wheel offsets

S13 Slide

Driver
I'm Bored so I thought I would make a wheel offset thread for all your noobs. :D

Ok, so lets start with an easy one:
15x7 +0 offset
you start with dividing the wheel width into two which is 3.5 inches.
+0 offset means 3.5inches outward and 3.5 inches inward of the wheels hub, perfect center of the wheel.
*****Good formula to remember is 25.4 milimters equals ONE INCH******
so you multiply 25.4millimters x 3.5inches = 88.9mm's
so the 15x7+0 offset wheel is 88.9mm's outward and 88.9mm's inward from the wheel hub.

Now another example is 15x7+40offset
Again start with the center of the wheel width in millimeters which is 88.9.
Now since its a POSITIVE 40mm's you ADD 40mms to 88.9 which is 128.9 mm's INWARD from the center of the wheel.
To figure out the outward part of the wheel you subtract 88.9 from 40mm's which is 48.9mm's OUTWARD of the center of the wheel.

For Negative Offset wheels:
Again you start with the center of the wheel width(88.9mm's), lets go with 15x7 -15offset.
you do the exact opposite of a positive offset wheel and visa-versa.
To figure out the outward part of the wheel you ADD 88.9mm's + 15mm's = 103.9 mm's
To figure out the inward part of the wheel you SUBTRACT 88.9mm's - 15mm's = 73.9

Stock S13 wheel are 15x6+40 offset
wheel width in milimeters: 152.4mm's
Direct center of wheel: 152.4m's / 2 = 76.2
Since its a POSITIVE 40 offset you SUBTRACT 40 to the outward width of the wheel:
so 76.2 - 40 = 36.2mm's
To figure out inward part of wheel you ADD 76.2 + 40 = 116.2
Coming OUT from the disc brake hub Equals 36.2mm's towards the fender
Coming IN from the disc brake hub equals 116.2mm's towards the strut.

Now to figure out how 15x7+0offset wheels are going to stick out and stick in towards your struts (if the are) you get your stock millimeter measurements you just made.
which is 36.2mm's outward and 116mm's inward, now compared to the stock wheels the 15x7+0 offset wheels are going to be:
88.9(15x7+0 offset wheels outward in mm's) - 36.2(stock S13 wheels outward in mm's) =
52.7mm's farther out towards the fender from the stock wheels.
116.2(Stock 15x6+offset wheels inward in mm's) - 88.9 = 27.1 the 15x7+0 offset wheels are acctually going to stick out farther outward from the strut then the stock wheels do by 27.1 millimeters.
Basically the 15x7+0 offset wheels are going to be 52.7mm's farther out towards the fender and 27.1 mm's farther out from the strut, its a very good offset for the S13s kwKouki had it and it looked very nice.

It really comes down to really really basic math just adding and subtracting. It's might be hard to understand in words. But if your still stumped just use this web site to figure it out
:

Wheel Offset Calculator
 
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S13 Slide

Driver
No problem....i might make another post about backspacing thats harder to understand though....also coilover clearance mith....IMO
 

S13 Slide

Driver
well having a big lip all depens on the wheel and also the offset....you can have a high offset and have a huge lip you can also have a low offset and have a small lip and visa vesa is all about the wheel manufactor and how they wanted it too look.

Offsets are the easy part of a wheel, backspacing get alittle more technical.
 

SileightyBoi

Retired Drifter/Stoner
Driver
S13 Slide said:
well having a big lip all depens on the wheel and also the offset....you can have a high offset and have a huge lip you can also have a low offset and have a small lip and visa vesa is all about the wheel manufactor and how they wanted it too look.

Offsets are the easy part of a wheel, backspacing get alittle more technical.
dood when i need the calculation ima let u kno ;)
 
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