downhil

I've been looking for a new set of rims for the s2000, and in the process absorbing a lot of knowledge and taking a lot of notes about sizing and fitment. I'm a numbers guy by nature, and I like it when there are 'rules' about what works and doesn't.....but the offset and rim sizing seemed to always be this mysterious concept that some people understood and some people didn't want to even begin to.

These %'s are based on about 12 popular rim choices including very high offset wheels (OEM Honda, Volk, etc) and some lower options that some people said worked without any rubbing issues or fender rolling. As I get more and more info, the control group will grow and the %'s will become more accurate.

For the fronts I got an average of 28.4%. That means that the (positive) offset needs to be around 28.4% of the rim width. Most aftermarket rims were a bit lower than this...but the OEM rims have a 33.8% and 31.4% ratio for pre 04's and post 04's. So that brought up the avg.

EX. 18x8 +49 SSR SP1's 49mm offset/225mm rim width = .245 or 24.5%
17x7.5 +50 Volk's 50mm offset/187.5mm rim width = .267 or 26.7%

Rears came out a little lower at 28%.

EX. 18x9.5 +55 SSR SP1's 55mm offset/237.5mm rim width = .2315 or 23%
17x9 +63 Volk's 63mm offset/225mm rim width = .28 or 28%

I've been using this to help figure out if a rim is even in the ballpark of possibly fitting the s2000. The %'s are on the high side for offsets. So most aftermarket rims will fall a little under the 28.4 and 28. Anything over 24.5% for the fronts and 23.2% for the rear should fit fine.

Kel

This chart is helpful:
http://gs.tolan-hoechst.com/tirecalc.htm

As is this link:
https://www.s2ki.com/forums/index.php?showt...0&#entry3743412

rijowysock

its not about percetages

offset is a function of width

width *25.4 //2 +offset (in mm) =how the wheel sits.

i.e.

19x8+55 means that (19 does not matter at all, offset is a function of width)

8*25.4/2= 101.6mm on either side of "center line"

then +offset = 156.6mm From hub--> middle of car

51.6mm from Hub-->> fender lip.



if u crunch the "max" #'s listed below

ull see in the front.. the min mm from HUB-->> fender lip would be around 41.6mm (this would all depend on camber.. more camber=more mm u can fit..)
this will tell you if your "rubbing the fender lip"

but... too HIGH of an offset (and you will hit the inner wall

i.e.

19x8 +55 == 156.6 max mm (behind hub)


anywho. crunch the #'s below.. their are a few statisically unusual #'s but people have just guessed


ALL WHEELS no matter what the brand have the same "rubbage" (as long as width/offset=same
i.e. if you have 19x8 +35 on a volk/oem/maya/velox.. it wont matter if its too low on one brand its he SAME for all


as for the rear.. theirs more space and the wheels dont turn so u can obviously fit wider..

FRONT
7.0........................+40/+45.............................205/215/225
7.5........................+40/+55.............................205/215/225
8.0........................+40/+55.............................205/215/225

REAR ONLY**DIFFERENT HUB BORES FROM FRONT TO REAR***
8.0........................+45/+55.............................245/255
8.5........................+50/+65.............................245/255/265
9.0........................+55/+65.............................255/265
9.5........................+60/+65.............................255/265
10.0......................+73/+75.............................275/285


this should help if not PM me..


ur trying to say.. hey if this fits.. then. this might blah blah..

what it all comes down to is:

will it hit the fender lip? or will it hit inside the car?

THE MOST IMPORTANT THING. is tires tho..
a tire can make/break the rubbing.. dunlops run thin.. pirelli runs thick, nitto runs thin.. different brand run different ways..

so

1. look up and use that guide as a helper.. otherwise ur gonna sit there making guesses forever
2. reread #1
3. if #1/#2 are satisfied then.. look for a good tire.. too thick=rubs, too thin=hurt wheels
4. worst case scenario go w/ what other people have that works.


i make wheels for a living so.. my math is a lil more complex.. but no matter what #'s you come out with.. u must always look at the car. because their are toooo many variables to make up a formula.
contro arms/suspension/height/damper stiffness.. all affect if a tire rubs or not.. so for now just stick w/ what other people have and leave it up to people like me to broaden the spectrum of what fits(soon ill have 18x12's in the rear hopefully.. but this is because their 3 peice wheels and im custom making everything ON the car.. trial and error

im done for now

rijowysock

btw 95% of people that rub, its not because their wheels.. is because their suspension

on my civic^ i had some CRAZY offsets never heard of b4.. BUT.. i have tein flex w/ edfc and 10kg/mm and 14kg/mm springs w/ matching dampers.. and the "suspension travel" was around 5mm+/-

therefore no matter what the turn the wheel never moved more than 5mm.. so.. their was less variable to concern myself with when measuring..

pm me if you have questions its 10:29 and im tired and hopefully u get ther point

Wildncrazy

Add one more variable to the rubbing issue, ACTUAL tire width vs rated tire width.

Keep in mind the original SO2s were wider than their rated size and you get the idea. Almost everyone I have seen that didn't rub with lower offset fitments had tires that were rated LARGER than stock but were actually NARROWER.

I had 265 BFG KDs on the rear and they were almost 1/2" narrower than the stock SO2. Needless to say I had no rubbing, but I also had terminal oversteer.

NEVER GO BY RATED SIZE, always find out the REAL size.

I now have a pair of 18" BMW spec S02s for the front and a pair of Porsche spec tires for the rear. Both are considerably wider than their rated size. Now if only I could find a reasonably price rim with enough offset in the rear. 9.5" wide with 65 offset rubs like mad. It needs at least a 73 and a 76 would be better. BTW this is with a stock suspension and rolled fenders!

downhil

im an accountant for a 50 million dollar global company, so we won't go into math.

thats got to be the funniest thing i've ever read!


im not trying to make 'set in stone' formulas. i simply came up with a quick acid test (from averages) to see if a wheel is even worth my time exploring or not.

simply put...if a wheel has about 26% of its width in positive offset and is within the accepted 7-9.5" range for s2000's it will more than likely fit. i just thought i'd let other people know if they were still having trouble with deciding if a wheel will fit or not. just thought i'd help out and contribute.

downhil

the second link is very useful!

thanks!

rijowysock

it dont matter where you work.. or how much company is worth your math skills dont correlate to the fitment

u can make up formula's all day.. when push comes to shove use the #'s above.

you just made urself sound dumb.. send this to ANYONE who does wheels for a living and theyll laugh at you..

idk man. im done. have a good day at your 50million dollar company job.lol

i personally think its better to memorize that offset table then calculate %'ages...

like i said find out max mm between hub/fender lip and max between hub/ inside and thats ur #'s

w/e buddy.. i was just trying to help, seeing that I DO THIS FOR A LIVING. and i sell wheels to ferrari's and lambo's and porsches and each car is different.. so when i make a set i have to adapt to each car.

downhil

you fail to realize that i am not asking for advice. i am simply pointing out some basic ratios that i have found that apply to every wheel that fits the s2000 that i have run across.

i simply figured that there are other people out there that have the same thought process as me and would appreciate a quick calculation based on positive offset vs. width.

2 numbers vs.

FRONT
7.0........................+40/+45.............................205/215/225
7.5........................+40/+55.............................205/215/225
8.0........................+40/+55.............................205/215/225

REAR ONLY**DIFFERENT HUB BORES FROM FRONT TO REAR***
8.0........................+45/+55.............................245/255
8.5........................+50/+65.............................245/255/265
9.0........................+55/+65.............................255/265
9.5........................+60/+65.............................255/265
10.0......................+73/+75.............................275/285

i know which one i'll memorize.


if the thread doesn't agree with you, great, continue to use whatever method you prefer. the %'s are both based on wheels that are optimal for the s2000.

Wildncrazy

Downhill I don't know about the % issue, but I am local to you and I can show you that your ranges are wrong. I don't need math, I have video, scrapes on the inside of the wheel wells, etc., etc.

It all depends upon how skinny a tire you are willing to run. If you want to run a tire that is really as wide or wider than stock then your low offsets won't work.

As I mentioned before you have to check actual widths on the tires, you cannot go by carcass sizes which is all the rated size is (+-10%). When the tread is added you get very widely varying actual widths.

In other words a 255 isn't always 255 wide.