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Tire pressure question
- Thread starter Brosky
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Geo Hahn
Yoda
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[ QUOTE ]
I thought tire pressures was based on the make and model of car that you have, not the tire.
[/ QUOTE ]
The TR3A manual specified different pressure for the various tyres available... also different pressures based on type of driving planned. Sounds like they later simplified it to one set of numbers (like most modern car manufacturers do today).
I thought tire pressures was based on the make and model of car that you have, not the tire.
[/ QUOTE ]
The TR3A manual specified different pressure for the various tyres available... also different pressures based on type of driving planned. Sounds like they later simplified it to one set of numbers (like most modern car manufacturers do today).
OP
Brosky
Great Pumpkin
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Some more info from reliable sources:
https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=73
https://www.sportcompactcarweb.com/tech/0208scc_tire_pressure_guide/
From the above article:
"In the event that you aren't able to find a recommendation for your car, or the tires on your car are so different from those that were originally fitted from the manufacturer as to be incomparable, we received the following rule of thumb from Oscar Pereda, an engineer for BFGoodrich. He calls it a "realistic starting point," saying it has never been just right, but is a good place to start. The rule is:
(Vehicle Weight in lb/100) + 2 psi at heavier end + 2 psi all around if suspension and alignment are stock.
Example: Stock 911, 3,000 lb.
(3000/100) = 30 psi
Add 2 psi all around = 32 psi
Add 2 psi to heavy end = 34 psi at rear
With modified suspension, the result is 30 psi front, 32 psi rear."
Using that forumla and the two following weights the pressures could range from
Curb weight = 2624 / 100 = 26 lbs +
Gross weight = 3042 / 100 = 30 lbs. +
https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=73
https://www.sportcompactcarweb.com/tech/0208scc_tire_pressure_guide/
From the above article:
"In the event that you aren't able to find a recommendation for your car, or the tires on your car are so different from those that were originally fitted from the manufacturer as to be incomparable, we received the following rule of thumb from Oscar Pereda, an engineer for BFGoodrich. He calls it a "realistic starting point," saying it has never been just right, but is a good place to start. The rule is:
(Vehicle Weight in lb/100) + 2 psi at heavier end + 2 psi all around if suspension and alignment are stock.
Example: Stock 911, 3,000 lb.
(3000/100) = 30 psi
Add 2 psi all around = 32 psi
Add 2 psi to heavy end = 34 psi at rear
With modified suspension, the result is 30 psi front, 32 psi rear."
Using that forumla and the two following weights the pressures could range from
Curb weight = 2624 / 100 = 26 lbs +
Gross weight = 3042 / 100 = 30 lbs. +
I was also under the impression that if one goes with a wider tire than stock (per the pressure chart of the vehicle), there is more surface area and the pressure will actually be slightly less.
Of course I have a friend who likes his truck tires at 45lbs - even though the vehicle decal indicates proper tire pressure should be 35lbs. "better handling"..........
Of course I have a friend who likes his truck tires at 45lbs - even though the vehicle decal indicates proper tire pressure should be 35lbs. "better handling"..........