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hollywood

What Offset? - The Complete Wheel Guide

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Before everyone is about to tell me to hit the search button, its not one of those threads. This thread is intended to help eveyone else out there when they're about to buy or considering some new rims.

 

What I want is for members to post what what rim size and offset they have and any issues you've encountered.

 

[b]S15[/b]

16 6.5 +45 Stock

16 7 +29 Recommended by Taka Kaira

16 7 +33 Front Recommended by Rays/Nismo

16 7 +35 Recommended by Work

16 8 +38 Recommended by Taka Kaira

16 8 +45 Rear Recommended by Work

17 7 +30 Recommended by Taka Kaira/Rays/Nismo

17 7 +31 Recommended by Work

17 7 +35 Recommended by Work/Rays

17 7.5 +30 Front Recommended by Rays

17 8 +38 Recommended by Taka Kaira/Rays/Nismo

17 8 +44 Rear Recommended by Rays

17 8 +45 Rear Recommended by Work

17 8.5 +40 Rear Recommended by Rays

17 9 +10 SpecS15

18 7.5 +30 Front Recommended by Rays

18 7.5 +31 Recommended by Taka Kaira

18 7.5 +32 Recommended by Work

18 7.5 +35 Recommended by Work

18 8 +36 Recommended by Taka Kaira

18 8.5 +40 Rear Recommended by Rays

18 8.5 +45 Rear Recommended by Work

18 8.5 +30 Front SpecS15

18 9.5 +30 Rear SpecS15

18 9 +30 SpecS15

18 9.5 +12 SpecS15

18 9 +22 Front SpecS15

18 10 +25 Rear SpecS15

 

[b]S14[/b]

16 6.5 +40 Stock

16 7 +31 Recommended by Taka Kaira

16 7 +33 Front Recommended by Rays/Nismo

16 8 +31 Recommended by Taka Kaira

16 8 +35 Recommended by Work

16 8 +38 Rear Recommended by Rays/Nismo

17 8 +25 Front nismoS14: sit even with guards

17 8 +31 Recommended by Taka Kaira

17 8 +36 Front Recommended by Rays/Nismo

17 9 +35 Rear nismoS14: sit a little out

17 9 +38 Recommended by Taka Kaira/Rays/Nismo

 

[b]S13 / 180SX[/b]

16 7 +32 Recommended by Taka Kaira

16 7 +33 Front Recommended by Rays/Nismo

16 8 +32 Recommended by Taka Kaira/DumHed: stuck out to far

16 8 +38 Rear Recommended by Rays/Nismo

17 7 +35 Recommended by Taka Kaira/InitialSteve/DannyG

17 7 +38 PS13boy

17 8 +22 Front RHiSC

17 8 +30 Front 180athid

17 8 +35 Recommended by Taka Kaira/InitialSteve/DannyG/Midori

17 8 +36 Front Recommended by Rays/Nismo

17 8.5 +35 Front pitchd

17 9 +30 Rear 180athid

17 9 +40 Rear Mark/Midori

17 9 +38 Rear Recommended by Taka Kaira/Rays/Nismo

17 9 +47 Rear RhiSC

17 9.5 +35 Rear pitchd

18 8 +20 Front 180athid

18 9 +20 Rear 180athid: shreds tyres

 

As you can see I started to gather others specs but 90% of the time all i found was 'will these fit'. Not the rims actually fitted to cars.

 

Some useful links also.

 

Offset Calculator

Tyre Calculator

Quick Tyre Reference (has a neat table at the bottom of the page for rolling diameters)

 

offset.gif

 

Also if any of the specs above are wrong just let me know and i'll edit. ;)

 

 

**EDIT**

 

This is also some very usefull info as supplied by redleg6

 

Taken from thread Help me with Offset!

 

Great stuff redleg6 ;)

 

inside of wheel post-38-1108807990.gif outside of wheel

 

so what this all sounds like is that the less the offset is, the more the wheel will stick out...right?

 

as the wheel sits on the hub, the distance is decreased, therefore the offset will be less...i think

 

http://www.wheelmart.com/spinon.htm

 

http://www.rsracing.com/tech-wheel.html#backspace

 

http://www.chris-longhurst.com/carbibles/i...tyre_bible.html

offset.jpg

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This was a very good thread to start as alot of people dont have a clue about offsets and just buy rims without thinking about it.

 

I did a heap of research on this before i got the rims on my car and as im sure you know there are alot of factors that come into it when upgrading to a larger wider wheel/tire combination!

 

id give you my findings but there for a prelude so pretty pointless on this site! :D

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Great idea.. I think it deserves to be a sticky.

 

BTW, my new wheels are

 

18 x 8.5 +30 Front and 18 x 9.5 +35 rear. These on an S15 fit perfectly.

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Yeah very useful thread.

 

Only issue is that ride height, tyre size and camber play a huge role in what offset you can run.

 

Eg. My car is pretty low with 215 45 tyres and has a bit of camber and Im running 17" X 9" with +5mm offset which is FAR lower offset than anyone else I see in your list and this is with stock rear guards on an s13.

 

Also to say that rims "fit perfectly" is a little subjective as it really depends where the owner wants the rims to sit. Generally the best fitment in Japan is considered as close to the guard as possible which usually means all sorts of guard modification and clearance headaches.

 

Anyway hope my post is of some value.

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great thread! :yes:

 

i'm going to be upgrading soon from my stock rims to some wide 18's so this info is very valuable.

 

just a couple of Q's:

 

what offset do stock 180 rims have???

 

also what would be a recommended offset for 18x8.5's on the front and 18x9.5's on the rear, on a 180sx and how much, if any guard work would need to be done??? will probably get pumped guards on the front and slightly flared rears anyway but am wondering if they would be needed or would the right offsets sort it out???

 

please keep the info coming!! :yes:

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I think the stock offset for the 15x6.5 rims are +40 ?

 

Yeah 17x8 +35 for me. Sits pretty flush with the front guard.

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any pics ppl have would be great also along with info like how wide, what offset and guard work if any that was needed :huh::yes:

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Can anyone tell me what the recommended offset would be for some 18x9.5's all round on an r32 gts-t so that the rim would sit pretty flush with the outside of the guard?

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unsure if this will help, however on my 180sx with irs

 

im running

 

front 17x8 +45 offset REQUIRES minimum of 5mm spacer (im using floaters)

 

rear 17x9 +45 REQUIRES minimum of 10mm spacer (im using 20mm bolton)

 

yeah, offset makes it difficult to fit these rims to 180sx.

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Has anyone got 18s to fit well on the rear of a 180? If so what mods/sizes were needed?

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streeter and specs15.....do u have pics of ur rims?

 

cos im thinkin of goin 17x9 +10 front and 17x10 +5 rear....

My car is running r33 gtr rims (+30 offset) with 25mm spacers, which brings the offset back to +5 and 215/45/17 tyres.

 

rearguard9st.jpg

 

I think some peoples idea of "flush" might be different to others.

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Heres a pic of mine with the 17x9 wheels in +10 offset. I'll take some over the weekend of my new wheels which I sit flush with the guards. Sitting flush for me is when the edge of the wheel is directly in line with the edge of the guard. I prefer to have 10mm spacers on however, but for the sake of being legal I keep them as is.

post-4-1108679951.jpg

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see....ive got Stage 21 20mm wide fenders for the front....so Specs15....wut offset would u recommend for 17x9 at the front?

 

im going 50mm for the rear so 17x10 +5 offset seems about right doesnt it? i dont mind the rims sticking out a little bit ;)

 

wuts ur take on it?

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just fitted some 17x8 & 17x9's on my s15 plus lowered king springs.

offset for 17x8 are +32 and 17x9 are +38 but guards had to be lipped. these flush against the guard.

i also found out that the perfect offset for 9inch rims on s15 is +47.

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7.5 inch wide, -5 offset :P

guard require flaring....

also ran -35 at 1 point, it was stupid....

require widebody :o

s13.

 

offseta.jpg

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S13 with 30 mm wide rear fenders, negitive camber, and stretched tires.

 

Stock width: __x9 +5 (9*25.4/2-5(Rim Offset)=109.3mm+30mm(wide fenders)=139.3mm(Total extra space available)

 

__x9.5 (9.5*25.4/2+19=139.65mm) __x9.5 -19mm

__x10 (10*25.4/2+12=139mm) __x10 -12mm

__x10.5 (10.5*25.4/2+6=139.35mm) __x10.5 -6mm

__x11 (11*25.4/2+0=139.7mm) __x11 +0mm!

__x11.5 (11.5*25.4/2-7=139.05mm) __x11.5 +7mm!

__x12 (12*25.4/2-13=139.4mm) __x12 +13mm!

__x12.5 (12.5*25.4/2-19=139.75mm) __12.5 +19mm!

__x13 (13*25.4/2-26=139.1mm) __x13 +26mm!

 

 

S13 with 50 mm wide rear fenders, negitive camber, and stretched tires.

 

Stock width: __x9 +5 (9*25.4/2-5(Rim Offset)=109.3mm+50mm(wide fenders)=159.3mm(Total extra space available)

 

__x9.5 (9.5*25.4/2+39=159.65mm) __x9.5 -39mm

__x10 (10*25.4/2+27=159mm) __x10 -32mm

__x10.5 (10.5*25.4/2+21=159.35mm) __x10.5 -26mm

__x11 (11*25.4/2+20=159.7mm) __x11 -20mm

__x11.5 (11.5*25.4/2+8=159.05mm) __x11.5 -13mm

__x12 (12*25.4/2+2=159.4mm) __x12 -7mm!

__x12.5 (12.5*25.4/2+1=159.75mm) __12.5 -1mm!

__x13 (13*25.4/2-6=159.1mm) __x13 +6mm!

 

Footnotes:

The above tables are a general guide not absolutes.

Higher or lower offsets can be run if needed modifications are done.

(!) Designates widths and offsets that are not recommend in conjunction with given wide fenders.

Offsets are not recommended do to clearance between the strut housing and the inside wheel.

Figures for “Stock width” were taken from a post "Streeter" made.

Edited by Rayne
  • Upvote 1

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Here's a tricky one, what offset would I need to run 18 x 7.5s on the front and 18 x 8.5s on the back of a 180sx with a 5 stud conv. lowered to 100mm off the floor. That is my dilemma. :wacko:

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Clearance of wheels for Z32 brake upgrade is entirely dependent on wheel spoke AND wheel design, NOT on offset of wheel.

-Wheel width/offset needed for clearance of coilovers is as follows (disregarding brake clearance):

 

* 6" +54 or lower

* 6.5" +45 or lower

* 7" +40 or lower

* 7.5" +34 or lower

* 8" +30 or lower

* 8.5" +24 or lower

* 9" +20 or lower

* Please note that this does not take into account variations in offset calculation by manufacturer, or tire sidewall bulge. This list also does not take into account differences in design of coilovers (esp. lower brackets on coilover kits which can cause changes in wheel clearance issues). This list also only applies to the FRONT WHEELS and is intended as a GUIDE for reference. Please note that this list does not apply for all coilovers and the offset needed to clear suspension will vary between wheels and also between different suspension types.

 

-The LARGEST wheels that will fit the front of a S13/14 with stock fenders is 9" wide. The rear can take up to 10.5" wide with a very specific offset AND must dial in negative camber. To fit large wheels one must use negative camber to ensure proper fender clearance.

 

 

The above information was copied and pasted from the 240sx Advanced forum on freshalloy.com

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Great idea.. I think it deserves to be a sticky.

 

BTW, my new wheels are

 

18 x 8.5 +30 Front and 18 x 9.5 +35 rear. These on an S15 fit perfectly.

u mean perfectly as in the wheel edge (looking at cross-section, i.e. the front of the car) is exactly in line with the STOCK wheel arch?

 

so that would mean:

 

17x9 +10 would have 20mm a bit out of the stock guard yes? (so 20mm replacement front fenders would fix the problem right?)

 

17x10 rear +5 offset would make it stick out 30mm from the stock guard right? (thus 30 mm rear overfenders would be ideal right?)

 

but if im going 50mm rear overfenders for my s15: to sit flush i would have to go -15 (NEGATIVE 15) offset

 

correct me if im wrong please. thanx!

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^^^ Use the offset calculator above.

 

Your front will actually be closer to 26mm further out due to the difference in wheel width.

Rear: 36mm further.

 

An offset of -9 on a 10" rim will give you a difference of 50mm.

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+10ish would make it flush

Is that for the front or the back? I won't be running coilovers. Also athid have you still got those parts available atm?

 

What is the offset of the stock 15s that come on the 180, so I can use the calculator.

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+10ish would make it flush

Is that for the front or the back? I won't be running coilovers. Also athid have you still got those parts available atm?

 

What is the offset of the stock 15s that come on the 180, so I can use the calculator.

 

15x6 +40 is stock offset if you still have the stock wheels you can look at "Inside" of the wheel and find out the height, width, and offset.

 

Look at the spokes and you will see something similar to "15x6JJ +40et" You will have to look closely for the information, sometimes the offset can be found on a different area than the height and width. Do not worry about the meaning of the "J's"or the "ET" The important information are the numbers and the plus or minus sign.

 

Another thing reread the posts here in this thread. Some of the information posted, already, can be very helpful.

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see....ive got Stage 21 20mm wide fenders for the front....so Specs15....wut offset would u recommend for 17x9 at the front?

 

im going 50mm for the rear so 17x10 +5 offset seems about right doesnt it? i dont mind the rims sticking out a little bit ;)

 

wuts ur take on it?

Based on SpecS15 wheel size and offset (17x9 +10)

 

For the fronts a negative 10 offset would be recommended.

For the rears a negative 27 offset would be recommended

 

If stock fenders are going to be used the "Backspace" of a rim needs to be known.

 

Formula to find how much backspace there is:

1.) Multiply "Stock" width by 25.4 to convert rim width into mm (9*25.4=228.6mm)

2.) Divide rim width by two for the centerline of the wheel (228.6mm/2=114.3mm)

3.) Subtract or add "Stock" offset for the amount of backspace. (114.3mm+10=124.3mm)

 

The backspace for SpecS15 wheels is 124.3mm

 

To find the correct offset for the new wheel:

Keep stock wheel backspace in mind when doing the calculations for the new wheel.

1.) Multiply width of new wheel by 25.4 to convert rim width into mm (10*25.4=254mm)

2.) Divide rim width by two for the centerline of the wheel (254mm/2=127mm)

3.) Subtract or add offset for the amount of backspace. (127mm-3mm=124mm)

 

If wide fenders are going to be used the outside width needs to be calculated.

 

To get the outside width do the following calculations:

 

1.) Multiply "Stock" outside width by 25.4 to convert rim width into mm (9*25.4=228.6mm)

2.) Divide rim width by two for the centerline of the wheel (228.6mm/2=114.3mm)

3.) Subtract or add "Stock" offset for the amount of outside width. (114.3mm-10mm=104.3mm)

4.) Take outside width and add the additional fender space.

20mm wide front fenders (104.3mm+20mm=124.3mm)

30mm wide rear fenders (104.3mm+30mm=134.3mm)

50mm wide rear fenders (104.3mm+50mm=154.3mm)

 

To find the correct offset for the new wheel:

Keep stock outside wheel width in mind when doing the calculations for the new wheel.

1.) Multiply width of new wheel by 25.4 to convert rim width into mm (10*25.4=254mm)

2.) Divide rim width by two for the centerline of the wheel (254mm/2=127mm)

3.) Subtract or add offset for the amount of backspace. (127mm+27mm=154mm)

If added offset will be negitive. If subtracted offset will be positive

 

Finally use the offset calculator to double check calculations.

(__x9 -10)

The clearance from stut housing to the inside of the wheel will be 20mm MORE

The outside edge of the wheel will EXTEND an extra 20mm

 

(__x10 -27)

The clearance from stut housing to the inside of the wheel will be 24mm MORE

The outside edge of the wheel will EXTEND an extra 50mm

 

Backspace is the amount of space on the inside of the wheel. (Mounting surface to the inside edge of rim)

Edited by Rayne
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^^^^ Didn't work for me.

Stock size - 15x6 +40

 

1. 6 *25.4 = 152.4

2. 152.4 /2 = 76.2

3. 76.2 - 40 = 36.2

 

No wide fenders.

 

New wheel - 18 x 8.5

1. 8.5 * 25.4 = 215.9

2. 215.9 /2 = 107.9

3. 107.9 - (71.7) = 36.2

 

How can you have a +72 offset rim ????

Am I doing it wrong or will this just mean the rim will have more backspacing than stock or what? Maybe with an extra 40mm backspacing it will reduce the offset to acceptable +32.

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