A general tire size question

[stephen wilson]

With that size, I assume it's not for a Boxster? They will be 1" smaller in diameter, which is a fairly large change, especially if the car has stability control. It may be within the safe range for ABS function though? I thought up to 5% Dia. change was OK for ABS, and you would be at around 3.2% change in diameter? Don't take that as Gospel though!

The 55 is the aspect ratio is explained in spinnaker's link. ( the tires section height is 55% of the section width of 225mm )

I installed a slightly wider, and taller tire on the front of my '06 ( 235 to 245 ), and it is right on the edge for my PSM. If I increase the front tire pressure a few Psi, the "traction control" starts kicking in.

[imsjack]

Originally Posted by stephen wilson

With that size, I assume it's not for a Boxster? They will be 1" smaller in diameter, which is a fairly large change, especially if the car has stability control. It may be within the safe range for ABS function though? I thought up to 5% Dia. change was OK for ABS, and you would be at around 3.2% change in diameter? Don't take that as Gospel though!

The 55 is the aspect ratio explained in spinnaker's link. ( the tires section height is 55% of the section width of 225mm )

I installed a slightly wider, and taller tire on the front of my '06 ( 235 to 245 ), and it is right on the sdge for my PSM. If I increase the front tire pressure a few Psi, the "traction control" starts kicking in.

thanks, stephen. that was one of my biggest concerns the stability control. I've driven a car with the wrong tire sizes (wrong diameter) and the abs was setting itself off at random (very unsafe). Seems like such a small number, but I'd hate to mess with being safe.