Author Topic: Tyre sizes  (Read 3329 times)

0 Members and 1 Guest are viewing this topic.

Offline listo

  • Soft Floor Camper User
  • ****
  • Posts: 530
  • Thanked: 47 times
  • Gender: Male
Tyre sizes
« on: March 01, 2017, 09:14:05 PM »
Sorry to bore you guys with this question but I'm not the most technical penut in the turd. If my car has 245 tyres on it from the factory, will 265 make much difference?
Thanks

Offline ATC

  • Soft Floor Camper User
  • ****
  • Posts: 323
  • Thanked: 15 times
  • Gender: Male
Re: Tyre sizes
« Reply #1 on: March 01, 2017, 09:39:26 PM »
Sorry to bore you guys with this question but I'm not the most technical penut in the turd. If my car has 245 tyres on it from the factory, will 265 make much difference?
Thanks
Listo,
The 245 is just the width, we'd need to know all three numbers to give a good answer.

Google 1010 tyres, they have a tyre size calculator on their website, put in the factory size, then the new tyre size you are looking at, it will tell you how much of an increase in diameter and circumference the change is.

On my Auto BT50 i went up a tyre size from 265/65/17 to 265/70/17 and you can feel the loss of power.
Note this is in an auto.

If you have a manual it migh not be as bad, but an increase in tyre size gives you an in increase looks, but a loss of effective power.

If the tyre change is big enough then change diff ratios to fix the gearing.



Sent from my SM-T815Y using Tapatalk


Offline tryagain

  • Hard Top Camper User
  • ******
  • Posts: 3520
  • Thanked: 609 times
  • Gender: Male
Re: Tyre sizes
« Reply #2 on: March 01, 2017, 09:43:28 PM »
It depends what you mean by difference, just going by the 245-265 change will give you 20mm extra width if we were talking about say 245/70's vs 265/70's it would also give you 28mm additional overall height. The second number is the percentage of the width that equals the wall height.

Offline listo

  • Soft Floor Camper User
  • ****
  • Posts: 530
  • Thanked: 47 times
  • Gender: Male
Re: Tyre sizes
« Reply #3 on: March 02, 2017, 07:03:09 AM »
Thanks guys, the tyres on now are 245/70/17, there seems to be more variety in brands with 265/70/17. 1010 doesn't recommend the size change & given I've already changed the profile from 65 to 70 I probably shouldn't do this.

Offline Aaron Schubert

  • Hard Floor Camper User
  • *****
  • Posts: 843
  • Thanked: 78 times
    • 4WDing Australia
Re: Tyre sizes
« Reply #4 on: March 02, 2017, 07:16:09 AM »
On the drivers side pillar of your vehicle (near the seat) it should tell you what the factory tyre sizes should be.

Going up like you've suggested is 3.6% bigger. You'll lose some power, torque and fuel economy, and make the vehicle work a bit harder but it will be pretty minimal. On the flip side you get more clearance and a better variety of tyres. Just make sure its legal, and that they aren't going to rub

Aaron
My Isuzu Dmax

Check out my blog at 4WDing Australia

Offline Steffo1

  • Hard Top Camper User
  • ******
  • Posts: 2208
  • Thanked: 247 times
  • Gender: Male
  • More I learn about women, more I like my ute
Re: Tyre sizes
« Reply #5 on: March 02, 2017, 09:16:28 AM »
Also, if altering (+/-) diameter, your speedometer, if mechanical, will most likely  be reading more inaccurately.
'93 4.2 TD 'Cruiser 'tilly
'08 TD V6 Disco 3
'10 16' Evernew Pop Top

"sit bonum tempora volvunt"

Offline Bird

  • Once Was Lost, now am found
  • Hard Top Camper User
  • ******
  • Posts: I am a geek!!
  • Thanked: 1874 times
  • Gender: Male
  • Life is far too long....
    • My Place.
Re: Tyre sizes
« Reply #6 on: March 02, 2017, 09:21:56 AM »
I think the marked size on tyres is only an estimate or suggestion... Some manufacturers tyres in the size for example "285/75x16" are more than an inch smaller and quite a bit narrower than other of the same size..
Its not how its meant to be, but thats just how it is.
-
Click to enlarge

Gone to a new home

Offline cheif carlos

  • Soft Floor Camper User
  • ****
  • Posts: 301
  • Thanked: 9 times
Re: Tyre sizes
« Reply #7 on: March 03, 2017, 11:06:21 PM »
I say just do it. over 21+ years of owning 4wd's I have had everything from 35's on an '84 4 Runner (2lt petrol) to now more conservative 285/75/16 on the Landcruiser.
any tyre mods from standard come with a loss of power but if you want them just go for it.
Need to get the backside into gear and get out camping

Offline marvellous_matt

  • Soft Floor Camper User
  • ****
  • Posts: 484
  • Thanked: 49 times
  • Gender: Male
Re: Tyre sizes
« Reply #8 on: March 04, 2017, 10:13:17 AM »
Im pretty sure when getting insurance I was allowed to go up one size, but not 2. Might be worth looking into, would be terrible if a something happened and you were not covered. Not sure how on the ball insurance assessors are in these matters,  could be an urban myth that you would get caught. I hated the missus driving our old 4WD when it had bigger wheels on, spedo did not allow for any error and I was sure she would get fined.

Offline listo

  • Soft Floor Camper User
  • ****
  • Posts: 530
  • Thanked: 47 times
  • Gender: Male
Re: Tyre sizes
« Reply #9 on: March 04, 2017, 03:31:40 PM »
I'm just going to stick with the size that I've got. The prospect of losing power & economy isn't  very entertaining, given there's little of either to lose as it is.
« Last Edit: March 07, 2017, 07:28:05 PM by listo »

Offline #jonesy

  • Hard Floor Camper User
  • *****
  • Posts: 1326
  • Thanked: 163 times
  • Gender: Male
Re: Tyre sizes
« Reply #10 on: March 07, 2017, 06:27:49 PM »
It will give you about 28mm in overall height, but only raise the car 14. The other 14 is above the axle. As stated Not all tyres the same listed size are actually the "same" size. I put AT on mine that ware the same as the original tyres but they rub on full lock left when I reverse out of my driveway. I have a steep drive so the car is raised as I turn out.
2013 Aussie Jays - Crusher      2013 Toyota Hilux.