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Running a C4 in the lemons/chump series. Car came with salad shooters and tires that are so dry rotted they leak air out of the sidewall. The stock size (255/50/16) is an uncommon size. What sort of range of tires can you put on these? Can you squeeze a 245/50/16 on? This car will be track only FYI, and the tires have to have a tread wear rating of 200 or higher.
I've had 245 50 16 tires for about 5 years now since I couldn't find 255's at the time. I thought they looked fine but you be the judge.
I just changed to C5 Z06 wheels this summer.
The 245’s don’t quite fit the wheel wells like the right size, but they would drop the gear ratio a little, might help at the strip if the tires have enough traction. Probably not though.
The 245’s don’t quite fit the wheel wells like the right size, but they would drop the gear ratio a little, might help at the strip if the tires have enough traction. Probably not though.
I'm confused by your comment, how would going from 255s to 245s change the gear ratio? Thats only changing the tire width, wouldn't they be the same height if they are both 50s?
I'm confused by your comment, how would going from 255s to 245s change the gear ratio? Thats only changing the tire width, wouldn't they be the same height if they are both 50s?
The "50" part of the tire size is the sidewall height expressed an aspect ratio of the section width (245 or 255) multiplied by the aspect ratio (0.50), not an absolute dimension. For both the 245 and 255, the sidewall height is half of the section width, or 122.5mm and 127.5mm respectively. This results in a total tire diameter of 25.6" and 26" respectively. In practice, the difference in speedometer calibration is small, and either diameter is completely acceptable for a C4 (later C4s came with 25.6"-diameter tires from the factory).
Last edited by MatthewMiller; Sep 20, 2021 at 10:16 AM.
Understood, but I was responding to a new reply. These topics (245s for turbine wheels and aspect ratio) come up from time to time, so I thought it was appropriate to add a little tech.
The "50" part of the tire size is the sidewall height expressed an aspect ratio of the section width (245 or 255) multiplied by the aspect ratio (0.50), not an absolute dimension. For both the 245 and 255, the sidewall height is half of the section width, or 122.5mm and 127.5mm respectively. This results in a total tire diameter of 25.6" and 26" respectively. In practice, the difference in speedometer calibration is small, and either diameter is completely acceptable for a C4 (later C4s came with 25.6"-diameter tires from the factory).
Need a tire size recommendation;
