One of the best posts read. So much beauty in your words.
Everage (average) computing power my friend is huge today.
Clean code that takes advantage of this power is no where in this world.
Multi threading is the future and after the creation of quality compilers, programming hardness every day is passed to the logic of splitting things apart in software development.
Somewhere here is the loop hole Mr. Scawen has entered.
He needs (fun,way of thinking) to create a perfect code in an industry optimised for mass production. This is a lonely road and thank you Sir for choosing this road vs the easier ones.
I wish him lfs s4 being created by his kids :-) for our kids, in a better world.
Interesting thread. It also goes to show that tire physics are extremely complicated.
I know Tristan has way more real-world racing experience than most and I am sure he's correct, but it's pretty obvious the reason why the best lap comes after a few laps is tire pressure and temperature. For a real race, a crew chief will set the tire pressure to be less than optimum to allow for expansion when heated. That means that there is an optimum temperature/pressure where the tires will work best and it will take a couple of laps to hit that. Past that point, usually enough tread has worn off, and with the heat build-up, you'll usually never hit that optimum point again with that set of tires. (dependent on setup and other factors)
For real-world qualifying, the tire pressure is often set higher than for the race so the tires come to optimum temperature and pressure right away and they hit that sweet spot for a lap, maybe two, before the tires are done. They'll often reuse those tires for the race as "scrubbed" tires and they'll work just fine as long as the pressure is set properly for a long stint.
All of this is dependent on the setup of the car and the conditions, obviously. In endurance racing, you often hear drivers say that the tires were great all the way through the stint. This means the tires are good quality and the setup on the car was correct for the driving style and conditions. But so many other factors do come into play. I would suspect that the tire diameter has little overall affect on the results.
In LFS, I've only a few times noticed that I'm driving better laps near the end of a stint than the beginning. I suspect it has more to do with car setup and weight (less fuel) than it does the tires "gaining" grip. But that's my opinion.
I drove a couple of endurance races and I have always made PB at the end of stint if you do not count the HL laps. Why? Well, because at the beginning of a stint tires easily warm up. At the end of stint tyres are quickly cooled and it is possible to enter much faster in turn and you do not have to worry whether you overheat the tires and if you have to drive slower next five turns.
You can work this out. Acceleration can be calculated by a=f/m, where m is this case is translational inertia, rather than simply mass, and force is engine torque over wheel radius.
I took my X-Type as an example, comparing new tyres to those with a full 8mm of wear, the car ends up approximately 2% faster in 2nd gear (higher gears give a larger benefit as the engine inertia tumbels).
It looks like it's always going to be that the vehicle accelerates faster as the tyre wears (at least for typical values). I've attached a spreadsheet you can experiment with. The wheel inertia calculation is very simplified but it will do for now. I could make it generate the wheel masses and inertias for worn and unworn but it's too late and I'm very sleepy right now.
Umm.... no. The only effect on top speed will come from the changed engine velocity and thus power output.
Hey that is Cool work dude! Yeah glad ti know my theory was experimentally tested too. So acceleration increases. Interesting. But as u said since top speed does not increase, aa scawen mentioned, the error in speedo due to lessended wheel diameter persists i guess.
Interesting study Bob, hope Scawen will learn (if he already didn't) from this how tyre wear also affect to acceleration quite a lot
BTW Tonight I dreamed how Scawen implemented that skin colour also affect speed, acceleration... example end of your car is black, and front white, we know that black colour absorb heat, while white colour reflect light (heat). So it's warmer at the end of your car, that means higher pressure that is actually pushing you forward... But thats just dream
While it's really nice calculation, it's missing quite a lot.
It shows effect of less mass a wheel has, but pure inertia is only one portion of energy needed to spend to accelerate car.
Add rolling resistance of tyre, and ofc - resistance of going thru air, etc, etc...
So in the end, difference is miniscule.
While it's interesting in scientific approach, in simulator case (such as LFS), it can easily be ignored.
Intentionally. For the purposes of this comparison, rolling resistance and air drag are identical, thus while the acceleration figures given are too high, it will reduce them both by the (almost) same amount, so it's still acceptable to compare the differences between them, which is what we're interested in here.
If you add in an arbitrary resistance force (comparable to travelling faster), you'll see that in fact, the absolute acceleration benefit increases (albeit marginally), and the relative benefit can increase significantly.
One of the most interesting threads ever, in this forum.
The tyre model is alpha og omega for a simracing simulator and I just can`t wait for a realistic model.
The coding issue :
I still remember what they did with the Commodore 64 and what great programmes that were created on this "breadbox". If Scavier can come close to that quality of programming, I can wait a bit longer