Ultimate wheel fitting guide

[j0nbubz]

Ahh... Just got word from my friend who's picking up the rims that the specs are actually:

18 X 8.5 --- +32 offset 235/40/18 front

18 X 9.5 -- +38 offset 265/35/18 rears

I think that's what most of you are suggesting.. joy!

 

[Nicely]

That's a better profile

I still hold that you will have problems if you every decide to lower the car, both front and rear. The fronts are exactly the same size and offset as mine and they hit the arches if I lower too far. The same size and offset are on the rear and, with the camber sorted, JUST clear my rolled arches.

 

[j0nbubz]

Bad news.. just tried to fit my new rims.. but problems!!

1) fronts are too wide and hit my hks hipermax coilovers. already have 5mm spacers, but tried one wheel with 2x 5mm spaces =10mm, and it still barely clears the coilover..

suggestions?

 

[ichi-go]

If it was stock suspension, it will clear fine. Some coilovers are harder to clear than others so it's trial and error really.

Get a wider spacer or with 10mm, with the wheels installed, drive around for a min. Then try to touch the inner tyres to see if they are hotter than the rest of the tyre surface. If it is, u need more spacer, if it's not, then u are fine.

 

[j0nbubz]

bummer..

is it stupid to put 2x 5mm slip ons on top of each other?

I don't think u can get 10mm bolt ons

 

[ichi-go]

Pretty sure u can get it in any size. U just have to look around. But spacers in general are dangerous. Make sure u get quality ones as cheap ones are usually not machine perfect and it's not flat

 

[j0nbubz]

wheres nicely when ya need him!!

He use to/has the same size rims I think.. =D

 

[Topper]

I've got 8j ET35's and needed 5mm spacer to clear the coilovers, and is very close now to sticking out past the arch.

Mine barely clear the coilovers, i can only just get a peice of paper between the tire and spring seat, but its not scrubbing , i would have thought a 8.5j ET32 would fit fine for the arch, but with 10mm spacers on will push you out and leave the rims sticking out?

 

[ichi-go]

Run more camber, problem solved

 

[A'PEXi]

fit the rim with the spacer and put your hand behind the wheel to check for clearance... depending on how big your hand/fingers are you should be able to feel if its hitting or if there is minimal clearance. otherwise, just jack it up and spin the wheel to see if it scrapes anything... your best bet would to be run a larger spacer, thinner tyres and more camber.

 

[Nicely]

I've already PMd j0nbubz about this, but I'll mention it in the thread. Anything more than 5mm spacers will require longer studs. Running more camber WILL sort arch clearance, however, it will also reduce tyre life. How so? I've seen so much negative camber on certain cars that only a third if the profile is actually touching the road! This means that, not only do you wear the tyre three times as quick, but you will probably get more grip running the standard wheels and tyres!

 

[j0nbubz]

thanks for all the posts guys - I'll be trying to fix the wheels tomorrow arvo!

Thanks esp to nicely for an extensive explanation + pictures!

As topper has said, 10mm spacers are too much and cause the wheel to stick out of the arch. I'm not a fan of toying with camber, but a slight adjustment might be of need..

We'll see how it goes when I raise the coils =)

Thanks again

 

[gunner93]

I've fitted a 9 inch width rims at the rear shod with 235/45-17 rubbers with stock springs. I can still see negative camber on the rears.

Sitting flush on unrolled arches...

I wonder if i lower my car by 1 inch will it rub the arches?

 

[ichi-go]

No cause the camber will tuck in the tyres and wheels. And I got the same wheel as u.

 

[j0nbubz]

WHEELS HAVE BEEN FITTED!

The car is still dumped and 3/4 out of the 4 wheels are PERFECT.

My front left tyre is still marginally hitting the coil strut even with 5mm spacer.

There is not much camber at all on all 4's, however my rears have been rolled.

 

[gunner93]

My front tyre missed the strut by a finger gap.

 

[j0nbubz]

My right side is missing the strut by about a finger gap

My left is still hitting (as i mentioned earlier)

Will try to fix it up when I get some time =>

My rolled rears have allowed me to keep the car relatively low and all 4 are just about inside my arches at this stage.. looks nice =)

 

[ichi-go]

Ok. I'm bored so I'm writing these to help some people understand more about wheel fitments.

Offsets! What are they?

So the higher the offset number will mean the wheel will go into the arches further (+30 to +50 for example)

The lower the offset number will mean the wheel will protrude out of the arches further (anything from +20 to -10, yes negative offsets! the dark side. Unfortunately there is no way in hell you can fit negative offsets to the stock guards unless you are running 50mm wider arches)

Offset will also affect how the wheel looks. Why does the wheels look so much nicer in the manufacturer's website? simple. It runs low offset. These ofcourse is affected by the wideness of the wheels to achieve what we call concave/taper look.

A good example:
Non taper look

Taper look

Now that you are clear with what offsets do to the wheels. There are many factors to take into consideration when fitting your new wheels. camber/toe/tyre widths all play a role to what fits and what does not fits.

 

[ichi-go]

Below are a few of good fitments to show everyone what you can actually fit to the stock guards since everyone is so afraid to run lower offsets on their rides. I made this mistake and is regretting now! However this post is only showing what fits flush(my term of flush is top rim is very near the guards and bottom rim is sticking alittle out) Hope everyone can learn from this post of what you can and cannot fit.

All the cars below are running at stock guards rolled unless specified.

I'm sure some of you have seen ben's (SpecS15) s15. imho his has the best fitting

Wheels spec:
F 9J x 18 Offset +22 -2.5camber Tyres:225/40/18
R 10J x 18 Offset +25 -1.0camber Tyres: 255/35/18

Wheels spec:
F 9J x 17 Offset +28 -3.0camber Tyres: 215/45/17
R 9J x 17 Offset +17 -2.0camber Tyres: 215/40/17

Wheels spec:
F 9J x 18 Offset +24 Tyres: 225/40/18
R 10J x 18 Offset +34 Tyres: 235/40/18

(The front protrudes abit, wider front arches will fix that but I still like it )

Wheels spec:
F 8J x 18 Offset +29 Tyres: 235/40/18
R 9J x 18 Offset +32 Tyres: 255/40/18

Wheels spec:
F 9J x 17 Offset +22
R 9.5J x 18 Offset +22

^^Not 100% sure but I reckon that's what it's running


Hope this helps all! Have a good one

 

[Nicely]

:thumbs:

The one major thing which you've not mentioned, as it will affect everything, is ride height. What fits one S15 at a certain ride height won't necessarily fit another at a different height. Lowering a car causes camber. This is particularly true on an S15. What this means is that the tops of the wheels are pushed inwards the more you lower. Whilst this is a good thing for fitting big wheels under arches, as they tuck under nicely, its a truly catastrophic thing in terms of grip. Why? The more you lower, the greater the camber. The greater the camber the less tyre you have touching the road. Not only does this reduce grip, it also causes uneven tyre wear. In some circumstances I've known of only a third of the tyre width at the rear actually touching the road. This means the tyres wear out three times quicker and that despite running 255s, the effective tyre surface is less than the standard 205s!!

What does this have to do with wheel sizes? Well, to sort out your negative camber, you need to spend quite a bit on additional alignment components and laser alignment. When you do this, the tops of your wheels will be pushed back out...straight into your wheel arches they may have been tucked inside. In one fell swoop, ride height has suddenly dictated the width of wheel you can run... Its for this reason that one person can quite happily run a certain width and offset of wheel, yet someone else running exactly the same wheel and offset struggles.

Another factor is that the greater the offset, the more the rim is moved in...towards your suspension. Move in too much and your wheels will start rubbing on suspension struts. Every make of strut is slightly different. So, you may get rubbing with a Tein coilover, but not with a HKS...

Run wheels that stick out past your arches in the UK and you risk a producer off the police and having to find another set of wheels before the car hits the road again....