Tire Size Box

165/70R14 vs 165/80R14

165/80R14 compared with 165/70R14

+5.6% diameter, 0.0" width

165/80R14 is 24.39" tall vs 23.09". More than the 3% rule of thumb, so check carefully before switching.

23.1"14" rim4.5"6.5" wide
165/70R14 (solid) compared with 165/80R14 (dashed outline), drawn to scale

With 165/80R14 tires, when your speedometer says 60 mph you are really going

63.4 mph

165/80R14 is +1.30 inches (+5.6%) in overall diameter. That is more than the 3% most shops and makers recommend.

165/70R14165/80R14Difference%
Overall diameter23.09"24.39"+1.30"+5.6%
Section width6.50"6.50"0.00"0.0%
Sidewall height4.55"5.20"+0.65"+14.3%
Circumference72.55"76.64"+4.08"+5.6%
Revolutions per mile873.3826.8−46.5−5.3%

Speedometer difference

If your vehicle came with 165/70R14 and you fit 165/80R14, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph21.1 mph+1.1 mph
30 mph31.7 mph+1.7 mph
40 mph42.3 mph+2.3 mph
50 mph52.8 mph+2.8 mph
60 mph63.4 mph+3.4 mph
65 mph68.7 mph+3.7 mph
70 mph73.9 mph+3.9 mph
75 mph79.2 mph+4.2 mph
80 mph84.5 mph+4.5 mph

Each size on its own

Questions

Which is bigger, 165/70R14 or 165/80R14?
165/80R14 is taller by 1.30 inches (24.39" vs 23.09"). 165/70R14 is the same width.
Can I replace 165/70R14 with 165/80R14?
It is not recommended without checking carefully. The diameter difference is +5.6%, more than the 3% most shops and makers allow. It will throw off the speedometer and may affect ABS, stability control and clearance.
How much will 165/80R14 change my speedometer?
When your speedometer reads 60 mph with 165/80R14 fitted (calibrated for 165/70R14), your real speed is 63.4 mph. Your odometer will under-count miles by about 5.6%.
Will 165/80R14 lift my vehicle?
Ride height changes by half the diameter difference: +0.65 inches of ground clearance at the axle.

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