Just brought my 2000 TJ Magna last week. I see the specs are for 205/65-15 tyres on the standard 15" alloy wheels.

My car has 215/60-15's (Falken ZE326) and I wondering what impact or reasoning for the previous owner to put on the 215/60's instead of the spec/factory 205/65 size?

the previous owner probably wanted better traction so got wider tyres..
(if you didnt know the 215/ part refers to the tyres width)

theres no problem at all with what you have now, just means you have more tread touchin the road, probably safer and better handling for you now.

:)

Use THIS (http://www.miata.net/garage/tirecalcold.html). It will tell you what the size difference is of the two tyres compared to each other, and what difference it makes to your speedo etc... :D

u might get defected for it

So long as the rim width is ok to the tyre width he's fine, the profile of the tyre has dropped to match the increase in width, so the overall diameter change shouldn't be much.

Matthius

what about the speedo error?

the previous owner probably wanted better traction so got wider tyres..
(if you didnt know the 215/ part refers to the tyres width)

theres no problem at all with what you have now, just means you have more tread touchin the road, probably safer and better handling for you now.

Yeah, that was my thinking too. Got the RWC on the car last week and the mechanic noted to my wife (who took it in for the RWC) that they tyres sizes weren't stock (but no problem re: RWC) and that we shoudl consider changing back to stock sizes when the current tyres need changing. The mechanics reasoning ... the car would feel more stable and track better on the road.

Since I share the same feeling as you when it's such a small difference in diameter, I couldn't understand the mechanics reasoning. Since I'm knew to Magna's, I thought I see what the well experienced in here had to say before deciding if my mechanic was being reasonable or not on the tyre size issue.

Use THIS (http://www.miata.net/garage/tirecalcold.html). It will tell you what the size difference is of the two tyres compared to each other, and what difference it makes to your speedo etc... :D
Thx. That's an excellent tool.

215/60's have a slightly smaller total cirumference (2007mm vs 2034mm), and thus a few more (6) revolutions per km travelled compared to the stock 205/65's

Makes the speedo apparently 1.3% too fast, so when its reading 100km/h, I'm only doing 98.7km/h. What's the std level of {in}accurracy on TJ speedometers anyways?

The 215/60 profile is meant for 16 inch rims as on the Sports model. You won't be going as fast as your speedo reads.

the difference is still within specifications though.. its not noticable and wont cause u to have any speeding fines :D

if the tyres need changing, id say go back to the stock specs.. the 205/65-15 are much cheaper to buy than 215/60

so unless you really really want better handling, stick with stock when ur gettin new tyres.

But you all forgot one very important aspect of tyres. Its load capacity. 215/60 has a load rating of 94 and unless you drive a vrx/sports you need 95. In the event of an accident
and the insurance company deems that the tyres caused the accident you won't be
covered at all. Even if the tyres weren't the cause of the accident they can say it
contributed to the accident.

But you all forgot one very important aspect of tyres. Its load capacity. 215/60 has a load rating of 94 and unless you drive a vrx/sports you need 95. In the event of an accident
and the insurance company deems that the tyres caused the accident you won't be
covered at all. Even if the tyres weren't the cause of the accident they can say it
contributed to the accident.

different brands/models have different load ratings dont they

different brands/models have different load ratings dont they

Most tyres in the size and profile are performance oriented and has less load rating.

Bridgestone does not have a tyre of that size in 95. Neither does Goodyear. Nor Dunlop.
Nor Toyo.

Yokos C.Drive claims to be 98 but i think its a missprint as its 225/60 has 96???
So goodluck finding one that'll have 95 or higher.

ahhh fair enough, well your the expert on tyres and handling mods:D

ahhh fair enough, well your the expert on tyres and handling mods:D

Do I detect a hint of sarchasm :badgrin:

I had 225/50/ZR16 on my previous KS Verada, lowered etc and she drove like she was on
rails. 225/50/16 had a load rating of 92 which was fine for 2nd gens. 215/60 would be a
better tyre but there's always the legal side of things.

But you all forgot one very important aspect of tyres. Its load capacity. 215/60 has a load rating of 94 and unless you drive a vrx/sports you need 95. In the event of an accident and the insurance company deems that the tyres caused the accident you won't be
covered at all. Even if the tyres weren't the cause of the accident they can say it
contributed to the accident.
Arrghhhh.
I have Falken ZE-326 (215/60/15) 94H .. so mine have a load rating of 94 and thus inappropriate for the car.

They were sold/fitted, for the previous owner, by a Tyre Plus (aka Michelin) dealer - they were "Ensign Tyre and Brake" at time of fitting - in late Oct/04 and have since done 15,000km. What would be my recourse against this business for replacement with correct tyre specification?

Arrghhhh.
I have Falken ZE-326 (215/60/15) 94H .. so mine have a load rating of 94 and thus inappropriate for the car.

They were sold/fitted, for the previous owner, by a Tyre Plus (aka Michelin) dealer - they were "Ensign Tyre and Brake" at time of fitting - in late Oct/04 and have since done 15,000km. What would be my recourse against this business for replacement with correct tyre specification?

Problem is that they probably mentioned it to the previous owner and the previous owner
still requested it to be fitted.

Just like any modification that makes a car unroadworthy. Exhaust places, suspension
shops, etc will fit what ever you want. All they need to do is to tell you if they are illegal
or not and have it on paper to cover their own butts. Most things will say not for street
use etc.

i havnt understood much of what was written,however, bigger tire is more grip, i had lots of grip issues with the stock 15's on my tf, got 17's and its good now,i would think he wanted more grip without buying bigger rims. if stock 15's have the required load rateing of 95, why doesnt the wider 15's have teh same or higher load rateing, they have more surface area to distribute the weight???

i havnt understood much of what was written,however, bigger tire is more grip, i had lots of grip issues with the stock 15's on my tf, got 17's and its good now,i would think he wanted more grip without buying bigger rims. if stock 15's have the required load rateing of 95, why doesnt the wider 15's have teh same or higher load rateing, they have more surface area to distribute the weight???

Because the wider tyre has a lower profile. 60 as opposed to 65. The profile determines the height of a tyre wall as a percentage of its width. Thus
60% of 215 = 129mm
65% of 205 = 133.25mm
thats a difference of 4.25mm which means the new overall diameter would be 8.5mm less than the old one.