Alright so about a few months ago, I purchased a Mazda 6. Well I just bought a set of rims for it. I am completely new at cars ao I am just hoping they will fit. I plan on putting a new set of 17" rims on the stock tires. I know the stock rims have an offset of 60 mm, so I really have no clue what that means. All i know is that the rims I purchased are: 17 x 7.5 Black / Machined 5:100 / 5:114.3 42mm offset...So I am planning on just putting these new rims on the stock tires. My question is, will these fit and do I need to purchase anything else like valve stems and wheel locks or bolts and stuff like that?

 

well the stock tires are 16's and the new rims are 17's so you will need new tires to fit your rims

what type of rims did you get, where did you get them?

get us all the specs on the rims
how many lug nuts, the space between them
the offset how wide the rim is

 

He answered all of that

5 bolt, dual pattern 100mm 114.3mm spacing
7.5" wide
42mm offset

Your stock 215/50R17 should work fine on the 7.5" wide rim.

Those rims would stick approximately 1" (25mm) further out per side (from the wheelwell) than the stock 17x7 60mm offset wheels you have now...Go out to your car and measure and see if you have the extra inch to work with.

52.5mm offset is ideal with a 7.5" wide rim. I'm not saying those won't work, just that I think they'll rub. (There have been a few of these threads lately.)

 

So what exactly do I measure on my wheel. I know absolutely nothing about this stuff ...From one side of the wheel to the other?
Yea and BTW: My stock tires are 17"

 

sst means to measure the gap from the tire edge (sidewall) to the innner fender edge , to see how much left to play with from left to right (not up/down)

your wheel is .5 wider , do you have that play

 

I added in the addtional 0.5" when I figured out the above calculations.

The measurement you are looking to take is cross-car (from left-right in-vehicle.)

Basically, the outer edge of your wheel/tire combination will move out toward the fender by 1" on each side....Here's how I calculated it so that you understand

17x7" rim, 60mm offset (17" diameter, 7" width, 60mm positive offset)
7 in * 25.4 mm/in =177.8mm, 3.5" (to determine centerline of the rim)= 88.9mm

With a 60mm offset (positive number means the mounting surface of the rim is outboard (further from vehicle centerline)

88.9mm-60mm = 28.9mm.

This means that from where the surface that your wheel mounts to on the hub, to the outer edge of the rim is 28.9mm, the tire protrudes a little bit further out than the wheel. (maybe 1/4")

17x7.5" rim, 42mm offset
7.5*25.4=190.5mm.....3.75"= 95.25mm
95.25mm-42mm - 53.25mm

So the difference between your current rims and the rims you are looking for is:
53.25mm-28.9mm= 24.35mm (25.4mm=1 inch)

In other words, the new rims would sit an additional 24.35mm towards the fender. I don't think you've got a full inch of clearance per side. (my opinion.)

Take a ruler and place the end on your tire, and measure how much clearance you have between the outer edge of the rim and the inner edge of the fenderwell (imagine your tires compressing up into the wheelwell during suspension movement.) Or better yet, jack up the opposite corner (if you are checking clearance at Rear left tire, then jack up the front right corner of the vehicle.) This should compress the suspension some to get the tire into a better position to check clearances.

Don't forget that the front suspension needs to be able to compress while turning.