Help-wheel questions

CivilPenny

I’m looking to grab some new wheels for my Sport package Z (includes the bigger brakes) and I have NO clue how to go about it. I’d like great fitment, but am unsure how wheel measurements work, and what will fit. I know I need to clear the calipers, and fenders. Is it possible to find wheels like such without using spacers or heavy modification? Can I have 3 piece wheels or only ones without lips? Any help is appreciated. Thanks everyone!!

bunk

Browse the Will it fit? sticky post in the wheels section of the forum.

Google: wheel offset site:the370z.com and youll find everything you need to know.

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Rusty

Just ask OptionZero. He'll give you an ear full and then some.

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OptionZero

Learning about wheel sizing is something you can do on your own. Wheel size cannot be considered without tire size.

First, a disclaimer:
You're gonna need to spend money. There's no wheel setup anyone here can recommend that will look good on a stock car with stock suspension. The car is too high, it's going to look like ****. Anyone that tells you otherwise was too cheap to do it right and is trying to make themselves feel better.

If you don't wanna spend money, keep your stock wheels and roll like the car came out of the factory. No shame there, and it's better than doing it wrong.

Onwards.

The simplest approach:

Read the threads on wheels pinned atop this section. Find one you like. Show us. We'll tell you how to copy that. No thinking required, just your credit card and the appropriate retailers.


The proper approach:

Learn how wheel fitment works. It's not hard. Follow along.

Every wheel has a diameter, width, offset, and bolt pattern, expressed typically like this:
18 (diameter) x 10.5 (width), +18 (offset), 5x114.3 (bolt pattern)

You need 5x114.3 bolt pattern. Not negotiable.

Folks run anywhere from 18 to 20 inch diameter. For aesthetics, 20s are optimal because the wheel arches of our car are quite large. The compromise is that 20 inch wheels are more expensive. 20 inch tires are more expensive. Pay to play.



This example has 20's. The tire is slightly tucked under the fender. The arches are completely filled up.

18 inch wheels are cheaper and lighter, with a greater range of options, and an accompanying cheaper and wider set of tire options to go with that. They will not look good but they will work. Track folks all run 18's for cost effectiveness and wider tire compound selections.

Example:


Alwakra's car has square 18x10.5, +18 CE28N's with 275/40/18 tires and tracks his car regularly. This is an ideal wheel setup for that purpose. It does not look good.

19's offer a compromise, to a degree. Tire selection does not approach 18's. Price leans closer to 20's. Visually, better.

Next, width and offset. These two aspects cannot be considered independently of each other as they affect how the wheel sits in the wheel well.

Width is self explanatory. It's how wide the wheel is.
Offset is the orientation of the wheel relative to the hub (mounting surface for the wheels. The more higher the offset is, the further inward the wheel sits. A lower offset wheel will sit further from the hub, and stick out from the fender.
Example:
This red car has stock nismo wheels, 19x9.5 +40 in front and 19x10.5 +23 in rear


This white car has TE37's, 19x9.5 +22 front and 19x10.5 +12 in rear


Compare how the wheels fit each car. They have the identical diameter and width, but but the white car has lower offset wheels that sit further away from hub, closer to the fender "outward."

Same width, lower offset = wheel sits further outward
Same offset, wider = outside edge also extends further outward.

That is how width and offset work; however, knowing the concept is relatively worthless without practical application to this car. Fortunately, the white car above illustrates a fairly standard drop and wheel size. That is a standard size for TE37's that any vendor would recommend you out of the box. You can fit it without too crazy and alignment, any many people have simply installed lowering springs and that size wheels and been "ok"

The more aggressive approach is to run even wider and lower offset wheels, with coilovers or air suspension that bring the car lower to the ground. This requires rolling your fenders (really not that bad, like $100 most places), as well as custom alignment achieved through adjustable suspension components. That is more work but lets you do much more, like be cool like this guy and run 20x11 +15, 20x12 +20:

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vtec to vvel

Just don’t verbally attack him lol that’s a different ball game. It’s okay to disagree with him (I think?), but be mature about it.

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vtec to vvel

Optionzero, how do you feel about 14’s on the Z? Kidding bro.

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Rusty

Sometimes he's like 36 grit sandpaper. A bit rough...........really rough.

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bunk

Dont forget to say thank you to OZ OP!

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vtec to vvel

oh boy, now you're gonna get it. i'd run if I were you. time to re-register under a different username and start fresh lmao

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OptionZero

There are free tools that help you do math regarding offset and width:
https://www.1010tires.com/Tools/Wheel-Offset-Calculator

Just input the width/offset of the current wheels and whatever size you'll considering and the calculator tells you how it will set relative to your current size

Now, let's talk about tire size

Tire size involves width, aspect ratio, and diameter, expressed normally like this:
315/25/20
315 is the width in MM
25 is the aspect ratio in PERCENTAGE of the width
20 is the diameter in INCHES

Don't ask me why there's different units or why they use a ratio, some clown decided thats the format and thts what we got.

Width and diameter are self explanatory. Aspect ratio is how "thick" the tire is vertically; think of it as how fat a donut is. The confusing part is that it is measured as a percentage of the width, so in a 315/25/20 tire, the aspect ratio of 25 means the the tire thickness is 25% of 315. It's stupid. i know

All that really matters is that this affects how tall the tire is. Fortunately there is again a free tool that does the math for you:
https://tiresize.com/height-calculator/

This tells us that a 315/25/20 tire is 26.2 inches tall

Why is this relevant? Because your front and rear tires need to be about 3% of each other (i think) for your speed sensor to work; going too far will trip warning lights.

A secondary reason is gearing. A taller tire will physically take more power to spin; this is generally bad; conversely, bigger wheels will in theory change your top speed.

The third reason is probably the most relevant to most people - how tall a tire is affects how it looks and how it fits in the wheel well.

The stock tire wheel diameter for a Nismo is 26.7 inches in front, 26.9 inches rear. Going bigger than that will visually fill out the wheel well, but depending on the height of the tire and stance, you aren't going to look better that way. It lends a 4x4 monster truck appearance. Going too small will create a gap, which is also bad. You generally should stay roughly close to the stock height of the tire

Stock wheels are 18 (base) or 19 (sport/nismo) They maintain the same height despite different diameters by changing the height of the tire. Again, use the tire height calculator to do the work for you if you're switching between 18/19/20

Next, we should examine the concept of "stretched" tires. Ignorant folks will recoil at the idea because they were raised in a different car culture. It is not a bad thing by itself, but like all things, too much can be dangerous.

Every tire manufacturer recommends a specific wheel width (or range of width) for a specific tire size. For example:

https://www.toyotires.com/tire/patte...res-proxes-r1r

Scroll down to say, 265/35/18 on this Toyo R1R. They recommend between a 9 or 10.t inch width wheel for this size, with a 9.5 width as their "ideal." Every manufacture, despite adhering to the same tire size format we discussed above, has slight differences in how their tire fits a wheel; there's nothing you can do about it, it's just the process.

Stretching a tire means putting a tire that is narrower than the "normal" width for a particular width tire.

For that same 18x9.5 wheel described above, a tire that is less than 265/35/18, would be considered by many people, a "stretched" tire. Putting a 225/45/18, for example, is much more narrow a tire than is normal for that width wheel and would be "stretched" tire sizing.

Why do people do that? To create more room for a tire to clear the fender. Example, 265/35/18 on an 18x9.5 wheel:

This would be considered a normal or "square" tire fitment.

Now look at at 225/45/18 on the same 18x9.5 size wheel


Look at the difference in how the tire size on the wheel. The additional space created by now the tire shoulder angles inward is space needed to fit under a fender.

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justin_boy

if anyone ever wanted to know anything about wheel sizing in our cars....show them this thread

Rusty

Aaaah......I got thick skin.

OZ has good info for rims. He just needs to soften his touch a little sometimes.

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Zezus

This legit needs a sticky. You see these questions asked all of the time on here. OptionZero did a great job of explaining what all the numbers mean, and even provided examples. Well done sir.

sx moneypit

OptionZero

Lastly, let's talk about camber. This diagram illustrates what camber is:



Camber is the "tilt" of the wheel, measured in degrees. 0 camber is a wheel that is straight up and down. As the top wheel moves inward, the measurement is a negative number; if the top of the wheel moves outward, the measurement is positive.

Folks freak out whenever camber is not 0. These folks are stupid. Negative camber is not bad. Negative camber does not "increase" tire wear. Negative camber helps a car turn; how much camber is good depends on your suspension and the type of driving you're doing. There's basically no situation when positive camber helps. Most cars will operate better with more camber in front. Negative camber will cause "uneven" wear (as more weight is put on the inside of the tire), but it doesn't really cause the wear to occur faster. Another alignment setting, "toe" is the actual camber killer when done excessively

Example:


Not a perfect example due to the exotic suspension, but look at the extreme negative camber of this Formula 1 car. They turn so hard and so fast in part due to camber (and many other factors). The point is simply that camber can be good when appropriately measured.

Forget this performance bullcrap tho. Camber is essential for wheel fitment when combined with the proper height, wheel width, offset, and tire size.

Consider Wiggin's old setup:


This is a front wheel setup of 20x10.5 +24, with a 285/35/20 tire, which a much more aggressive wheel spec and much wider/taller tire spec than stock (which is 19x9.5 +40, 245/40/19). How does he cram all that under the fender? Negative camber, which pushes the top of tire inward so it can clear the fender.

Wiggins is an unusual setup because he is running such a tall tire; he was forced to by a Toyo sponsorship. Nonetheless, it illustrates what is possible with the appropriate alignment - thats a pretty fatass tire, not much stretch, and it fits




CarbonFZ's white Z is probably a more practical example. I believe those the first pic is Work Meister, 19x10 +10 in front, or more aggressive. I forgot the specs of his white faced 20x10 VSXX. You can see the stretched tire and negative camber that allows him to clear the fender. He's running a static set up, so that height is what he drives at.

Again - you should know the general concepts of wheel size, tire size, and camber. As a practical matter, study what folks have done before so you get a ballpark of what is possible with what type of work.

In general, aggressive wheels require a simple formula:
Coilovers to adjust height
SPL Parts suspension arms to adjust camber and other settings
Aggressive wheel size
camber and tire to fit

(you should also roll your fenders. Pay a guy $100 and it'll be done)

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