prehayem

2.7T As we know has the big 4 pad brake calipers on the front wheels.

Just bought a set of 18x8 ET 35 rims W/ 5mm Spacers & Lugs (spacers only for the front wheels)

Stock rims were 16x7 ET 45 & appeared to have a 5- 10mm space for the calipers.

Last night I went and put the spacer and rim on the hub for fitment verification before I have tires mounted ( I didn't put the hub centric rings on, if that adds a mm or so I dunno)

According to my math, the actual size is something like ET32 (with 8 inch wide rims). So in theory, with these 5mm spacers I should have 3mm clearance. It appeared to be about that (tiggggghhht squeeze) Brake pads and rotors are fairly new.

I hate being wrong! Was hoping someone has more insight before I get these tires mounted

(Will be getting 245/40/18 tires, I know it's a lil wide, I kinda want that aggressive stance)

SloopJohnB@mac.com

The issue as you've found out is generally the clearance between the caliper and the spokes, not the rim. ET isn't always the issue, it's the design of the spokes…generally the spokes need to be somewhat concave on the inside. 3mm is really tight, I'd prefer 5 but as long as you have 3, worst case is the calipers may knock slightly on extreme cornering or with brand new pads and rotors. Figure worn rotors (and they're ALL worn after 2-3K miles) at 1mm wear limit…new rotors push floating calipers out and HP2 are floating calipers. New pads, same story.

prehayem

I meant the spokes of the new rims clearance. I'll probably buy some 7.5 - 10mm spacers for when I change the front brakes next. I'm just royally concerned that I am 100% incorrect :/ and it's not going to fit at all.

Well I have seen many posts for those of us with 2.7T & aftermarket rims go unanswered. I'm just going to actually bolt the rim on to double check, if my second go passes the tires are getting mounted. If anyone else with a 2.7T has put on 8 inch wide rims on let me know!

SloopJohnB@mac.com

PS..the hubcentric rings shouldn't affect offset at all. They go into a recess in the wheel hub and mount flat on the axle hub…no change.

bmlee007

It's about the shape, thickness and concavity of the spokes, as well as the offset. I ran a set of 18x8 et42 RS4 reps on my 2.7T with no brake issues at all. Even when I installed new pads and rotors, there was plenty of clearance. The problem I had with that offset was that the inside edge of the tire only had about 6mm of clearance to the spindle.

GTA_Driver

What rims did you buy? Also, if you will be running spacers at the front, be sure to run them in the back as well. Otherwise that is just weird.

Where is the tight squeeze? By the upright or the brake calipers?

The new wheel offset is ET35. That's extra 10 mm outboard. But they are 25.4 mm wider, or about 12.52 mm on each side (if the offset remained the same 45 mm as your old 16" rim). But because the offset is an extra 10 mm outward, the wheel effectively is 2.52 mm closer inward and 22.52mm closer outward compared to your factory 16" wheel.

With the new rim you should still be able to run it without the use of spacers, I would think.

If you add a 5 mm spacer, then your inner distance between the wheel and the upright will grow by 2.48 mm compared to the old rim, and the outboard side will extend 27.52 mm further out than your old rim.

Some models came with sport wheels that ran 235 width tires. 245 is marginally wider so you'll be fine.

prehayem

@ GTA_Driver lol! I never thought about it like that. But, would that actually throw the balance/alignment off? Here are the rims I got:

http://www.ecstuning.com/ES2703512/

The offset calculator you used is the same way I figured these numbers out. The wheel well flares out on our cars almost 30mm, so it wont stick out too crazy looking.

@bmlee007 & SloopJohnB@mac.com you guys couldn't be more right about the actual design of the rim. The rims might have fit without spacers, but the spokes are set up angled like a fan blade. The highest part is 10mm away from the caliper & the lowest 3mm. Guess it was pure stroke of luck that I bought the spacers!

So in conclusion, if changing rim width from 7 inches to 8 inches and the offset of the 7 inch rim is ET45, you will need (in most cases) to get an offset of ET35 for the 8 inch rim.

Largest determining factor in aftermarket rim fitment is the design and clearance for the spokes.

Thanks guys that was a lot of good info! I am paranoid so I put all 4 rims on and put the car in neutral (on a lift) and spun them many times before agreeing to let the tire shop mount the tires on them ahaha.

GTA_Driver

Except I did not use a calculator, and you had different numbers.