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[Tykar]

I've been through the Aggressive Fitment thread (it's huge now), but can't find what I'm looking for. Hopefully someone out there can help. I need to get new tires and am trying to figure out if I should consider different sizes. Here is what I have currently:

Eibach Pro Springs
VMRv710 Wheels: 19"x8.5" 20et front, 19"x9" 22et rear.
Currently have 245/35/19 front, 275/30/19 rear
Looking to put PS4s on the car.

What are the max sizes I should consider and is there any advantage to going wider/taller in front or back?

Will a 275/35/19 work fine in the rear? Seems like it will bring the rear back closer to the OEM spec on diameter than what I have now. Might also help with a little more cushion in the larger sidewall (road comfort).

Car will never see the track, so it's street driving only. Most of my driving is on local roads, not highway.

Thanks in advance.

[M3SQRD]

Somewhat limited with the 8.5” wide F and 9” wide R. A 255/35 F and 275/35 R should work on the widths you have. In running 18x9.5et22 and 18x10et17 with 275/285 and things fit fine. Have three sets of HRE R40 and R43.

[TboneS54]

i wouldn't use those weheels, but stock 245/265 would be best.

[M3SQRD]

Originally Posted by TboneS54

i wouldn't use those weheels, but stock 245/265 would be best.

It’s not as easy for people to swap wheels and it’s easier to run slightly wider tires on a given set of wheels without issues. PSS * spec 255/35 Fiona 8.5-10” wide wheels , and 275/35 fit on 9-11” wide wheels so the 255/275 will fit and were common sizes used starting back in 2009-2010. Optimized for the sizes no but it’ll work just fine and without tires substantially wider than the wheels. Due to inner and outer lip designs, actual wheel width is 1” wider than measured spec; e.g., a 10” wide wheel has an actual 11” total width.

[MineralWhiteF80]

What are the max sizes I should consider and is there any advantage to going wider/taller in front or back?

The correct sizes for those wheels is a 245/35/19 front (XL, non star spec) and 265/35/19 rear (mercedes M01 spec), which gives you the best tire width for the wheel width while keeping the same front to rear overall diameter ratio as the OEM fitment.

The widest tire I would go is the front 255/35/19 PS4S Bmw star spec that has the 9.5/32" tread (not the 9/32" tread option) and for the rear, the 275/35/19 PS4S XL (not SL, not star spec). This gives you a wider option while sticking with the correct front to rear tire diameter ratio. ALSO KEEP IN MIND, the front 255/35/19 is 26" tall and that will lightly rub your fender liners!

Will a 275/35/19 work fine in the rear?

It depends on the specific 275/35/19 tire, some are far too wide, some are too narrow! In the Michelin PS4S tire specifically, you can run any of the five variations, but some will be slightly better for your taste of 'widest tires possible.' But that still doesn't mean they will perform any better than the 265/35 size.

Currently have 245/35/19 front, 275/30/19 rear

That is not a good combo because the diameter of the rear tire needs to be 0.5—0.6" larger than the front tire. A 275/30 is actually smaller diameter than a 245/35.

In general, some important things to consider:

1) Don't use the 'standardized' numbers on the side of the tire to determine the correct sized tire for a wheel width because there might be five+ different "275/35/19" sizes of one tire model that all have different actual sizes and tread patterns. For example, a 245/35/19 Michelin PSS BMW star spec is actually wider tread width than the 255/35/19 Michelin PSS BMW start spec (but the PS4S tire is not). You really should be looking at actual tread width (not section width) specification of a tire, and then matching it as closely as you can to your wheel width. That is really best, even though it may reduce bragging rights to the uninformed car enthusiast, or not give you that fat ass meaty look.

2) Tires that have tread width equal to measured wheel width (bead mating surfaces, not overall outside width), or even better, tires that are slightly stretched on the wheel provide the best handling performance. Track guys run 275 tires on 10.5" wheels. Only street driving, you likely would not explore even close to 100% traction capability to really care about the 'limit.' so having "maximum traction" doesn't really even apply here.

3) Tires that are too wide for a wheel provide worse turn in and feel more squirmy. Wider tires generally offer more lateral traction when on the appropriate wheel width where as taller/softer sidewalls offer more straight line traction. Buying wider tires with the expectation of getting more straight line traction isn't the best thought process, especially when we are splitting hairs at best in terms of actual tire width.

[Tykar]

Thanks for all the comments. Very helpful.

Just to clarify, the tire/wheel combos I have currently came with the car when I bought it (existing tires are Pilot Super Sports). I always thought it was odd to have the smaller rear diameter wheel, but I'm guessing it was to level out any potential positive rake for the car. I'm not looking to change wheels. I was just curious what the collective experts recommend when I get new tires since I don't have a clue.

Again, appreciate all the help.