Wheels and Tires Fit

I have a gen 3 coupe I am building and I am getting close to the point of a roller so I want to order the wheels and tires. I like the Hallibrands that FFR sales but they seem pretty expensive to me and I figured this was an area I could save a bit of money. I found some American Racing wheels that I think will fit but I wanted to check with everyone before I ordered them. I think I am going to go with 18 inch wheels as I have the 13in IRS brakes rotors in the back and think I may try to upgrade the rotors in the front and will need the room. Also, these will be for the street so I am going to go with a higher tread wear tire for longer life.

The wheels I found are shown below. They are American Racing Wheels with the below dimensions. I wee that most people were running a 1" to 1.25" spacer with the stock wheels that have an offset of a little over 20 so I thought that an offset of 0 sounded about perfect. Am I correct on that? They also have the wheels with a +12 offset. Would the 0 offset fit the front and rear with a 295/30/18 tire? I feel pretty good that it would work for the rear but I am not as sure about the front. It would be ideal in my mind if I could just have a square setup for the street so I could also rotate the wheels. If these wheels won't fit, can anyone give me guidance on what I should be looking for. Thanks.

Diameter - 18"
Width - 10"
Offset - +0
Centerbore - 72.6
Bolt Patttern - 5x4.5 5x114.3

Attachment 108236

Compare that with the FFR wheel specs:

Front Wheel Size (Diameter x width): 18"x 9"
Rear Wheel Size (Diameter x width): 18"x 11"
Front Wheel Backspace: 6.00" (24mm Offset)
Rear Wheel Backspace: 6.46" (12mm Offset)

Jeff

Couple of thoughts. 1- A 295 tire is way to narrow on the rear. Min is a 315 and you can fit 335. 2- I'd be looking for a 11-12 in wheel to run 335s. 3- Although I don't have a coupe, I have seen many threads mentioning running wheel spacers on the rear so, while I can't give you exact numbers, I agree that a wheel w/ less backspace could be a good idea.

Okay, it sounds like the fronts would be questionable with a 0 offset and I would be better off with the +12 offset 18x10 up front. With the wider wheel and 295/30/18 tire I hope everything will fit. On the Snap on build they ran a 295/30/18 up front but I don't know the offset of the wheels the used or how well they really fit. I am going to hold off on ordering until I can get a little more clarity there.

In the rear, it sounds like I may still need a small spacer with a 0 offset wheel and a 295/30/18 tire. The tire is an inch narrower then the common 315 others have run, so 1/2" of extra space inside and a half inch from the 0 offset relative to +12 of the FFR wheels. From reading others builds, it sounds like an inch to a little over an inch is needed for the FFR wheels, so I am going to be close I think.

Part of what factors in for me is tire choice. Not a lot of options in the 315/30/18 and 335/30/18 and they are all expensive. Plus, these wheels and tires are just for driving on the street and registration. Once my builds is registered and shaken down on the road, I plan to buy a dedicated set of wheels and r compound tires for the track. I could be wrong but I think that 295 is still a wide tire and will be plenty as long as I don't let my right foot get too heavy. I am more concerned with it looking silly and tucked too far into the wheel well.

I used the FFR 18 inch wheels on mine with 1.25 inch spacers on the back 265/35 front and 315/30 back tires, The fronts are tucked in a bit too far and I might add spacers in the future.
If i did it again I would go with 18X10 front and 18X12 back wheels - 1 inch wider on each and larger tires
David W

Another thought for you. BFG Rival-s are the hot setup in autocrossing on street tires in larger sizes. In 275 and under the RE-71r work well too. The BFGs are available in 275, 315 and 335x18. Now, maybe in the last several months, the Rival-s 1.5 is also available in these sizes. I am not sure what track events you are planning but these tires would do really well unless you are racing others on Hoosiers. I'd think about David W's experience and maybe you only need one set of wheels/tires. I hate to see you skimp on your street tires and end up w/ skinnies that are going to cost $2k or so anyway for wheels/tires. BTW, I haven't made the move yet but these are wheels I am looking at. The 18x10 and 18x12s.
http://www.team3wheels.com/lt_iii.html

I am back to thinking about buying these wheels. They are light weight, cheap, and I like the styling. I just wish they had a 12" wide option as well. Below is the current plan. I know the rear is narrower then I can fit, but I am not really finding anything in my budget that I like that would fit with a larger rear.

Front: 18x10 +12 offset with 265/35/18 Hankook Ventus R-S4
Rear: 18x10 0 offset with a 285/35/18 Hankook Ventus R-S4

There is about a half inch difference in offset in the front wheels from the FFR Hallibrands. I could add a small spacer up front if needed but I hope with the 265 tire everything will fit and I won't need the steering limiter I would with a bigger tire.

The rear has about an inch difference in offset from the rear FFR Hallibrands but most builders seem to be using 1 inch spacer so... I hope I am right on the direction the offset moves the wheel. The 285 tire vs. the 315 that seems to be the standard for the FFR wheel should also give me just over a half an inch of clearance on the inside.

Is my understanding of offsets correct or am I moving things the wrong direction? I think these should fit, just be narrower in the rear then a lot of builders use. Thanks.

Quote:

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Originally Posted by Tree

Front: 18x10 +12 offset with 265/35/18 Hankook Ventus R-S4
Rear: 18x10 0 offset with a 285/35/18 Hankook Ventus R-S4

There is about a half inch difference in offset in the front wheels from the FFR Hallibrands.

The rear has about an inch difference in offset from the rear FFR Hallibrands but most builders seem to be using 1 inch spacer so... I hope I am right on the direction the offset moves the wheel. The 285 tire vs. the 315 that seems to be the standard for the FFR wheel should also give me just over a half an inch of clearance on the inside

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Use this website calculator to help illustrate the offsets: https://www.willtheyfit.com/

I have a 2017 Mustang GT that I autocross heavily. Back when it was first released, nobody expected anything larger than a 10” wheel would fit. Then as time went on, guys started pushing that idea and found that with minimal effort an 11” wheel would fit up front. I now have multiple sets of 19x11” wheels for the car and have calculated backspacing/offset/diameter/tire stretch or bulge, and more to the nth degree, even when clearances are down to millimeter levels.

The higher the positive offset the further the hub mount surface is towards the face of the wheel. (Think LESS deep dish). Note: this is referenced to the centerline of the wheel’s width. So a +50 offset on an 11” wheel is not the same as a +50 offset on a 9” wheel, which is why you can’t simply change the width of your wheel and match the old offset expecting the same fitment.

Comparing the “recommended” FFR wheel specs to your desired wheel purchase, the new front wheel will put the extra inch of width (9” to 10”) on the outside. The inboard clearance will be changed by only 0.7mm....essentially nothing at all for your purposes. This should fit easily. Clearance to the suspension is really no concern, but look at clearance to the body to confirm it’s good there too. I expect it is, since guys run much much larger setups than this on the Coupe.

Now for the rear, your new wheels will be virtually unchanged at the face (outboard) side of the wheel (0.7mm less poke) when compared to the FFR 18x11’s. Your loss of 1” width (11” to 10”) will all occur on the inboard side, so yes your suspension clearance will increase. No issues in the rear whatsoever. In fact, you may want to use a spacer to push the wheel out an inch still, since from the outside they’re gonna look exactly like the recommended FFR wheels which guys like to add spacers to.

If you want to get REALLY deep into this stuff, I can certainly help. I’m building my Gen 3 Coupe-R right now and will be pushing the boundaries of what is possible with wheel and tire sizes eventually. Currently I’m just focusing on getting the build started. :)

Thanks for the info on how the will really fit. I was about to order these wheels and my wife talked me out of it and into ordering some 19" wheels in the width I want. So now I am thinking of going with the below specs.

Front: 19x10 +12 offset with a 285/30/19 tire
Rear: 19x12 +6 offset with a 325/30/19 tire

The front with a 10 in wheel will match the inside clearance of the standard FFR wheels. The extra 1 inch of space will all be to the outside and should close up the gap there. I think with a 285 tire, I will be okay considering the FF manual says a 315 can be fit up front.
The rear wheels minimum offset is +6 so that is what I will go with. That puts the wheel about a 7mm closer to the suspension strut and about 19mm father out to the body, which I think should be fine. I know I will be okay on the outside, I just don't know that I have the 7 mm inside plus the extra 5 mm from the 325 v 315 tire.

Planning to order the wheels tomorrow but I will have a 6-8 week wait. Anything I am still missing. I know I need lugnuts. Anyone know a good place to order cheap or lightweight lugnuts from?

Minimum +6 offset sounds like you chose Forgestar or similar company for your wheels?

I think you made the right choice to go with something wider than a 10” wheel in the rear. You should thank your wife. 19” wheels are also fitting to the look of the car, yet with modern performance benefits too. Tire selection is already good and getting better every year honestly as more and more new cars use larger wheel sizes.

The rear fitment you’ve already calculated and seen the diagram of from that website I linked. The front will be no problem at all, you’ll have plenty of room there. The rear is just what you described too: 6.7mm closer to the suspension and 18.7mm further poke out when compared to the “baseline” FFR wheel specs Jeff outlined above. I doubt there will be any interference problems with that small of change on the inboard side, unless FFRs spec was pretty tight to begin with. The outboard side is just fine, and in fact really nice because you don’t need the 1-1.5” spacer to push the wheel out. As a reminder, if you notice it’s a bit tight for inboard clearance with the 12” rear you can always use a 5mm, 7mm, 10mm, etc. spacer to bump it out that little extra and have just as much or more clearance to the suspension as the FFR wheel specs. The extra poke out will not hurt and would actually bring you even closer to that “Golden/ideal” look that most guys try to achieve with the 1”+ spacers.

Your wheel and tire choice has my full approval, from an engineering perspective. Which wheel style is it, if you don’t mind sharing? And also what tires are you looking at?

As for lug nuts, look up Gorilla. Specifically their spline drive stuff. The black coatings are hard as nails, and the lugs are one piece (no flaky chrome caps to fall off or corrode). I have several sets in various lengths and they’re all awesome. Special socket is needed, but it’s an off the shelf type so I keep one in the car and one in the toolbox at home. Not really meant for theft-prevention, but the average Joe doesn’t have a spline socket so it is a useful deterrent.

You nailed it. I was thinking of the Forgeline CF5V in super deep concave. I'm kind of a sucker for concave wheels. I'll make everyone wait to see what finish I picked though.

As for tires, I will probably end up with Michelin Pilot Sport 4s but that may change. Hankook Ventus V12 Evo2 tires area also available in those sizes and I have run the prior generation of them before and thought it was a great tire that was a big improvement over the Bridgestone Potenzas I had on before the Hankooks. I think the Pilot Sport 4s is better tire then the Ventus, but right now there is about a $500 difference in price and I am not sure there is that big a difference in the tire. I would like a more aggressive tire though and would prefer something like the Ventus R-S4 or the R-11 but they don't seem to be available in the sizes I am looking at right now.

I'll look into Gorilla for the lug nuts. I am pretty sure we need 1/2"-20. Light weight would be nice with it being rotational un-sprung weight, but I also don't want to pay out the nose for them so I guess we will see what is out there now.

I just ordered the wheels and they called to ask the center bore that I need. I don't know and I can't seem to find it. Anyone know the center bore needed off the top of their heads. Thanks.

I'm away from my kit right now, so I can't answer for the front. If you have the 2015+ Mustang IRS in the rear, it's the stock S550 hub size of 70.5mm. I can measure the front but it will be a day or so. A call to FFR tech might have a faster answer.

Also, in reply to your previous post... I too am a sucker for deep concave wheels. I have two sets of deep concave wheels on my Mustang and they're awesome.

Tires: the Michelin PS4S (Pilot Sport 4S) is one of the best tires in it's category right now. Really great performance both wet and dry, long lasting, good looking, come in desirable sizes, etc etc etc. Given the choice, I'd pick them every single time over the Ventus V12, however I have zero experience with the latest Hankooks. The prior generation of V12 Evo was a decent enough tire, and I expect the Evo2 to be improved, but they are still not in the same league as the Michelins. Of course there is the cost to consider, so if it's a "Worth-it" sacrifice to go with the Hankooks and pocket the extra $500, nobody will ever blame you for that!

FFR front hubs are 1/2"-20 yes, and if you have the 2015+ Mustang IRS in the rear, FFR asks you to press out those bigger 14mm studs and press in their supplied 1/2"-20 replacements, so the whole car will be the same. Personally, that's the exact opposite of what I intend to do. I've already pressed out the 1/2"-20 studs from the front hubs and will be pressing in M14x1.5 studs to match the rears. Bigger is better, and a good jump in clamp load on the mating surface due to the bigger fasteners.

DO NOT USE ALUMINUM LUG NUTS......! Gorilla lugs are forged steel, and plenty light. The weight savings is better found somewhere (anywhere) else. Besides, there's not much ground to gain here anyway. Your spun-forged wheels will already be lighter than most other as-cast wheels, so sit back and enjoy that much larger weight savings and use the steel Gorilla lug nuts and never have to worry about strength, stripped threads, galling due to dissimilar metals, etc. They come in all sorts of styles. Open end, closed end (many lengths), chrome, black, hex drive, spline drive, you name it. I change from street to race, and then back to street wheels more times in a month than most people do in a year. Gorilla lug nuts are more than up to the task.

Well... got the wheels in the mail recently but they came with the wrong finish. I guess since Factory Five was willing to reveal they were doing a bronze wheel for the 25 anniversary, I may as well reveal that I also ordered bronze wheels. However, I ordered a matte finish and they came in a gloss finish which was a bit too Fast and Furious for the car, so I have sent them back to be refinished. Should be two more weeks to get sorted. I think factory five is doing a Ducati bronze which look lighter then what my wheels should be. I am thinking that the darker matte bronze will look good on a dark blue pearl paint that I am planning. Time will tell I guess.

Did you get a chance to mount them to see how the sizing you selected fits?

Nope, when I saw they had the wrong finish, I stopped unpacking them since I knew I would need to ship them back. I think the size that I got should fit well but I will post a confirmation in about two weeks.

Tree,
"Nice to E-Meet you" I'm waiting for my Coupe 65R to come hopefully in May. I believe like you didn't get wheel or tires with my kit and have been grappling with what to put under there. Been chatting with Logan over the past months to see what he did but last update from him was he hasn't finalized. I also like the idea of the super or ultra-deep Forestar F14 or CF5v. If you have gotten what you have below ( Front: 19x10 +12 offset with a 285/30/19 tire Rear: 19x12 +6 offset with a 325/30/19 tire) to work would you be willing to share your success/info and exact specs on what you purchased? Maybe even some pics of the wheel on the car?



PMTree
Thanks for the info on how the will really fit. I was about to order these wheels and my wife talked me out of it and into ordering some 19" wheels in the width I want. So now I am thinking of going with the below specs.

Front: 19x10 +12 offset with a 285/30/19 tire
Rear: 19x12 +6 offset with a 325/30/19 tire

The front with a 10 in wheel will match the inside clearance of the standard FFR wheels. The extra 1 inch of space will all be to the outside and should close up the gap there. I think with a 285 tire, I will be okay considering the FF manual says a 315 can be fit up front.
The rear wheels minimum offset is +6 so that is what I will go with. That puts the wheel about a 7mm closer to the suspension strut and about 19mm father out to the body, which I think should be fine. I know I will be okay on the outside, I just don't know that I have the 7 mm inside plus the extra 5 mm from the 325 v 315 tire.

Planning to order the wheels tomorrow but I will have a 6-8 week wait. Anything I am still missing. I know I need lugnuts. Anyone know a good place to order cheap or lightweight lugnuts from?

Quote:

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Originally Posted by only1moreracecaripromiss

Been chatting with Logan over the past months to see what he did but last update from him was he hasn't finalized.

Anything I am still missing. I know I need lugnuts. Anyone know a good place to order cheap or lightweight lugnuts from?

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Unfortunately, I STILL haven't ordered wheels, although I basically know what I want (pending confirmation from body measurements). The only remaining question is 18" vs 19". It comes down to tires, and certain sanctions limit tire size so need to decide where to run then build per the rulebook.

As for lugnuts.....GORILLA. Forged, one piece construction. Small OD so they fit the tight pockets on aftermarket wheels. Hardened so they hold up to thousands of cycles. No metal caps on them to hold water and rust from the inside out (like Chrysler/Dodge lugnuts that are renowned as the worst in the industry). I prefer the splined lugnuts, which double as a low level of anti-theft protection since they require a spline socket (standard 6-spline available anywhere BTW, not an individualized key-socket like the actual locking lugnuts you may be familiar with). They also offer standard hex drive if you prefer that.

Lugnuts aren't that expensive anyway, so I don't recommend searching for the cheapest option. Gorilla lugnuts from $40 to $80 per set will be a treat to work with every time you have the wheels on and off. Which if you're like me, is about half a dozen times per month.

PS. Hope I didn't step on Tree's toes, this being his thread. I'm eager to see the bronze wheel unveiling, and welcome his insight on these technicalities too!