mikez

Here this picture might help you understand it a bit more.



0mm offset = 1/2 of your rim's width, in the case of 8.5" (8.5x25.4x0.5) = 107.5 mm.

Your rim is 45mm offset, meaning you take 107.5mm - 45mm = 62.5mm of your rim sticks out pass your hub, and 152.5mm of your rim's width is behind the hub.

Now you say you have .7" from your sidewall to the edge of fender? 0.7" = 17.78mm. Meaning you will need to bump out your rim another 17.78mm to be flush.

A 15mm spacer would mean you move another 15mm beyond the hub, thus your overall offset would be 45mm - 15mm, 30mm offset on an 8.5" rim. Giving you (0.5)(8.5" * 25.4mm/inch) - 30 mm = 77.95 mm of your rim sticking out, exactly 15mm more than before the spacer.

So now you would be (0.7" * 25.4 mm/inch) - 15mm (spacer) = 2.78mm from rubbing (theoretically from your measurements.

You can follow my steps for the front as well.

Notice in my drawing I show how the camber curves the wheel in, so the angle of the wheel's slant gives you some more room to play with.

Also notice how I drew the tire kind of bulging, getting the offset right is only half the battle, a lot also depends on how fat or bulging your tires are.

Hope that helps, looks like my engineering courses came in handy after all

as3.0cl

iTrader: (2)

you can go pretty aggressive...as long as you keep the rolling diameter between the front and rear the same, for example.

i just picked up MRR HR-2's
19x8.5 +35
19X9.5+39

i was going to go +45 on the rear but after tlaking to adrian at B2 he said many people want spacers to push them out so i went a little more aggressive but i'm also going to be running a pretty thick tire out back.

the tires sizes i will be running are
235/35
275/30

this equated to a .1% difference in rolling diameter, virtually no difference, thus not messing up the differentials.

as3.0cl

iTrader: (2)

MikeZ -- what rims are you planning on sticking on your car out of curiosity, going to have to be real low offsets

mikez

I am thinking of Work Emotion XD9, 18x9 unsure about offset right now- up front, and 18x10 +38 in the rear, running 245/40 front and 275/35 rear

mdgrwl

iTrader: (7)

Thanks man. So from the math ect... it looks like I'll only be able to run 15mm spacers in the back? Will the camber help me out at all to go 20mm? Or based on my measurements you think I'm pushing it? You said I would be 2.78mm away from rubbing, almost 3mm. Will the camber give me an extra mm or two so I could fit the 20 in the rear?

llamaboiz

one thing... nothing is worse as rims with no drop in my book, but the second thing i hate most? ppl who buy rims then put spacers... im sorry but that is just ghetto... if your gonna spend the money on new rims, get it with the proper offsets so you dont have to run spacers

mikez

That is really hard to say, depends on how much you camber in and how accurate your measurement is from the actual geometry of the suspension right now.

I would say 15mm is the safe bet, 20mm could work, but you should save up some extra cash just in case for fender work. Sorry couldn't be more specific, this is where the offset game goes more into luck and guessing than math and science.

And ignore llamaboiz, not all people is as elite as them Hawaiian crew and their godly expectations

mdgrwl

iTrader: (7)

They make the wheels I'm planning on getting in a 30 offset which would be perfect for the rears then, no spacers needed... but they wouldn't work for the fronts.... too agressive right? So in order to have the option of rotating the tires all around the car, the choice is going 45 offset and working w/ the spacers from there.... anyway, this is still more then I can understand for some reason.... uh.

What would you do if you were in my situation I guess simplifies everything... being i'm an IDIOT!

mikez

19x8.5 +30mm up front will look good, but you might be rubbing during turns. Personally if I am looking to look good while being able to save money and rotate tires, I would go with the spacers.

There is absolutely nothing wrong with either choice man, I run spacers and I don't even rotate my tires so it means nothing to me

mdgrwl

iTrader: (7)

I'm thinking of just getting the 30's all around and taking it from there. The possible rubbing your speaking of... you talking rubbing one of the inside walls of the wheel well? (nothing a heat gun couldn't fix, correct?) Or are you saing the lip of the fender?

Also, if I go 30's all around and I see I have say 5mm more of room in the back, is adding universal 5mm spacers okay? Don't have to be vehical specific hub centric if its just a 5mm spacer right? Or am I once again an idiot? LoL...

mikez

+30 up front you will be fine, just gotta heat gun that bulge part in the wheel well. The F sport doesn't allow you to go low enough up front for any sort of fender issues. This dude runs 19x8.5" +22mm front, and you can look at what it looks on his car here:

https://www.clublexus.com/forums/3933320-post7.html

I think if you have 5mm in the back, you should just save yourself the money since it will look very good already, 5mm is 1/5", light years better than the stock's 1" haha. And I would never touch universal spacers, if its not hub centric, it is not suitable for driving. Don't risk it.

mdgrwl

iTrader: (7)

Thanks... yeah, I'll prolly be happy w/ just the 30's all around. Decision made, thankd Mike. I know I haggled you w/ many questions. Much apprecaited.

Ice350

iTrader: (1)

In this case the definition would be a wheel with the offset so that spacers would not be needed.
I am really lost on this one. I can't think of one logical reason to buy a wheel that doesn't give you what you want. There are similar looking wheels...there has to be. SO why do this?

mdgrwl

iTrader: (7)

If you can find a replica, or something even remotley close to the Five Axis S5:F wheels, please point them to me... I've searched and searched for days! The look of these wheels is so specific, and I love them so much, messing with offsets and spacers if need be is all worth it to me.

With that said... I don't need spacers. Me and Mike figured out (well Mike mainly) that going 30 offset all around will do it up just nice!

Ice350

iTrader: (1)

I haven't seen a 5 axis wheel that I liked but that doesn't really matter...it's what you like.
I kinda thought 30 offset would be okay......it's aggressive but not enough to keep from getting the wheels you love. It's probably gonna stick out a little but that's a small price to pay for your dream wheels.

PS
Just went online to view the five axis line-up. They are tuner styled wheels. Not my cup of tea but again, it's your thing...do what ya gotta do!