Max tire size without changing the stock offset

[Double]

What would be the biggest tires you can fit front and back without changing the stock offset? My first set of tires has some life left but one day I'll have to replace them so I might look into changing the wheel/tire setup when they are done. Would like to fill out the space a bit more with bigger tires without messing with the stock offset.

Edit:
Current rear wheel 19x9.5J ET52.5 with 275/40/19
Current front wheel 19x9 ET45 with 255/40/19

Sponsored

 

[br_an]

It'd be helpful to know which wheels you have


I found this CJPP video helpful when I was wheel shopping.

 

[Double]

I'll check out the video thnx

 

[kz]

What would be the biggest tires you can fit front and back without changing the stock offset? My first set of tires has some life left but one day I'll have to replace them so I might look into changing the wheel/tire setup when they are done. Would like to fill out the space a bit more with bigger tires without messing with the stock offset.

Edit:
Current rear wheel 19x9 5J ET52.5
Not sure about the front wheels (too dirty to read)

Are you keeping the wheels ? Front is likely ET 45mm and widest you could try to fit is 285 wide tires but it's hard to mount it on 9" wide wheel - 275 is effectively widest you can fit. In the rear you can fit 315 easily with that offset but again you're limited by the wheel width - so 275/285.

 

[Double]

Are you keeping the wheels ? Front is likely ET 45mm and widest you could try to fit is 285 wide tires but it's hard to mount it on 9" wide wheel - 275 is effectively widest you can fit. In the rear you can fit 315 easily with that offset but again you're limited by the wheel width - so 275/285.

Will also change the wheels. Main reasoning behind this question is that keeping the ET the same going bigger on the tires will make them push into the car equally as out.

 

[kz]

Will also change the wheels. Main reasoning behind this question is that keeping the ET the same going bigger on the tires will make them push into the car equally as out.

If changing the wheels, you also have to look at the wheels width and make sure you have clearance to the strut on the front. 275 wide tire fits with 45mm offset, 285 is tight but still fits.

 

[NightmareMoon]

The offset locates the center of the wheel (and tire). If you go wider with tire width (and/or wheel), you're pushing equally on the inside and the outside clearances.

With the right offsets, you can run a 285 easily in the front, usually with a 10" wheel, but the offset will need to be ~35-40.

On the rear its pretty easy to run a 305 tire even, but probably with a 52 offset. You can run a 285 with a 35-40 offset in the rear.

 

[Double]

Looking at pricing and availability I might go

Front 275/35/20 wheels +1” w/e they are now
Rear 295/35/20 with 10” wheels

Nothing too crazy I guess, keeping the stock offset should net me 10mm extra tire on the outside to fill things up a bit. Might check out availability and pricing some more to see if I can go 1 higher still.

 

[NightmareMoon]

Looking at pricing and availability I might go

Front 275/35/20 wheels +1” w/e they are now
Rear 295/35/20 with 10” wheels

Nothing too crazy I guess, keeping the stock offset should net me 10mm extra tire on the outside to fill things up a bit. Might check out availability and pricing some more to see if I can go 1 higher still.

Keep in mind the section width (sidewall to sidewall) will be less than advertised if you squeeze them on smaller than ideal wheels. That carries through to tread to a degree too.

 

[Double]

Keep in mind the section width (sidewall to sidewall) will be less than advertised if you squeeze them on smaller than ideal wheels. That carries through to tread to a degree too.

I have to correct that, I had the wrong width for the wheels as stock
Current front wheel 19x9 ET45 with 255/40/19
Current rear wheel 19x9.5 ET52.5 with 275/40/19

Planned
Front 275/35/20 with at least 10" wheels
Rear 295/35/20 with 10.5” - 11" wheels

Annoying thing is that I need 10mm in the back and 20mm in the front to fill up the gap nicely without overdoing it. But I would have to mess with the setup and change the offset front to achieve this. So i'll have to think about that.

 

[kz]

Annoying thing is that I need 10mm in the back and 20mm in the front to fill up the gap nicely without overdoing it. But I would have to mess with the setup and change the offset front to achieve this. So i'll have to think about that.

Why are you so afraid of changing offset ? Either use (slip on) spacers (with longer studs) that effectively change the offset or get a new wheel (which you were planning anyway - and lots of wider aftermarket wheels have different front offset anyway).

Your current wheels are standard performance pack wheels.

 

[ScottyRyan2018]

I have to correct that, I had the wrong width for the wheels as stock
Current front wheel 19x9 ET45 with 255/40/19
Current rear wheel 19x9.5 ET52.5 with 275/40/19

Planned
Front 275/35/20 with at least 10" wheels
Rear 295/35/20 with 10.5” - 11" wheels

Annoying thing is that I need 10mm in the back and 20mm in the front to fill up the gap nicely without overdoing it. But I would have to mess with the setup and change the offset front to achieve this. So i'll have to think about that.

A 20 x 10 +35 for the front and a 20 x 11 + 50 for the rear with a properly sized tire is a really nice fit / look for the S550.

 

[Rick#7]

Stock wheel offsets are not always ideal for filling out the fender with wider tires, sometimes they're not even centered in the fender. If you're going to change the wheels anyway, just get an offset that puts the tire where you want it for the look you're trying to achieve.

If your goal is simply to move the outside sidewall of the tire 10mm closer to the fender lip, you can achieve that with spacers and longer studs without the need to buy new wheels or change tire sizes. If you want to buy new wheels, you can get them in the same size as stock but 10mm less offset to achieve the look you want and not have to figure out what size tire is going to fit with what offset and wheel width.

In any case, if you simply want to max out tire width (and honestly who doesn't want that ) look at what people are running on road courses. Many of them are on 305 width tires up front but it's been well established that 285's fit easily, however to fit that in front you have to reduce the offset to around 30-36 mm.

 

[NightmareMoon]

Once you start going wider than stock, offset will neccessarily change.

There are about a billion 20x10 ET40-35 and 20x11 ET52-50 hubcentric wheels meant for mustangs that will work . 10.5” wheels are a whole lot less common, but some exist. None of em have stock offsets.

My square street setup is flush with the fenders and is a 10” ET35 wheel with a 285 tire

I also run 315 square on 11” wheels with extra large spacers but thats another story.

 

[Double]

Why are you so afraid of changing offset ? Either use (slip on) spacers (with longer studs) that effectively change the offset or get a new wheel (which you were planning anyway - and lots of wider aftermarket wheels have different front offset anyway).

Your current wheels are standard performance pack wheels.

Don’t want to change the offset for fear of damage to bearings and what not

Sponsored