Difference between 205/60r14 and 195/65R14

[IS300E30]

I have an e30 convertible and the recommended tire size was 195/65R14 from the manual. Can you tell me what improvements are there (if any) with the current tire size that is on my car 205/60r14? Better handling, better highway speed stability? Anything?

Also, with the oem recommendation of 195/65R14 the recommendation PSI is 32 in the front and 33 in the rear. Is the tire dimension different enough that I have to change the PSI from the OEM recommendation? I like to keep everything in specs.

[redpga]

The 205/60/14 is 10mm wider, and around 10mm shorter in diameter. It will makes speedometer reading to be faster than actual speed and improve stability by an unnoticeable bit.

[IS300E30]

The 205/60/14 is 10mm wider, and around 10mm shorter in diameter. It will makes speedometer reading to be faster than actual speed and improve stability by an unnoticeable bit.

Thank you, thank you. SO, that would be the reason that my speedometer on my car says 80 while my GPS is stating I am only doing 70?

[Cicatriz ESP]

http://www.miata.net/garage/tirecalc.html

[redpga]

Thank you, thank you. SO, that would be the reason that my speedometer on my car says 80 while my GPS is stating I am only doing 70?

It's more like you're doing 78 and your speedometer says 80.

[Fugitive5]

In a perfect world the 205/60 would have a 123mm sidewall and the 195/65 would have a 117 mm sidewall with a differenct in diameter of 5mm. 205 is the section width (tread), 60 is the aspect ratio (sidewall height as a percentage of section width).

In the REAL world, A 205/60 R 14 is considered a PLUS 0 to the 195/65 R 14. In other words, close enough in diameter to not have a discernable effect on the car, including speedometer calibration. Also in the real world, manufacturers measure these numbers differently. The section width is meadured at the widest point in the tired which could be closer to the tread area, or in the middle of the sidewall, so even two tired of the same rated sizes MAY have slightly different overall diameters due to different design, manufactuer, tread depth... etc.

The typical inflated diameter for a 195/65 R 14 is 24". The few 205/60 R 14 tired that tires rack listed were about 23.7" This gives the 195 a circumference of 75.4" and the 205 a circumference of 74.5". In other words. less than a 2% difference witch is NOT going to cause your speedo to be off by over 10%.