pretty much just letting people past at the moment
I think my road course issues come from the fact that I'm an aggressive driver and like a good front end on a car to throw into the corners, but this really doesn't seem to work on iRacing. Everything just seems to understeer constantly.
Starting with the fixed set Mazda, there's quite alot of understeer and as far as I can tell no real way of fixing it with oversteer, which isn't too bad but I was very surprised to discover that I think it's on slicks and not road tyres!? Because to me it feels like it's definitely NOT on slicks. Definitely becomes a big issue at Lime Rock because I really really can't get the nose turned into the faster corners like the even vaugely fast people do, I just understeer horribly wide, managed to get it sideways a bit a couple of times but then I lose too much speed due to sliding
The non-fixed MX-5 is really horrible to drive, at least with the set I have. The Laguna Seca set was ok, but my Okayama one understeers until you boot the power, and then it spins instantly I'm going to assume that's the setup rather than anything else, although I do find the MX-5 has an alarmingly high tendancy to go into major tank-slappers, which I swear a small-ish car shouldn't have enough inertia to do
Then there's the Solstice which I drove about 4 laps in before deciding it was rubbish. It is FWD right? I was going through T5 at Laguna Seca, had a bit of a slide on so hit the gas, which then INCREASED the yaw angle and I span Never again. And it has stupid gears.
My biggest gripe is with the SRF and most of all the Cadillac, which seem to do the same thing with regards to throttle. Now I have a background in physics and engineering so I know a bit about forces and torques and stuff (but by no means everything, particularly about diffs so please correct me if I'm wrong), but I swear the Caddy behaves very strangely off throttle. My main encounter of this is the final at Laguna Seca. I came into the corner completely neutral (no brake or throttle) and threw the car across the apex, and without applying the brake or throttle the rear came round on me and I span. Now I'm pretty sure that any car should be stable in the yaw sense (my background is planes :P) i.e. that a pure steering input (no throttle/brake) will only result in understeer (or a nice neutral response), not oversteer, particularly for a big heavy car like the Caddy. So how can the front tyres suddenly have so much more grip than the rears? Surely the inertia is going to be mostly at the front (heavy engine, no throttle) resulting in it not wanting to turn, rather than it over-turning? I'm assuming it's something to do with the diff, given that a little bit of throttle seems to cure it somewhat, if not producing vast quantities of understeer again. The SRF also seems to do this (either spin or understeer massively), plus for all cars spins are so not naturally corrected like they are in LFS, I've just now started slamming on the brakes whenever I get even a few degrees of sideslip on in order not to spin
EDIT: And also can someone tell me what good tyre temps are? My tyres were at 150F earlier and I've no idea whether that's hot, cold or indifferent :P (MX-5 btw)