tire question

[ellebycul]

I admit it I know nothing about tires...the tires on my stock steel roadster wheels say 165sr14 will P175/70R14 work?

thanks, enjoy your weekend

[datsunrides]

They will, but will be a litle wider and a bit lower in the profile. A 156SR14 would be closer to a 165/80R-14. If you want the taller profile, find a 175/75R-14, which would give you close to the same diameter.

Mark

[Fairlady66]

I use the P175/70R14 on my Roadster. I like how they ride. I had the P180 on for 1 day, and they rubbed. These I like and they are White-walls.

[mattywood]

What size tire would you use to retain the same original diameter using a 15" rim

[Nissanman]

Here is an oldie but a goody
Just ignore the tyre types on the top line, they are ancient history.
Follow a tyre size across horizontally to see an equivalent replacement for increasing diameters.

tyre data A.jpg

The number in bold type after the tyre size is the Overall Diameter of the replacement tyre.

[mattywood]

what size was the original 2000 wheel and tyre?

[Nissanman]

5.60" x 14" [or 145 x 14]
You need to know the OD of this tyre to use the chart

[mattywood]

No one seams to know the original diameter.

[mattywood]

I found this maybe its correct: http://autox.team.net/pipermail/datsun- ... August.txt

[Nissanman]

Here are 2 neat tyre calculation sites: -

http://www.bikerlifestyle.co.uk/tech/pcd/tyresize.htm

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

and a wheel offset calculator: -

http://marksink.com/tire_wheel_offset/offset.html

[fj20spl311]

I found this on a MGB site

5.60x14 diameter 24.08 FYI they also stated it had a ratio of 90

[spl310]

Unless I am mistaken, he old method of calculating wheel diameter was doubling the first number and adding it to the second - 5.60+5.60+14=25.2 - that does not take into account the bulge though...

[fj20spl311]

Unless I am mistaken, he old method of calculating wheel diameter was doubling the first number and adding it to the second - 5.60+5.60+14=25.2 - that does not take into account the bulge though...

That was true for tires made before 1949.
From Tire Rack and lots of others:
"Two versions of numeric tire sizes were used as original equipment on vehicles between 1949 and 1970. The early numeric tires had the equivalent of a 90-series aspect ratio, while later tires offered a "lower" profile equivalent to a 80-series."

5.60*.90=5.04

5.04+5.04+14=24.08

185/70x14 or 195/60x15

[spl310]

Interesting. Thanks for the news Phil!

[mattywood]

Going by what you say I should run 60 15s on a 195. I have checked price of 60s and 55s and they are $$$ for a good tyre. I had a look at alvins ride running 195 50 15s and they look fantastic and the tyre I want to run is a Yokohama C drive which much cheaper as a 50 series. Do you see an issue with handling running a 50 vs a 60? I know guys run 50s on 16" wheels in australia. I might win a prize for most indecisive 311s member.