What tyres to fit for my rims?

[Mkl22]

3 hours ago, Naimed said:

Also to take note that once you run a staggered setup, you cannot rotate the tyres front to back (v. versa). You can dismount the tyres and swap left to right in most cases if you are running bigger camber settings. They say a staggered setup is more stable at the corners but in Singapore, a bit over-rated with family sedan. I run a staggered setup (factory spec) and constantly thinking of going non-staggered so I can save some money on the 245/40 tyres vs 225/45.

I was on staggered 245 rears. Still break traction especially when wet. Dry tarmac quite ok. In the end just floor it less. 

[Mkl22]

31 minutes ago, q1n3fer said:

i think the tyre shop purpose is to get the least differential as possible between front and rear with regards to overall diameter and tyre sidewall height.
am considering 235/40 and 265/35 now.

Besides trying to equalize front and rear, also try not to get odd sizes. A real pain in the butt should you need to replace in a hurry. 

[inlinesix]

3 minutes ago, Mkl22 said:

I was on staggered 245 rears. Still break traction especially when wet. Dry tarmac quite ok. In the end just floor it less. 

Wider tyre has a higher chance of aquaplaning.

[Mkl22]

3 minutes ago, q1n3fer said:

i have intentions to go for aftermarket coilovers after rims are done, so gap won't be an issue.
and u just addressed out my concern. whether 265 will protrude out of fender not
and i have to pick parents at times.. full load how also a question mark.. lol!

I’ll stick with 245 rear and 235 or 225 fronts. Is250 won’t  have the torque to break traction that much. Save some fuel with a skinnier tire. Use the wheel offset to make it more flush. 

[q1n3fer]

1 minute ago, Mkl22 said:

Besides trying to equalize front and rear, also try not to get odd sizes. A real pain in the butt should you need to replace in a hurry. 

now bobian lor. coz wanted swee and flush, go order rims with custom offset.
have to see thru it now.
am in favour of 225/40 and 255/35 now
as long as it doesn't overstretch for front. if not i'll have to go 235/40 and 265/35

[Mkl22]

3 minutes ago, inlinesix said:

Wider tyre has a higher chance of aquaplaning.

Road was damp without standing water. So nothing to do with aqua planning. 

[inlinesix]

Another point to consider:

1. Will brake rotor look puny after upgrade to 18"?

[inlinesix]

Just now, Mkl22 said:

Road was damp without standing water. So nothing to do with aqua planning. 

Too much torque then.

[q1n3fer]

3 minutes ago, inlinesix said:

Another point to consider:

1. Will brake rotor look puny after upgrade to 18"?

it definitely will. haha! especially my rims are 5 spokes.
so bbk and upgrading of stock rotor will be next in line.
never ending!

[Mkl22]

8 minutes ago, q1n3fer said:

now bobian lor. coz wanted swee and flush, go order rims with custom offset.
have to see thru it now.
am in favour of 225/40 and 255/35 now
as long as it doesn't overstretch for front. if not i'll have to go 235/40 and 265/35

Oh the rims have been bought. Ok. 
well 225/40/18 very common, 235/40/18 less so. Conversely 255/35/18 less common than 265/35/18. This is what I have gathered in the past. Not sure about now. 

Edited December 29, 2020 by Mkl22

[Mkl22]

On 12/28/2020 at 11:31 AM, q1n3fer said:

Hi all. Need some opinion here. Rims are 18 x 8.5 for front and 18 x 9.5 for rear. Which would you choose?

Option 1
225/40/18
255/35/18

Option 2
235/40/18
255/35/18

Option 3
245/35/18
255/35/18

Came across this YouTube video again. I think this should help answer some questions on staggered and sizes

 

[Theoldjaffa]

On 12/28/2020 at 11:31 AM, q1n3fer said:

Hi all. Need some opinion here. Rims are 18 x 8.5 for front and 18 x 9.5 for rear. Which would you choose?

Option 1
225/40/18
255/35/18

Option 2
235/40/18
255/35/18

Option 3
245/35/18
255/35/18

My ex car was the IS200t

i changed to 18x8.5 ET35 front and 18x9.5 ET45 rear.

Fitted F1A3 235/40 front and 265/30 rear.

works fine and looks ok too.

 

[q1n3fer]

10 hours ago, Theoldjaffa said:

My ex car was the IS200t

i changed to 18x8.5 ET35 front and 18x9.5 ET45 rear.

Fitted F1A3 235/40 front and 265/30 rear.

works fine and looks ok too.

 

nice! just nice flush wor..
but dunno the old is250 can take 265 at rear nt..

[Beregond]

2 minutes ago, q1n3fer said:

nice! just nice flush wor..
but dunno the old is250 can take 265 at rear nt..

my is250 last time all 4 235.40.18😁

[Volvobrick]

20 hours ago, q1n3fer said:

just unsure if 265 would be overkill for is250.. lol!

2.5 NA engine no power to overcome those heavy 265 tyres. End up acceleration will be slower plus worse fuel economy and less comfort. 

[Theoldjaffa]

6 hours ago, q1n3fer said:

nice! just nice flush wor..
but dunno the old is250 can take 265 at rear nt..

265 is fine if your car can take 9.5 at the rear with the correct offset.

impt is the rim. The tyre is just the rubber that wraps around it and 265 doesn’t give a muffin top.

no worries about rubbing as the rear doesn’t rotate like the front wheel.

 

[inlinesix]

5 hours ago, Volvobrick said:

2.5 NA engine no power to overcome those heavy 265 tyres. End up acceleration will be slower plus worse fuel economy and less comfort. 

Acceleration will not be slower.

FC will not be worse.

As long as rim + tyre is lighter than stock.

[Naimed]

On 12/29/2020 at 12:16 PM, Beregond said:

the 250 is orginal staggered already .

nowsaday alot of bmw and merc all staggered, even their SUV come with factory spec staggered. 

Yes and I am thinking of 2 main scenarios in local context (recent 5-10 years):

(a) AD chose to spec the car with larger rims in their local market (going from 16" factory square setup to 17" staggered setup) due to different trim packages or is this a factory top-down decision (marketing, profits, image...etc)?

(b) Sophisticated buyer now have many rims options to choose from when configuring their package or can even go for aftermarket wheels for aesthetic reasons.

So for (a), not sure if there are benefits in terms of driving feel, stability and dry/weather braking...etc for a lux family sedan or AD just want to "up-spec" because other competitors are doing so.

I found the stock rim sizes for some brands/makes in the same category (luxury 4D sedans, ~200hp)

https://www.ultimatespecs.com/car-specs/Lexus/13005/Lexus-IS-(II)-250-Luxury-Aut.html

 

According to the web site below ( https://www.wheel-size.com/size/lexus/is/2008/ ), for Lexus IS250 - different markets received/indent different stock/base rim sizes (maybe due to different trim or package)

USDM specs

EUDM (probably the SG version)

 

Some explanations on the Pros and Cons for Staggered vs Squared: https://www.tirebuyer.com/education/staggered-vs-square-tire-wheel-setups

Staggered

Staggered tire setups are perhaps most common with performance vehicles – for example, Chevy Corvette, Ford Mustang, BMW M3, Mercedes-AMG, Porsche 911, etc. In these vehicle applications, specific staggered tire setups are selected to deliver performance and particular handling balance/characteristics.

As mentioned earlier, staggered tire setups on performance vehicles can help to achieve a desired handling balance, but that balance isn’t necessarily all about outright grip and performance. Staggered tire setups can also encourage a level of handling safety and security.

Staggered tire setups with smaller width tires at the front axle generally produce understeer near the handling limit. Understeer, or a vehicle’s tendency to “push” through a corner, is considered a safer limit handling characteristic than oversteer, which is when the rear of the car breaks traction and moves around during aggressive cornering.

Squared

So in fact, to reduce understeer, neutralize, and optimize limit handling for many performance vehicles, experienced enthusiasts (and GT Sports Car race teams) often move from a staggered to a square tire setup. This is achieved by increasing the tire width at the front axle to equal the rear. Along with producing more front-end grip when cornering, a square tire setup can also positively influence high-speed stability. The front end of the car feels more “planted” because of the greater contact patch.

So what are the downsides to a square setup? When transitioning from a staggered to a square tire setup by increasing front axle tire width, drivers may perceive a decrease in responsiveness to steering inputs. Additionally, not everyone will necessarily find the increased front-end grip and altered handling dynamics comfortable or desirable.

Aside from optimizing performance in some vehicle applications and contexts, square tire setups have another, very practical advantage over staggered tire setups: Front-rear tire rotation, and therefore improved tire longevity. Especially if a vehicle is used in a performance context, the ability to flip front for rear tires, and vice-versa based upon wear rates, is a major practical (and economic!) advantage. And even if your car or truck is not used in performance environments, a square tire setup yields the same rotation and longevity advantages with standard long-term use.

In summary, there is no “right answer” to the question of Staggered vs. Square. It comes down to personal preference, and in many cases there is merit to both. However, it’s more common for drivers to swap from a staggered to a square tire setup, both to change vehicle handling and performance, and to improve overall tire wear and life.

It’s easier said than done, but experimenting with both staggered and square tire and wheel setups is the only way to know what’s preferable for you and your vehicle.