As many of us are using 255/50/19 tyres on 19 inch wheels to improve ride and cushion but why to keep the same pressure of 42 psi recommended by Tesla If tyre load rating is higher than original tyres?
I installed Michelin pilot sport 4 suv summer tyres on 19” Gemini wheels on my model Y performance 2022.
The new tyre rating is 107Y.
The original tyres on model Y performance are 255/35/21 98W and 275/35/21 103W
These tyres Load rating as per load chart corresponds to front-750 kg at 50 psi and rear 875 kg at 50 psi.
Now considering Tesla recommended pressure of 42.0 psi we can calculate the design load.
At 42.0 psi recommended pressure safe load on front axle is 1260 kg.max approx.
At 42.0 psi recommended pressure safe load on rear axle is 1470 kg max. approx.
Model Y performance maximum Laden mass is 2415 kg.Front axle max laden mass -1125 kg and rear is 1290 kg.
Even considering the max.max allowable loading limit for axle as per chart is F-1300 kg and Rear -1500 kg.So all this falls in 42.0 psi limit for original tyres.
If we consider the same design load of front - 1260 kg and rear 1470 kg then the psi required for 107 Y load rating can be calculated.
The load rating for 107y tyre is 975 kg at 50 psi.
So minimum safe front pressure for 1260 kg is 32.3 psi and rear pressure for 1470 kg is 37.7 psi.This pressure is sufficient to support the maximum limit of vehicle loading.
I kept 35.0 psi all round and the load they can support is 682.5 kg each.Total load support at this pressure is 2730 kg which is in limits.
At 35.0 psi the car drive is as good as a land cruiser or Nissan patrol.Anything above 35.0 max the ride is uncomfortable.The suspension are not suitable for comfortable suv ride at higher tyre pressures.
I am attaching some photos.Gents what is your suggestion on this.Am I wrong in any calculation?
I installed Michelin pilot sport 4 suv summer tyres on 19” Gemini wheels on my model Y performance 2022.
The new tyre rating is 107Y.
The original tyres on model Y performance are 255/35/21 98W and 275/35/21 103W
These tyres Load rating as per load chart corresponds to front-750 kg at 50 psi and rear 875 kg at 50 psi.
Now considering Tesla recommended pressure of 42.0 psi we can calculate the design load.
At 42.0 psi recommended pressure safe load on front axle is 1260 kg.max approx.
At 42.0 psi recommended pressure safe load on rear axle is 1470 kg max. approx.
Model Y performance maximum Laden mass is 2415 kg.Front axle max laden mass -1125 kg and rear is 1290 kg.
Even considering the max.max allowable loading limit for axle as per chart is F-1300 kg and Rear -1500 kg.So all this falls in 42.0 psi limit for original tyres.
If we consider the same design load of front - 1260 kg and rear 1470 kg then the psi required for 107 Y load rating can be calculated.
The load rating for 107y tyre is 975 kg at 50 psi.
So minimum safe front pressure for 1260 kg is 32.3 psi and rear pressure for 1470 kg is 37.7 psi.This pressure is sufficient to support the maximum limit of vehicle loading.
I kept 35.0 psi all round and the load they can support is 682.5 kg each.Total load support at this pressure is 2730 kg which is in limits.
At 35.0 psi the car drive is as good as a land cruiser or Nissan patrol.Anything above 35.0 max the ride is uncomfortable.The suspension are not suitable for comfortable suv ride at higher tyre pressures.
I am attaching some photos.Gents what is your suggestion on this.Am I wrong in any calculation?