Square wheel setup- tire fitment

weebs25

Hey all..looking for some advice on my new setup. Ordered new wheels for my 370z. Ditching staggered 20s and going to a square 18x10.5 +25 setup. Going to need spacers in the back- 20mm?? Never had them before. 285/35/18 tires I’m thinking? I haven’t rolled my fenders or anything. Running Koni yellows and swift springs. Any help to verify I’m on the right track would be appreciated! I have read many posts on it all but I’m just not 100% right.

OptionZero

You are not on the right track. Cancel your order. In the future, research BEFORE buying ****.

Read this thread:
Wheel Fitment 101: START HERE

Track folks run 18x10.5 or 11 in the +15 to +20ish range and 275 to 315 width tires for more neutral handling

For all other purposes, primarily aesthetics, you're going to want something much more aggressive in the back

A stock nismo is 19x10.5 +23 rear and its sunken as hell

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weebs25

I have followed a ton of the track guys posts on here - and followed quite a few of them to what they are running or awfully close. Car isn’t a daily. Trying to get it prepped for auto x. Seemed like 22-25 was good for front with a 10.5? Going square I had the option with this wheel for +15,+25, so I figured 20mm spacer jn the rear, leave the front? Trying to avoid rubbing up front etc..

OptionZero

You will need adjustable front camber arms to run 18x10.5+25 with any sort of tire
And you aren’t doing any worthwhile performance driving without a front end alignment anyways

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AlWakRa

As OZ mentioned, camber arms are recommended, and I would say a must for lowered cars.

as far as specs, they are fine, you wouldn't have any issue with them, only front fenders if you don't have enough camber, I clear them with -2.9 camber but with 275/40/18 and +18 wheels.

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weebs25

Thanks for all the responses quickly. Just wanted to make sure I’m on the right track. Was going to try and push control arms off for a few
Months if possible but if I have to get them ordered I will get on it.Have so many priority parts I’m trying to get coming before I start auto x this year to prevent issues.’ Csc relocate, z1 diff kit, etc. I’ll order some 20 mm spacers for the rear this weekend too.

milmast

I have 285/35R18 RS4s on some 18x10.5+25 Enkei RS05RRs with SPL adjustable arms, with not a very aggressive alignment, with no rubbing at all. With stock arms, you will rub up front. I'm looking to change up my setup to run 315/30R18 square, but I'm still looking into it more.

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weebs25

Thanks for all the help! I found a killer deal on some 275/35/18 I’m probably going to order. I am still on stock control arms.planning to upgrade soon just have way to many parts coming already and want to get installed. Not even sure when my wheels will arrive I’ve been told it could be 8-9 months no idea.

milmast

If you're going to run 275s, I wouldn't suggest going with 10.5 wide wheels. They're going to have a bunch of stretch. I'd go with 9.5s or 10s max in that case. My old 285s RS4s had a bit of stretch on my 18x10.5s and I didn't love it. Just my $0.02 lol

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Z34 TS | R56 JCW | CS1 EX-L | FB6 Si
YouTube: milmast => http://goo.gl/1BsLa9
Instagram: milmast => http://goo.gl/8MWPBK

weebs25

I was still wanting a 285 or more- just concerned since I’m on stock control arms. Like I said I’m hoping to get new ones just ordered a diff and plenty of other stuff..just trying to get it all taken care of. Figured I’d get some more input! I don’t want to stretch the hell out of a tire.

OptionZero

what is the point of getting 285's in front and not getting adjustable arms?

The biggest weakness in the Z's handling is understeer and negative camber is part of the solution

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weebs25

No reason besides I don’t have the money right this second. I plan on getting some, but it might be a few months out, my damn wheels might be 8 so who knows.’just trying to get tires so I have them. I am trying to prep the car for reliability as well as performance and started at the most expensive parts. Wheels, wavetrac with all parts needed, I’m still on my stock csc at 60k! So I took the rest I had and ordered a cmak kit, and was planning to order the rjm clutch kit so i have an upgraded mc? I am about to order this tonight. I did the Konis and springs..rear camber arms.. don’t feel like having the car fail and create a ton more issues..figured if I i have to wait a bit and get them “just like I am on my front hotchkis bar and end links” I’ll survive. Dropped quite a bit at once

JARblue

You're strapped for cash and instead of buying the control arms you need for proper adjustment, you're going to spend that money on a "killer deal" for tires that don't fit your wheels? Did I get that right?

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weebs25

Not at all. I guess the entire point of my post was to get some advice from some who have more experience with a square setup since I have none. Simply trying to get what I have on my plate taken care of. All the parts INSTALLED. Had a friend send me a tire he was ordering last night that was available in the size I mentioned. He was pushing that it would work, I was hesitant. Have I explained myself enough? My car is in pieces since I had medical problems and couldn’t drive for a ******* year? Do you want me to keep going? Just trying to finish up and get prepared. I simply wanted some advice to help me out - what size, advantages / disadvantages. Shouldn’t be this difficult. Thanks to those who have answered my questions.

Brendan

20mm spacer out back and those wheels and tires wont need a fender roll. you will hit the fender tab before that happens. Tire size will be good too. just don't run too low. I was around 26.5" from ground to fender as nissan tells you to measure, running 275/40r18. now I am on 315/30r18 but I had to raise the car a little keep the 315 off the fender tab under heavy loads and bumps so its 26.75" now with the shorter but wider tires.

Heres the 315 with the car a little higher than I needed because I wanted to be sure they cleared. It was 27" in this photo _BES6507 by brendan sobers, on Flickr

and here is an older photo on the 275. I could get much lower since the tires were more narrow. same camber with both setups. -3.5~
_BES6734 by brendan sobers, on Flickr