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Podiatrist
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Discussion Starter · #1 · (Edited)
So I decided to make a sort of "guideline" for wheel fitment with offset.

This is a guideline. If you decide to stretch or squeeze tires onto a rim, you'll change clearance.

This is a guideline based on calculations from my 8.5 rear with a 42 offset.

Someone correct me if I'm wrong.
What I based it on: If a wheel is 1 inch wider, you will be .5 closer to the fender. It will need to be corrected by "offset" which is 25.4mm per inch. So if your wheel is 1 inch wider, half an inch needs to be corrected for with 12.7mm offset.

The setups listed below assume a normal sized tire and is the furthest you should push the wheel out.

Front wheels (With a conservative drop)
(7)..... +32
(7.5)..... +39
(8)..... +45
(8.5)..... +51

Rear Wheels ( With a partially shaved fender)
(7.5)..... +30
(8)..... +37
(8.5)..... +42
(9)..... +48
(9.5)..... +53
(10)..... +61
 

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Podiatrist
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Discussion Starter · #2 ·
I would actually appreciate a double-check cause if I made any mistakes it could cost someone a pretty penny in a wheel purchase.
 

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thanks alot sophie

thanks alot sophie

this chart means alot ot me...planning on purchasing some wheels in the new future so...
 

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dammit sophie i bought rims from your chart it took 6 weeks to come from japan and they dont fit i want my $3000 back.

=P

jk.


i have 18x8 offset 40 in the front 225/45/18 and 18x9 offset 45 in the rear 245/45/18, dropped to about a 1.5 finger gap. i rub so i will be lifting her another quarter of an inch or so to see if that doesn't ease up. fenders are unmodified but that most likely will change.
 

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i run +42 in the front w/ a 8 and a +48 in the rear w/ 8.5
the front rubs a bit. the rear is fine (partially shaved fender)
conservative drop?
can we get a ricer finger gap estimate on that? :lol:
i got .5 finger gap (if that) all around, hence the rubbing.
good post, it needs to be sticky.
 

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Discussion Starter · #6 ·
DonCorleone said:
dammit sophie i bought rims from your chart it took 6 weeks to come from japan and they dont fit i want my $3000 back.

=P

jk.


i have 18x8 offset 40 in the front 225/45/18 and 18x9 offset 45 in the rear 245/45/18, dropped to about a 1.5 finger gap. i rub so i will be lifting her another quarter of an inch or so to see if that doesn't ease up. fenders are unmodified but that most likely will change.
Shave your rear fenders and you should be ok. It takes literally about 45 min.
 

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Discussion Starter · #7 ·
Lex_Dymndz said:
conservative drop?
can we get a ricer finger gap estimate on that? :lol:
If you can't finger the gap, then it def aint conservative.
 

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Discussion Starter · #9 ·
it's easy. find my tutorial bitches
 

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im hoping to fit Evo8 wheels (17x8 35mm offset) wrapped in 235 40 17 tires on my altezza, i intend on shaving the fenders.

25mm wider than the stock wheel

12.5mm farther out + the 7mm offset increase (think the stock offset is 42mm?) from the stock wheel brings the evo wheels 19.5mm or 0.78* farther out.

People slap 20mm spacers between the hubs and stock wheels to fit supra brakes so the evo wheels will clear.
 

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I'd witnessed 19x8.5 35+ offset all the way around with shaved rear fenders and minimal roll to the front fenders. It's flush to the car with conservative dropped.
 

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8.5 in the front requires a minimum of +45 ... anything higher (+46 +47 ...) will not work due to interference with the control arm ..

my volkd ce28n 17x8.5 +47 needed a 5mm spacer to clear the inside on the front (which would make it a +42)... at a conservative drop .. no fender modding is required .. but anything lower to a point to no wheel gap would require fender modding
 

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Discussion Starter · #14 ·
wat_it_IS said:
I'd witnessed 19x8.5 35+ offset all the way around with shaved rear fenders and minimal roll to the front fenders. It's flush to the car with conservative dropped.
No you didn't. That's absolutely off. Even when cambered as much as possible, an 8.5 with 35 offset will hit the fender at all times, lowered or not. You also cannot roll the front fender. It's already rolled.
 

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Discussion Starter · #15 ·
Sirnixalot said:
im hoping to fit Evo8 wheels (17x8 35mm offset) wrapped in 235 40 17 tires on my altezza, i intend on shaving the fenders.

25mm wider than the stock wheel

12.5mm farther out + the 7mm offset increase (think the stock offset is 42mm?) from the stock wheel brings the evo wheels 19.5mm or 0.78* farther out.

People slap 20mm spacers between the hubs and stock wheels to fit supra brakes so the evo wheels will clear.
Did you even look at the offsets up top?
You're half an inch off with an oversized tire.
your situation will not work. stock offset is also not 42. It's about 48.
 

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Front 18x7.5 45 offset 225-40/18
Rear 18x9 51 offset 255-35/18

Slight rubbing in the front where it hits the plastic lining cranked all the way to the left or right, 35's in the front would prolly fix that. Absolutely no rubbing in the back. A bit less then one finger gap all around for the drop. It was bolt on and drive, no fender mods.
 

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for there to be a true catch-all post about this, i believe that the recommended tire sizes per rim width should be included, that tire diameter should be calculated (or even a calculator or formula provided) to show deviation from stock speedometer, and there should be exact points when we know that spacers will be needed or fenders shaved. it definitely won't be easy to do. especially with all the combinations available for our cars.
dave

i found some calculators from my old stomping grounds. some things will be different, because they are Neon specific, but many of them we can use. but if we had a format similar to this, specific to our cars, and made it a sticky , a lot less questions would have to be asked. http://neons.org/tire/
 

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Discussion Starter · #19 ·
DMTaylor said:
for there to be a true catch-all post about this, i believe that the recommended tire sizes per rim width should be included, that tire diameter should be calculated (or even a calculator or formula provided) to show deviation from stock speedometer, and there should be exact points when we know that spacers will be needed or fenders shaved. it definitely won't be easy to do. especially with all the combinations available for our cars.
dave

i found some calculators from my old stomping grounds. some things will be different, because they are Neon specific, but many of them we can use. but if we had a format similar to this, specific to our cars, and made it a sticky , a lot less questions would have to be asked. http://neons.org/tire/
That's true...but there are a lot more factors involved in just tire size and overall size. You also need to take into account height and travel.

I think this is a good base because if you get a wheel that sticks out half an inch from the fender, regardless of your tire size you're not going to make it work. So these are conservative MAX offsets per wheel size.
 

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Discussion Starter · #20 ·
gotswap said:
Front 18x7.5 45 offset 225-40/18
Rear 18x9 51 offset 255-35/18

Slight rubbing in the front where it hits the plastic lining cranked all the way to the left or right, 35's in the front would prolly fix that. Absolutely no rubbing in the back. A bit less then one finger gap all around for the drop. It was bolt on and drive, no fender mods.
You can't just "switch" to a 35 series tire up front. A 40 series sidewall is just about .3 inches bigger than stock. A 35 series sidewall will be smaller by about .6 inches.
 
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