running a 9.5 in the front with a meaty tire on stock struts is just more hassle than its worth and as you saw from king tuts post on the first page, the clearance is incredibly tight and to make it work you really gotta pull that strut in and have a really low yet stiff spring. This is why those going to springs should really stick with the 17x9 +35-ish formula with a 245 tires. That is a spot on fit for htese cars and is more than plenty of tire for the car given you run something decent and not nakangs or other garbage.
if you're asking about 2mm difference, you've got some reading to do man. read and comprehend what people are telling you and what others wrote in here. if you're already on coilovers you will be fine. you may rub on hard dips and like i said in my first post YOU WILL RUB ON THE REAR BUMPER COVER TABS so dremel that shit off or let the tire do it for you.
what kind of 255 tire are you going to run? not all tires are created equal.
if you don't want to roll rear to run minimal camber go to -2.2 front and -2 rear if you can even adjust the rear. make sure who ever does the alignment toes in the rear. Total toe in .18 roughly. Keep in mind that your rear is not adjustable camber factory so you will need an LCA if you want to fix that because as you lower the rear it will camber in-i highly suggest SPC, but if you want to spend money then go SPL. Those are my only two recommendations just because i've seen so many and know how pain in the fucking ass it is to adjust arms like the cusco for example.
i dont think alignment stuff was posted in detail in this thread before so here is a quick explanation of how things basically work on this car and generally on all cars in terms of geometry. Keep in mind we have McPherson strut front and double wishbones rear. i'll explain why i talk about more camber up front, less camber in rear and toe in rear, toe out front. i should probably copy this into the OP.
so camber...basically in order to maximize cornering force from your tires, the tire must be square on the road
during a corner to achieve max grip. If your car had zero camber (all tires square to the road when driving straight), as soon as you turn, the body will roll to the outside, and the outer tires will roll only on the outsides of the tires. Thats why if you ever drove a car with stock alignment hard in turns, you'll see the outsides of the tires worn.
Because of the twin's suspension geometry. Simply put, as the car rolls in a turn, the outside wheels' suspension compresses (makes sense right?). The rear suspension was designed to gain negative camber as it compresses. So as the body rolls, the tire does not roll over as much as the car's body roll, maximizing the tire's contact patch. The front suspension is different, it does
not gain significant negative camber as it compresses (during body roll in a corner), and therefore allows the tire to roll over to the outside edge, minimizing
traction. This is why you must give the front end more negative camber to begin with. (Another very popular BRZ trick is to run a stiff front sway bar, to limit the front body roll and maximize tire contact).
now toe..Toe-in will stabilize the car, making it track straight and not want to change direction. Toe out does the opposite, makes it twitchy, and want to change direction quickly. A car is more responsive with toe out, but significantly less stable. Just a basic definition.
FRONT Of CAR - Toe-out in the front lets the car turn in nicely, but may "tramline" down the road (finding grooves and irregularities and following them). Toe-in front makes the car hard to turn and want to "push" or understeer. I suggest going with total toe out front of -0.1 (so about -.05 per side)
REAR OF CAR - Toe-out in the rear is pretty dangerous for RWD cars, makes the car want to spin, especially under hard braking. Toe-in rear will keep the rear stable, and (here is the key) allow for you to put power down as early and as hard as possible without wheel spin. More is not always better, racers will always adjust these settings till they get it just right. For the street, the suggested settings will let you set-it-and-forget-it. Negative camber does not kill tires. Negative camber plus excessive toe (in or out) causes inner tire wear. Toe (in or out) in effect forces the car to "drag" the tire down the road, where 0 toe lets the tire roll down the road. Make sense? Negative camber will cause the tire to roll on the inside of the tire, but negative camber plus excessive toe will drag the inside of the tire down the road causing bad inner tire wear.
TLDR: yes 255/35/18 on 18x9.5 +38 will fit just fine with coilovers. i now have no wheel gap all around and i'm perfectly fine. no rub no drama. But i'm rolled in rear and did alot of triming to rear bumper. If anyone is in NJ drop by @
AZP Installs and i'd be happy to show you around the car.
-Ivan
