Tire physics

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Velocity-Wolf
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Acidhex
Tire physics.

I did not write this article and found it while merely browsing teh interwebs at work. Tony Foale appears to have significantly contributed to the applied physics of motorcycle racing, especially in regards to aerodynamics. There are quite a few good articles on his website.


Having said that, there are a few things I want to point out:

Yes, the article mainly applies to motorcycle tires.
Yes, the game does not stay true to real world physics at times. However, I feel the folks at PD have, in general, tried to imitate real life as best as they could with math; Especially with the game boasting to be "The Real Driving Simulator."
When I refer to drifting, I am not referring to aesthetics drifting. I mean going into a drift with the use of trail-braking, some love taps on the e-brake, or pure inertia.

Anyway, my hope here is to help people understand that, while that fine line between being in control and out of control can be blurry, in order to go fast you absolutely need some tire-slip.

I think this carries over into the whole slew of people complaining about the 'e-brake trick' (trail-braking with an e-brake). It also explains why drifting can be faster through an extremely tight corner versus flat-out through a subtle chicane. You don't need to drift through the chicane, because frankly, you probably don't have enough horsepower to break 100% grip. If you could, ballsing it through a chicane with 115% tire-slip, some momentum, and control over the re-action of the suspension, would probably be faster (think of T7 and T8 in Rome City Circuity (Reverse)).

Just read it. It will make you a better person.
 
Most sims allow some pretty extreme slip angles and the ability of the user to successfully walk that fine line between slip angle and sliding is what separates the fast from the fastest. There's constantly a thread on the iRacing forums about how cars can't be driven "that way". I have no real world experience, so my authority on the subject is nil, but I'm thinking to some degree it would be possible to drive a car that balls out, the problem is I doubt there's a tire out there that could handle it for any extended period of time. Plus you're risking destroying the car every lap. I also haven't put a lap in on GT5 yet, but if it's anything like most other sim to sim(ish) games all out drifting IS slower, the problem is many people that are off pace confuse manipulating the slip angle with drifting. If you flat out exceed the tires level of grip and go into a drift I've never seen that be faster, but getting the car a bit sideways milking every ounce of grip out of the tires is a totally different thing.
 
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Scooty, log in and watch some of the top10 replays and I think you will better understand my meaning of drift. Something also tells me that you didn't read the article fully that I had linked. My intent here is not to be a dick to you; please don't take it as such.
 
Oh I don't even have a PS3 yet, I was just speaking from a vague point of view I guess. Actually haven't read the article yet, guilty as charged.
 
Just read it. It will make you a better person.

Well put. Awesome article man, definitely a good read!

My favorite quote from the article:

"It has been demonstrated countless times in speedway that mid-corner engine failure or inexperienced shutting of the throttle, results in immediate intimate inspection of the perimeter fencing."

hahaha, fantastic
 
need to read the article, but I want to say that you should definitely not slide when going through T7 and T8. you lose a lot of time. keep it nice and tidy. keep your entry neat, and keep the car composed and get on the gas at apex and run it right to the barrier at exit.
 
hand brake "trick" is not a trick at all, its a technique that applies to real-world cars aswell...oversteer counteracts understeer.
 
hand brake "trick" is not a trick at all, its a technique that applies to real-world cars aswell...oversteer counteracts understeer.

Thank you for reiterating the purpose behind my single tick quoting of 'e-brake trick.' :)
 
This is a good article, the only thing to keep in mind is that the GT5 tire model is not entirely realistic in many ways. I'm guessing this is the main reason why the suspension tuning still doesn't seem to work properly in GT. Tire modeling is not simple for sure. Accurately modeling the non-linearity of the tires coefficient of friction vs weight and vs. slip angle is fairly complex. And the coefficient of friction non-linearity vs. weight is the whole reason real world suspension tuning works the way it does.
 
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