145/80-13 tires on ebay
 

I saw these on ebay and would buy them myself for my vx but I already have a brand new set waiting to go on, it sucks cause I really want to know how a 145 tire would work. so someone buy these and find out.... oh these are the same diameter as the stock 165 tires..


https://cgi.ebay.com/ebaymotors/ws/eB...TQ:MOTORS:1123

If I didnt just get my 155 85 13s, these would be good winter tires I would assume. They probably would be stretched a bit on the "wide" VX rim, since my 155s do have to stretch outward a little to fit my rims.

forget that....slower speed
 

I would steer clear of them just for the fact that you'd be turning at a higher RPM, since the overall diameter is smaller than you stock overall diameter. Assuming you haven't been here (or someplace else like it) before, just plug your sizes in the calculator:

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

umm I did use that calculator and the 145 tire is a tad bit taller....;)

165/70-13 stock tire
sidewall= 4.5"
radius= 11.0"
diameter= 22.1"
curcumf= 69.4"
revs/mile= 913.0

145/80-13 new tire
sidewall= 4.6"
radius= 11.1"
diameter= 22.1"
curcumf= 69.5"
revs/mile= 911.0

Well, there you go, then. I was using a 175/70-13 as your stock tire size, which is why I calculated a slower speed. Grab those 145's then!

I've seen some 75 and 80 profile tires that roll like tank tracks even when filled to 40 psi (35 sidewall) so what you gain in loss of frontal area you might lose again in rolling resistance.

those tires are a good deal.