Widest tires at stock ride height and diameter

So what's the widest tires I can fit at stock ride height without rubbing? I would like to keep as close to stock diameter as possible so it doesn't mess up my speedo too much.

So without messing with speedo and odometer accuracy the widest you’d wanna go is a 215/40R17

That puts you at a tire that is about 4.8% taller than stock and is still relatively easy to find. Going any wider than that would require you to drop the aspect ratio to keep the overall height of the tire in the neighborhood but afaik no manufacturers make 17” tires with an aspect ratio of less than 40.


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I ran 215/45 with coils lowered about an inch and I only rubbed slightly on the liners, never on the fenders though. Stock ride height im thinking you could get away with 225/40 without rubbing, but thats just my intuition. Now I'm lowered about 2.5 inches, on 15s with 205/50 tires, stepping to 225 40 on my next set as I dont rub with this setup and I want to max out my tire size to get more meatyness!

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Im running 215/40/17s on 17x7.5 wheels. Factory suspension too. No rubbing.


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Just so you know, 225/40-17s do not exist, save for 00-40 tread wear, full slick, road race/autocross ONLY Hoosier A7s/R7s.

In fact, I could not even find ANY 225/40-15s (full race or otherwise) anywhere.

Yokohama used to make a 225/35-17 in their S.drive model, but they dropped that size for their Fleva V701 replacement of that tire.

Hey Lizard,

How were those 215/45R17's as far as taller gearing? Could you feel increased resistance from spinning a taller tire than stock? I'm thinking of running that size on stock ST springs, no drop. Did that size give you a little more rim rash and pothole protection? Lol, I know nothing will compare to your 15's in that regard...

Has anyone here run a 235/40/17 size on factory suspension and wheel size? Tires below are 24.4” diameter which may be just on the edge of occasional rubbing, just not sure.
https://m.tirerack.com/tires/Spec.jsp?tireMake=Falken&tireModel=Azenis+RT660&partnum=34WR7RT660
Looking at tires for my first season on the ST and even though the dailies are Indy 500s 205 width, the 2 events I ran on them this past year suggested the car is relatively under-tired in stock class. My old Autox tires were 245/40/17s, tried those on the ST and quickly found rubbing issues, mainly in the back if I recall on the liners. No width running issues I could find surprisingly. This tire diameter was 24.7, not much different than the one above. May be too close. Any ideas?

You’d probably need a wider rim than stock for that to fit optimally, and at that point you could play with offset to help mitigate rubbing provided fender clearance isn’t an issue (at stock ride height I doubt it would be)


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Unfortunately SCCA H Stock classing limits you to stock wheel with and + or - 1” rim diameter. Looks like 215s it is.

I swapped wheels/tires with my Focus SVT one time because I had never used sticky tires on the focus before. I put the Focus 215/45/17 tires on my '15 Fiesta and they RUBBED.

I have a set of 215/40 dunlop direzzas that I have ran on track and absolutely no rubbing.

My '15 Fiesta has stock suspension.

I have a set of 215/40-17 RS-RRs on 17x8, 42ET Pro Race 1.2s, and they have never ever rubbed once, under ANY scenarios whatsoever, on the factory suspension/ride height (albeit they are 0.3" narrower in tread width than the D2 Dunlops).

If you want wide tires, may I suggest 225/45R15?
Pros:
-wide tire
-bonus 0.25 inch lowering without compromising suspension geometry
-no rubbing, even with ~1 inch or more of lowering (I've tried Swift and am lowered even more on coils)
-smaller lighter wheels (I love the Team Dynamics Pro Race 1.2 in 15x8")
-cheaper tires

Cons:
-no big wheel on small car look
-have to buy wheels
-slightly less clearance
-your speedo says you'll be going 70 mph, but you'll only be going 68.5 mph (link to comparison page- you'll have to re-enter sizes)

This is my plan as soon as I wear out my current summer set of tires.

215/45R17 - Vehicle definitely notices the additional tire weight and sidewall but at the same time I'm not breaking traction every time I get on the accelerator. Tread hits if you bottom out the stock suspension. Only rubbed on turn-lock in one direction when the dealer screwed-up the alignment on an unnecessary "repair" that I told them not to do. (My fault for trying to use warranty instead of doing work myself.)

The only other 'con' is that if you do not lower the car with this setup, and retain the factory ride height, the wheel/fender gap is really noticeable as compared to taller setups, due to the shortness of it's overall diameter. (IF anyone cares about that at all.)

Lowered, even a little bit, and it looks GREAT (especially with the Pro Race 1.2s, and their slightly convex spokes).

I wonder how a 215/45/R16 OR the 225/50/R16 would fit, with the right rims at stock height?

A 225/50-16 would definitely rub at even factory ride height, since my 205/50-16 Neo Gens (which admittedly run MUCH wider than most other tires that size in BOTH section AND tread width) on 40ET 16x8 Dekagrams rub at certain steering angles/braking on a not lowered at all FiST.

Many on here have run 215/45-16s on Dekagrams with slight lowering (like Swift Spec R ride heights), and not rubbed, and they even look decent on a factory ride height car.

I guess it depends on the tire you're using and more precise measurements. 225/50/16 with the Kumho v730, 200tw tire is 24.9" tall so highly likely to rub would be my guess. Even the typically shorter in height Hankook rs-4s are 24.7" so good luck with that not rubbing. My understanding is 24.4 or 24.5 is already pushing it.

Also keep in mind 225/50s are really porky weight wise. Going from a 205/50/16 (21 lbs) to 225/50/16 (25 lbs) with the Z3, you gain 4 lbs of unsprung weight.

I think 225/45/16 (Z3) and 215/45/16 (RT660s) are the best size even though they are a bit pricier.
I have 225/45/16 Z3s on my 16x8 +38 rpf1 wheels and had no rubbing at all -2 front camber and very slight rubbing -3 front camber. My ride height is close to stock but my spring rates are stiffer Swift 8/6k

A local guy here says he runs 245/45R16s (R888s) with "barely any rub". Thats a 24.6" tall tire, speedo would be off slightly.

I'm like an inch lower than stock on 225/45/16 R888R's with 16x8 dekagrams and 5mm spacers to clear my BBK, and I've totally rubbed through my fender liner where it touches the fender, and I've bent my fender twice now lol. That's with 7k front and 5k rear springs as well, so much stiffer than oem.

I think it'd be better if I didn't have the 5mm spacer, but it is what it is. I think 215/45/16 is the perfect size on a fiesta with 16x8's