Physics Tyres once again...

Hello there i decided to refine my tyres model once again ..
to create Z-tune i had to replace tyre set from 245/25R18 to 265/25R18 i didn't found anything which would be considered as street tyre that's why i've chosen to go higher and took 265/25R19 instead from Pagani Huayra front tyres ( mostly cause of tyre version [v10])

at first i was happy with the result - car gained traction but tyre temps were off the limits after few corners - that's why i changed FRICTION_K but now I need to change the grip of the tyre and I do not know which parameter is important ....

DAMP=600
RATE=323960
DY0=1.6426
DY1=-0.044
DX0=1.5866
DX1=-0.044
WEAR_CURVE=__cm_tyre_wearcurve_rear_4.lut
SPEED_SENSITIVITY=0.003161
RELAXATION_LENGTH=0.07471
ROLLING_RESISTANCE_0=12
ROLLING_RESISTANCE_1=0.00050
ROLLING_RESISTANCE_SLIP=5245
FLEX=0.000448
CAMBER_GAIN=0.097
DCAMBER_0=1.5
DCAMBER_1=-13
FRICTION_LIMIT_ANGLE=7.51
XMU=0.22
PRESSURE_STATIC=23
PRESSURE_SPRING_GAIN=1980
PRESSURE_FLEX_GAIN=0.4
PRESSURE_RR_GAIN=0.55
PRESSURE_D_GAIN=0.0005
PRESSURE_IDEAL=32
FZ0=3468
LS_EXPY=0.7461
LS_EXPX=0.8089
DX_REF=1.51
DY_REF=1.48
FLEX_GAIN=0.041
FALLOFF_LEVEL=0.88
FALLOFF_SPEED=2
CX_MULT=1.08
RADIUS_ANGULAR_K=0.02
BRAKE_DX_MOD=0

[THERMAL_FRONT_4]
SURFACE_TRANSFER=0.0180
PATCH_TRANSFER=0.00027
CORE_TRANSFER=0.0012606
INTERNAL_CORE_TRANSFER=0.0034
FRICTION_K=0.02581
ROLLING_K=0.19
PERFORMANCE_CURVE=__cm_tyre_perfcurve_front_4.lut
GRAIN_GAMMA=1
GRAIN_GAIN=0.5
BLISTER_GAMMA=1
BLISTER_GAIN=0.5
COOL_FACTOR=1.85
SURFACE_ROLLING_K=0.96492
 
RATE=323960

The spring rate or " RATE" of the tyre will affect the grip greatly as it allows the tyre to keep in contact with the road better on corners, lower it to increase grip by trial and error by percentage, try 10%, 15% & 20% less for starters. Don't know what it does to the wear of the tyres though, may be nothing or may be a lot, try it and see.
 
The spring rate or " RATE" of the tyre will affect the grip greatly as it allows the tyre to keep in contact with the road better on corners, lower it to increase grip by trial and error by percentage, try 10%, 15% & 20% less for starters. Don't know what it does to the wear of the tyres though, may be nothing or may be a lot, try it and see.
That's not how AC works...changing the spring rate won't directly change grip in AC (there's no real contact patch simulation).

@Grabarz you need to adjust DY_REF and DX_REF (lateral and longitudinal grip coefficients at reference load) to directly adjust grip. The V5 Tires thread on the official forum (in the physics modding section - sorry no link...on mobile) has the equations to calculate grip at a given load.
 
That's not how AC works...changing the spring rate won't directly change grip in AC (there's no real contact patch simulation).

Well for whatever reason lowering the "RATE" value greatly increases the grip of the tyres, to prove this I have a set of soft tyres with 3 different "RATE" values, I cut and pasted the soft tyre 3 times and simply changed the names, in the tyre.ini file, the stock value and 10% & 20% less, so soft normal, soft 10% and soft 20% with everything else the same, so in game I can swap between them knowing only the "RATE" value is different, even the wear and tcurves both point to the same files.

Now I can lap faster, depending on which tyre I choose, normal is slowest, then 10% and 20% is fastest. The lap times don't lie IMO. So if you want better grip from custom tyres start by lowering the "RATE" value.
 
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So if you want better grip from custom tyres start by lowering the "RATE" value.

thanks for advice but since i promised myself to be honest with reality i cannot do that. Reason is simple those tyres are 265/25R19 they cannot be "soft" enough they should be hard as rock, uncomfortable but grippy
that's why i increased DY_REF and DX_REF both by 0.03 and it's fine for me now

however I'm struggling with suspension now - and i have no clue how to make it stiffer ( less bodyroll ) ...
 
[QUOTE="Grabarz, post: 2504504, member: 253933"
however I'm struggling with suspension now - and i have no clue how to make it stiffer ( less bodyroll ) ...[/QUOTE]

suspension.ini = adjust BASEY, this changes your relation to CG raising or lowering the body roll
car.ini = adjust GRAPHICS_OFFSET, adjust the y axis to get the body back in position

After you have the desired body roll (don't go too far) then set your ARB's.
 

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