Running "fronts" (225/40ZR18) on all 4 wheels: how's the fit?

[aurelius]

I like the idea of running the same size tire at all 4 corners. I know the larger, rear tire size works when doing so but how about the smaller, front tire size?

Anyone running this setup or know anything about whether it's viable? If so, do tell.

[danewilson77]

I am running this right now.....cep't mine are 225/45/18.....with spacage.

[aurelius]

Spacers on all 4 or just the rears? What size spacer?

[danewilson77]

3mm up front, 10mm in rear.

Ideal I would have gone 5mm/15mm.

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[mimalmo]

I am running this right now.....cep't mine are 225/45/18.....with spacage.

I thought you were running the BBS wheels, not 4 Style 135's?

[aurelius]

Good point. DW, what's the width on your rear BBS?

[danewilson77]

Good point. DW, what's the width on your rear BBS?

All are 18x8. I guess your question was tire specific to style 135's. I didn't get that in op.

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[mimalmo]

I would think the bigger difference in the "how's the fitment" discussion would be the offset on the BBS versus the OEM wheels.

[zj96sc]

I'm pretty certain the 2nd set of tires my seller gave me is a square 225 setup, but once again not on 135s, making the input probably a little useless.

If you can't get any good input with 135s i'd be happy to get all my numbers for you.

[aurelius]

In my case on the 135's, just wanted to be sure I wouldnt roll the narrower tire off the wider rear wheel but I'm realizing it's a moot point in that the rear wheel is only half an inch wider than the front. Therefore, I don't anticipate any issues.

[zj96sc]

What's your motivation to go 225? Given the choice I wouldn't want to give up the 60mm of rubber on the road, but I'm sure you've got your reasons...just curious.

[danewilson77]

What's your motivation to go 225? Given the choice I wouldn't want to give up the 60mm of rubber on the road, but I'm sure you've got your reasons...just curious.

True.

Could go to a 235 square setup on the 135's.

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[aurelius]

What's your motivation to go 225? Given the choice I wouldn't want to give up the 60mm of rubber on the road, but I'm sure you've got your reasons...just curious.

More neutral handling, at least in theory. A little less unsprung weight, less rolling resistance, ability to rotate (tho not easily). Last but not least, makes the whole tire shebang a hundred bucks cheaper.

[johnrando]

In my recent research on square setups, the most often recommended size is 245/35/18s on the 8.5s, or 255/35/18 if you add negative camber.

[Mike V]

I'm not sure if you'll see an improvement with neutral handling with a 225 stretched on a 8.5" wheel. The only reason I could see doing 225s all around is cost savings. That not-so-common 255/35/18 is expensive. Otherwise, I would put the proper 255 back there. If you want to go square, 17x9 with 255/40/17 works well. The initial cost with wheels can be expensive but tire replacement would be considerably cheaper in the long run.

[mimalmo]

I'm not sure if you'll see an improvement with neutral handling with a 225 stretched on a 8.5" wheel. The only reason I could see doing 225s all around is cost savings. That not-so-common 255/35/18 is expensive. Otherwise, I would put the proper 255 back there. If you want to go square, 17x9 with 255/40/17 works well. The initial cost with wheels can be expensive but tire replacement would be considerably cheaper in the long run.


225mm is not going to be "stretched" on an 8.5" wheel. 225mm is equal to about 8.9 inches.

[zj96sc]

I'm not sure if you'll see an improvement with neutral handling with a 225 stretched on a 8.5" wheel. The only reason I could see doing 225s all around is cost savings. That not-so-common 255/35/18 is expensive. Otherwise, I would put the proper 255 back there. If you want to go square, 17x9 with 255/40/17 works well. The initial cost with wheels can be expensive but tire replacement would be considerably cheaper in the long run.

I think this idea.

[RVAzhp]

don't see the point other than to save money. i'm sure it would fit just fine.

[Rovert]

Since this thread is a few months old what was your decision and how did it turn out?

[aurelius]

Still running the old Pilot Sports on the ragged edge. Dry grip is still excellent but they are incredibly loud. Will report back when I make the tire swap.

[nk_zhp]

I find the car with the square setup to be so much more enjoyable to drive around twisty roads. I think 30mm stagger is too much for a ~240 HP car. I too was looking to reduce my rears to a 235 width to bring it closer to the front. 225 over 8.5 wheels is too stretchy I think.

[Rovert]

I always liked wider rears for public driving just because of unexpected scenarios.

Conditions are so much more predictable on the track with a square setup. You can initiate oversteer or understeer easily and you learn all the bumps and turns of that track so you know what you can do on each corner.

In public I like wider rears since the power is put there and if I am feeling my car right along with understanding the laws of physics, this allows me to be harder on the brakes in a panic situation while cornering with less of a chance of oversteer compared to a same width rear as the front. In a situation that requires me to GET OUT as fast as I can, I can throttle it hard while cornering with less chance of rear tire grip loss. If I understeer it's because I was driving out my front tire traction so it doesn't matter what size is on the rear so long as it's equal or larger. This was my theory and has put into practice many of times because of the unpredictable scenarios the public street has to offer. My car would in no way be in the same condition as it is today if I ran squared in those specific conditions.

There is for still enough RWHP to initiate oversteer even with a wider rear when pushed to the limit. I can still brake oversteer with larger rears too if I come into a sharp, fast, aggressive trail brake. Releasing the brakes gradually will gain back control so long as you didn't hit the brakes so hard you end up in a 4 tire slide. Driving on my square setup now just lets me initiate oversteer much earlier and quicker. Accelerating from a stop (especially with a slight corner) on an uneven surface plays havoc with traction control on a thinner rear tire compared to a staggered setup.

[RVAzhp]

I find the car with the square setup to be so much more enjoyable to drive around twisty roads. I think 30mm stagger is too much for a ~240 HP car. I too was looking to reduce my rears to a 235 width to bring it closer to the front. 225 over 8.5 wheels is too stretchy I think.

i would be interested to see how the 225 fits on the rear wheel. what kind of stretch actually occurs with it.

"Too stretchy"- this got me thinking of Vdub guys, i'm not sure they think anything is "too stretched" on their cars.

[Rovert]

I think it depends on the tire. 225/40/18 on the front 135M wheels looked pretty flush and 265/30 on the rear looked flush when I had those. They were Falken 452s.

[RSPDiver]

For years I've been running (on stock 135s) 235 front with the 255 rears. I went with this for a bit more meat to offset the M3 front sway I installed to limit corner dive. Still a bit of understeer on stock suspension, but crazy flat and managable (with PS2s, for the past 4 years?), and the rims of the front wheels are much more protected. I've been considering a squar rear setup, but my wife drives the car most of the time now, so she may not know how to deal with it in extremes (coming from a Pathfinder). Maybe I need a set of rears to mount for when I drive it? :-)

[johnrando]

For years I've been running (on stock 135s) 235 front with the 255 rears. I went with this for a bit more meat to offset the M3 front sway I installed to limit corner dive. Still a bit of understeer on stock suspension, but crazy flat and managable (with PS2s, for the past 4 years?), and the rims of the front wheels are much more protected. I've been considering a squar rear setup, but my wife drives the car most of the time now, so she may not know how to deal with it in extremes (coming from a Pathfinder). Maybe I need a set of rears to mount for when I drive it? :-)

Does your wife drive it to the limit/edge? If not, squares will be fine for when you drive it. I'm switching mine to squares.

[RSPDiver]

If by "limit" you mean daycare, work, and the grocery store, then yes! :-)

I guess my objection is mod dollars on a car I drive maybe one day a week. Yet I still love the car enough that I want to go FI with it? Lottery is what I need.

[Stu]

My car is set up this way, and I did not even realize it when I bought it. My handling is superb. When I got my wheels refinished, the guy noticed that two tires were a bit more difficult to take off the rim. He said it was because they were the wrong size and should have been wider.

I have since switched back to the staggered setup, only because that is what the manual calls for. I'm kinda a "follow the manual" nut ;)

[Smolck]

Not sure if this is really helpful but I just got a set of 235/40/18's for the rear of my car. They fit great and give a little more sidewall which I like. I bought this car less than a month ago and it had 4 almost brand new Michelins on it. Thanks to a pot hole and bad luck, I have had to replace 3 of them.

[nike001]

Since you're going with a sidewall thats a bit bigger than stock spec, I'm unsure if this would affect your speedo or not.

My contribution to this thread is that today I saw a ZHP with 225 all around on stock spec rims (8"F & 8.5"R) and the rears looked a bit stretched. Definitely not noticeable unless you're looking for it. If anyone is in my area, I'll gladly trade you my 8" fronts for your 8.5" rears. I've been looking to run 225 squared.

[Smolck]

Since you're going with a sidewall thats a bit bigger than stock spec, I'm unsure if this would affect your speedo or not.

My contribution to this thread is that today I saw a ZHP with 225 all around on stock spec rims (8"F & 8.5"R) and the rears looked a bit stretched. Definitely not noticeable unless you're looking for it. If anyone is in my area, I'll gladly trade you my 8" fronts for your 8.5" rears. I've been looking to run 225 squared.

BMW's get their speed from the wheel speed sensors, it matters not how tall of a tire you use. Same reason why a diff swap doesn't throw off your speedo, in old cars that are controlled by a gear in the trans it would, but not the E46. But interestingly standing side by side the 235/40 is almost the exact same height overall as the 255/35. I'm talking millimeters in difference, if any at all.