The tire debate: normal and sport

[Duck]

Many expert players say that normal N2 tires (the middle normal or standard tyres) are the closest to the common tires that come with stock cars, or in other words, the car we can drive in real life. I think this is correct, and some slow cars can be simulated in a more realistic way with N1 tires (the normal economy). IMHO there are cars, stock I mean, that comes with RD (N3) like tires; cars like Ferrari, Lotus are equipped with high performance tyres, N2 must be too poor.
In other ways, I tried to play with SM tires, but it's fair true that have too much performance. Even the 3 wheeled Daihatsu Midget changes into a monster cornering car (even better many 4 wheeled...).
In a performance comparison, N2 tires, with less rubber on the ground, seem to be faster in straights (less rolling resistence, good job PD).
An example:
Fiat 500 F
102.4kmh with SM tires, 0-100kmh in 1'16"1
102.8kmh with N2 tires, 0-100kmh in 1'13"7

The above mentioned Midget:
improved Midget Nurburgring laptime from 17'29" to 17'23"
Motegi ring from 1'40"x to 1'39"x
of course, on other tracks times are higher


What about the sport tires? There are stock or race cars that mount these V design rubbers?

Race tires are obliviously slick. No more to say.

[edit] correct tire codes (Have you ever seen a tyre?)

 

[dbartucci]

I think when people talk about N2 as the most realistic, they aren't necessary refering to realism compared to driving the actual car, but rather which tire allows them to closest replicate the track time for the actual car. An I believe it was N2 for the race cars, the fact that real ones might use slicks notwithstanding.

Edit - you took a midget around the ring and didn't fall asleep?👍

 

[hitman146]

thank you i didn´t know that finaly somebody proved that n2 tires are faster than s2

 

[Crayola]

In a performance comparison, N2 tyres, with less rubber on the ground, seem to be faster in straights (less rolling resistence, good job PD).

You know that the size of a tire doesnt effect the coefficient of friction, and therefore drag? Also the rolling coefficient of friction is incredibly low in fact its lower than sliding 2 pieces of greasy steel across each other so I doubt the normal tires would be any slower on the straights.

 

[vladimir]

You know that the size of a tire doesnt effect the coefficient of friction, and therefore drag? Also the rolling coefficient of friction is incredibly low in fact its lower than sliding 2 pieces of greasy steel across each other so I doubt the normal tires would be any slower on the straights.

but why do bicycle racers use such narrow tyres then?

 

[nitroice0069]

They use narrower tires because it cuts the wind. Bicycle racers are all about eliminating aerodynamic drag. Hence the funky suit and helmet and solid wheels etc. Also it is easier to maneuver with thin tires and actually easier to balance

JamEs

 

[Crayola]

but why do bicycle racers use such narrow tyres then?

Different drag, wind resistance. Actually rolling friction is more dependant on surface area than sliding friction so its quite possible that it has some effect, but not nearly as pronounced as those lap times suggest. Bike racing possibly, but also because its lighter. I do have a racing bike btw but I only use it on the road and its great fun. Nothing like going past cars that are stuck in traffic while keeping fit.

 

[AlecD]

but why do bicycle racers use such narrow tyres then?

Partially due to the fact that cyclist, and motor bikes contact area with the road changes as they lean to go around corners. I.e. the contact patches changes with the lean of the bike.

 

[RenesisEvo]

Partially due to the fact that cyclist, and motor bikes contact area with the road changes as they lean to go around corners. I.e. the contact patches changes with the lean of the bike.

This is also true of cars... as you corner, the contact patch changes from an ellipse to a more blob-like shape. The more rigid the tyre, the less it changes...

Surface area has little to do with friction - its the normal reaction force that counts - F = (mu) x R for anyone who knows it. Those who dont - basically, the more weight you put on a tyre, the more it grips. Hence the whole principle of weight transfer when driving.

 

[Duck]

I think when people talk about N2 as the most realistic, they aren't necessary refering to realism compared to driving the actual car, but rather which tire allows them to closest replicate the track time for the actual car. An I believe it was N2 for the race cars, the fact that real ones might use slicks notwithstanding.

Edit - you took a midget around the ring and didn't fall asleep?👍

no, the ring is funny with all cars I tried, not sure with 1886 cars
the downhills [Hatzenbach to Breidscheid] and [Hohe Acht to Schwalbenschwantz] are a must even with 15-20CV cars 👍

I slept at Le Mans, of course

 

[vladimir]

maybe the normal tyres are also harder than the sports tyres, which might eliminate some of the friction, or not?

i would not have thought that the size of the tyres plays such a huge role for aerodynamic drag...but i prefer my mountainbike with fat tyres anyway.

 

[kensei]

N1s are the tires that allow you to match real life laptimes in normal cars.

S1s are the same for race cars.

N tires are faster in a straight line, slightly...but S tires will make up that time and then some on launches and cornering.

 

[Duck]

You know that the size of a tire doesnt effect the coefficient of friction, and therefore drag? Also the rolling coefficient of friction is incredibly low in fact its lower than sliding 2 pieces of greasy steel across each other so I doubt the normal tires would be any slower on the straights.

In GT4, speeds are higher with N2 tires. This is a fact noticeable at least with low powered cars.

From Tirerack web site
A tire's rolling resistance does affect fuel economy. ........ In order to meet these demands, these tires are often designed with a priority on reducing weight and rolling resistance and are molded with slightly thinner sidewalls, shallower tread depths and use low rolling resistance constructions and tread compounds.


Don't forget we are speaking about a 0.3-0.5kmh difference.

 

[Duck]

N1s are the tires that allow you to match real life laptimes in normal cars.
S1s are the same for race cars.

is this your opinion or have some aknowledgements?

imho:
N1 for historical original tires: I tried them on a Elise....even my Opel Corsa 1.0 has more grip on clean roads (?). Even a Fiat 500 with modern brand tires corners better. I can say nothing about modern recycled tires. I think they can be N1 tires.
N2 for the most cars.
RD (Radials) for high performance cars (Which? Of course RUFs and Co., but what about cars like BMW M5, Impreza WRX, Lancer Evo, Lotus Elise?)

S (racing, not slick) tire from Pirelli

I think all this is important to define what is a "stock car" (not tuned)

 

[kensei]

is this your opinion or have some aknowledgements?

imho:
N1 for historical original tires: I tried them on a Elise....even my Opel Corsa 1.0 has more grip on clean roads (?). Even a Fiat 500 with modern brand tires corners better. I can say nothing about modern recycled tires. I think they can be N1 tires.
N2 for the most cars.
RD (Radials) for high performance cars (Which? Of course RUFs and Co., but what about cars like BMW M5, Impreza WRX, Lancer Evo, Lotus Elise?)

S (racing, not slick) tire from Pirelli

I think all this is important to define what is a "stock car" (not tuned)

Ya, I made it all up.

Nevermind this, what can 2 weeks of tire testing data matched to real world laptimes tell ya.

Sorry dude, but you are beating a dead horse into the ground.

 

[Duck]

Ya, I made it all up.

Nevermind this, what can 2 weeks of tire testing data matched to real world laptimes tell ya.

Sorry dude, but you are beating a dead horse into the ground.

I'm sorry for the horse
I never have seen that thread. Please close this topic and continue on the original one.

 

[IAG]

Kensei did u ever test any Front wheel drive cars? PD really messed up something with the traction on FWD. It was the same issue with GT3, ctr with 300hp on sport tires couldnt get a realistic time.

Well the only way i can match real life lap times of FWD cars is with ROAD tires.
Example: according to best motoring the 1998 Honda integra type R ran a lap of 1'09.01 at Tsukuba. In Gt4 I can get consistant mid 1'09s.
When Best motoring tested the same integra on the endurace race, the lowest lap was a low1'10, the driver was saving tires.

Using Economy tires (n1s) the integra is above 1'14s, i think it was higher I i dont remember exactly as i was highly dissappointed and stopped.

If i remember correctly AWD/4WD vehicles have similar issues. I couldnt get the evo/wrx spec to the B.M times with n1s. Comfort tires lapped more realistic times.

I think theres a little pattern here. Most real wheel drive cars will give you RL times with N1s. 4WD, with comfort and FF with Road. complicated, yep.

 

[IAG]

bump