I've searched and read plenty of threads regarding fitment of 18x11s. I'd like to run the same wheel front and rear to allow for me to rotate the tires. I've never run a spacer on a track car, but I'm not opposed to the idea. My car has the following:

• ASM front fenders (25 mm I believe)
• ASM rear over fenders (also 25 mm, I think)
• Stock-ish camber for now but plan on running in the neighborhood of 2.75-3 deg when these wheels would go on the car

In the research I've done, here are a couple of conclusions I've come to:

• Front: 18x11 +~40mm with Downforce (similar width) is a reasonable target (https://www.s2ki.com/forums/wheels-t...tment-1118134/)
• Rear: 18x11 +~40mm and +~60mm has been done, which is ~7.75-8.5 backspacing has been done a few times. It seems 18x11 +~40mm with the ASM over fenders should work? (https://www.s2ki.com/forums/wheels-t.../#post24215750)

There are two wheels I'd like to consider with a 285 or 295 square tire setup:

• APEX SM-10 18x11 +44, 7.73" backspacing (https://www.apexraceparts.com/wheels...-10-wheel.html)
• APEX EC-7 18x11 +52, 8.05" backspacing (https://www.apexraceparts.com/18x11-...ang-wheel.html)
• Forgestar F14 18x11 +43, 7.69" backspacing (https://www.teambeefcakeracing.com/f...per-18x11.html)

I'm also open to other wheel suggestions. Any thoughts or feedback on this? The car is primarily a track car. Thanks in advance!

 

Your going to have issues running a square set up when you get into these width range wheels. The rear is no problem, with the right offset wheel you can run 11.5"/315's if you want. The front is where you are going to have issues with an 11" wide wheel - either on the outside or inside depending on what your willing to sacrifice, ie no brake ducting for track use and ok will rubbing inner control arm and inner fender over bumps, or rubbing/cracking outer fenders. I just don't see an effective useable "threading the needle" here with just +25 up front, which is only really about +5-10mm when you consider a rolled and pulled front fender will get you an honest additional 15-20mm over stock and 10"/255's are max being fitted while accommodating useable track duty (parking lots for photos don't count as they fit) so that's what you need to base fitment on as the baseline when adding aftermarket fiberglass fenders that crack when they get hit.

So that said, I'd be reluctant to go any wider then a 10/255 on asm front fenders which means your forced to run that in the rear to run square. Or in my view the better option is to maximize the rear fitment no matter what and tune the suspension around that with what ever you have fit up front. Your going to get more total lateral grip out of a 255/315 or 255/295 stagger then you will with a 255/255 square set up. There simply isn't many aftermarket front fenders wide enough to comfortably fit a 11"/285, not without sacrificing something. If you look at a lot of the hardcore guys running those widths or wider up front on track, the fenders usually look pretty fubar with additional custom work either based off a cut stock fender or some rendition of a mutilated CG or J's fender.

 

285 Square on 18x10.5 up front - stock fenders. Take notes and modify accordingly

https://www.s2ki.com/forums/s2000-ra...-notes-624164/

Junky - he has a GT wing on the car already. Let him run a square setup... your staggered setups will understeer and not allow him to rotate tires to even out wear.

Car that he's building for reference:
https://www.s2ki.com/forums/s2000-ra...ess2k-1199201/

 

Whats more important, total grip with a properly tuned suspension for the stagger, or being able to rotate tires? 3rd option, get some wider front fenders and run 10.5/285 or 11/295 all around.

One should be so blessed as to have an easy handling S that tends to push first through a corner at triple digit speeds rather then what my car does, which is still overseer. The truth is, its very difficult to balance the car to be absolutely neutral in every instance from slow speed corners where no aero is in play, to high speed corners where there is aero at play, and at every track is different. Again in my view, get as much rubber you can get under the car for max total grip as a base, then tune how that grip is managed front/rear bias on track with tuneable suspension ie sways and or aero if you have it) and of course your driving inputs, with the expectation that the car will still shine at different speeds. Where do you want it to shine?? What end do you want it to tend to swap first at what speed at 10/10ths of grip, and will the car be less tiring/easy for you to manage there at 10/10th to be consistently fast throughout your session? Also if its just one particular track your going to, cater some set up to what seems to work best for the fast guys at that track if there is a consensus. If you have to rotate tires then that's likely a compromise in some performance your willing to leave on the table (unless your going 315 all around) for the sake of tire life management.

 

I fit 18x11 up front using forgestar C5 with +52 offset. front fenders are the evasive ones. rears have the usual pull with no scrub 285/30 tires. camber is 3.5 all around. wheel range is about 270deg before it scrubs my 3" brake ducks. hope this helps.

 

We go back on forth on this all the time. He's running aero - you go square with aero because it's faster, not just for tire life management. All of the global time attack cars run square because it's faster. The guys who really want to win, buy new sets of tires every 2-3 events, show up with new tires every competitive event, and aren't really concerned with tire life management. I guarantee that if a staggered setup was faster, they would run it - they don't. The Evasive cars and RSG cars are all on square setups. The rules aren't limiting their setups either - like is the case with STR auto-x where they are limited by 9" wide tires (but they're also limited by not being able to run aftermarket aero).

Aero lets you setup for the ideal, which is to setup for oversteer at low speeds, and understeer at high speeds. At worst, a non-aero - staggered tire setup will understeer at low speed and oversteer at high speed. That is neither confidence inspiring nor fast.

You have your opinions and preferences, but they are just that - no lap times, data, or competitive comparisons to demonstrate superiority.

 

I agree with some of what you say, however your statement on square being faster is misleading, you cant just take a block statement like that and ignore everything I said. If the front fitment is limited on tire width like it is with the OP and many S2k's, then square may not be faster, period. The fastest unlimited guys you state are all in the 295-335 zone of tire widths squared so they have already maxed everything front to back, but its also false that they all run square anyway. Quick search debunks that. Aero and tuning for the tire is crucially important, and yet also relative to the track and power the car makes to be able to be faster dragging big aero or deciding not to.

 

https://dsportmag.com/the-cars/super...ekend-racecar/

evasive - 18x10 - 285 square

https://www.s2ki.com/forums/s2000-ga...build-1189266/

Evasive - 18x11 - 295 square

Both of those Evasive cars linked are super charged. I know that all of the RSG cars are square setups - for both the super charged and turbo setups.

Top Fuel Voltex S2000

https://dsportmag.com/the-cars/featu...c-contender/4/

765 WHP - running 18x11 - 295 square


Arvou S2000

Running 18x9.5 - 295 square (that's a surprising amount of pinch)

http://www.advan.com/japanese/galler...lery/0361.html

There are a few exceptions obviously - most notoriously, Thorne's Big Bad Wolf - but that car is on a whole different level and built to handle a turbo with anti-lag. Most s2ks are not built to that level where a staggered setup will out perform a non-staggered one.
Given that OP is looking at OTS cast wheels rather than custom make CCWs, i'm going to assume that he doesn't have Thorne's unlimited budget to build whatever the F*** he wants to build and likely has some budget constraints.

Under budget constraints, the Evasive builds are considered quite lavish, and still opt to go square versus staggered.

OPs goals will likely be realistically better served running square versus staggered. Again, the data, laptimes, and telemetry that people have gathered, supports that. This is a 20 year old platform - not much revolutionary development going on that people are unaware of.

I'm not ignoring it. I'm responding and showing you why you're mostly wrong...

Moving to a different chassis and to full racing - the 2018 Nissan GT-R NISMO GT3 run in the Blancpain series is running 18x13 on 330 square wheels & tires. It is also a mid-FR layout with rwd - like the s2k - via modification to the rule set.
link to spec sheet: https://www.nismo.co.jp/en/products/...18-spec_en.pdf

 

^lots of good discussion here - might I chime in? I think there's the 'theoretical' fastest, and 'real-world' fastest. The difference being, what the driver feels comfortable/able to maximize with their skill, preference and budget. As most of us here are amateurs with limited budgets, I think these are more limiting factors than debating the theoretical fastest.

 

18x11 on the front with only 30mm over fender will have some contact on the front arms or the fender. You will need to go 40mm on the front to be safe.
On the rear you will need a slight pull but 18x11 will work.

We are more expensive, but can shave a lbs off the wheels you are looking at and give you the exact offsets needed.