Wheel and tire fitment question- 15x8, 225/50/15

[Bimmerman]

Hi all,

I've been waffling on whether to sell my 95 Leg L Wagon or not, but decided that the answer is to instead make it more fun to drive compared to my track/DD E30. So... to that end, I'm going to be putting an H&R RSS coilover system on the car, and want to fit good wide sticky rubber to take advantage of it. Car already has sways.

I am looking at a 15x8 Rota Slipstream, et40, to be wrapped by the 225/50/15 Hankook RS2 (or RS3 if that size ever appears) or the 225/50/15 Falken ZE912s. Would these wheels and tires fit my stock suspension? Would they clear with the lowered coilovers? The Rotas are available in 15x7, 7.5, and 8, with a 57.1 mm centerbore (is this even close to correct size?).

I am fine with rolling my fenders if I have to, but if I don't that would be much better. I could also bump up to 16s if the wheels don't work; nothing has been bought yet. 15s are cheaper though.

What say the tire and wheel experts of sl-i.net?

[dodik]

all those width would take the 225 tire 7, 7.5, 8 so i would look at the cheaper one, and if you are going to go with coilover i would look for maybe 42 or 45 offset. most importantly look in member rides for other memebers that run similar size tires overall width and circumference see what they have, also check tire calculator and + sized wheels that tirerack recommends for your specific car. then do some calculation ill try to start them for you your stock offset i presume is +53 going with 40 moves your rim 13 mm outside by going to 8 inch wide wheel you are increasing you rim width by about 40 mm, 20 inside 20 outside so your outside lip of the rim will be 33mm more out then what you have now and inside clearance will decrease by 7mm. then you throwing in 225 tire that is 30 mm wider than your stock 195s 225 tire is about 17mm wider than your wheel so that say 9mm on each side so now you overall decreased inside slearance by 16mm and moved your outer face of the tire about 42 mm to the outside. now the most important thing is to go to your car turn your wheels to full lock and see if this combo would rub on the fender liner. gl

[Huffer]

If you run a 15" wheel you will want tires with a stiff sidewall - otherwise all your suspension will be going into trying to control body roll caused by squishy rubber.

[Bimmerman]

If you run a 15" wheel you will want tires with a stiff sidewall - otherwise all your suspension will be going into trying to control body roll caused by squishy rubber.

Right, that's why I'm looking at the Hankook and Falken tires; they're supposed to be max performance summer (H RS2) and UHP All season (Falken ze912). If I could get away with running a 17x8 and a 235/40, I would, but is that remotely possible without massive fender...adjustment? Or would a 215/45/17 on a 17x7.5 or x7 fit just as well? The reason I'm wanting a 15x8 is to stretch the 225 as much as possible to give additional strength and support for the sidewall. That...and 225/50/15 is essentially identical to stock diameter.

@dodik- thanks for the help, that helps me visualize where the wheel will be. Now if only I wasn't 4 months and 3000 miles from my car!

[dodik]

225 is wider than 8 inshes. 1 inch is close to 26 mm which is 8x26=208mm <225mm tire to stretch youll have to go with 195 or wider wheels like 9, 9.5

[Bimmerman]

225 is wider than 8 inshes. 1 inch is close to 26 mm which is 8x26=208mm <225mm tire to stretch youll have to go with 195 or wider wheels like 9, 9.5

poor choice of words on my part. The 225 is measured on a 7.5 rim for the Hankooks, so an 8" rim fits them perfectly. I'm not going for the euro/vw stretch look, I'm wanting broad shouldered squared tires....most support for the sidewall for the most tire I can fit.

[Huffer]

Or would a 215/45/17 on a 17x7.5 or x7 fit just as well? The reason I'm wanting a 15x8 is to stretch the 225 as much as possible to give additional strength and support for the sidewall. That...and 225/50/15 is essentially identical to stock diameter.

For handling, I think a 17x7.5 is the max size on a BK/BG. Anything bigger than that and you're running out of room under stock fenders and really asking the car to plow into the turns with the heavier mass of a big wheel.

For what you're doing though, I think a 16x7 would be fine. There's a sweet set of Rally Sparco wheels on 5mileimport that would fit the bill easily. You could run a 225 or 215 on a 16x7 rim and with the coilovers you're planning you'd have room under there for sure.

[dodik]

than yeah 8 or 7.5 is fine. im running 245/45/18 right now on 7.5" and my tires are pretty "square" i guess but imo that the best look/reliablity to have in my case. i just looked over your original post and if you are going to add coilovers go with much higher offset like 48 or 50 if you can find them. coilovers give you a lot more room on the inside because spring isnt so wide and this way you wouldnt need to modify fenders us much.

[jey]

The ZE912 all-seasons are not nearly at the same performance level as the R-S2s...

[Bimmerman]

For handling, I think a 17x7.5 is the max size on a BK/BG. Anything bigger than that and you're running out of room under stock fenders and really asking the car to plow into the turns with the heavier mass of a big wheel.

For what you're doing though, I think a 16x7 would be fine. There's a sweet set of Rally Sparco wheels on 5mileimport that would fit the bill easily. You could run a 225 or 215 on a 16x7 rim and with the coilovers you're planning you'd have room under there for sure.

Hadn't thought of that, and thanks for the links! With my E30, the popular 16" tire sizes in sticky rubber frankly don't fit, so I'm used to ignoring 16s. If they'll fit with good rubber here, than I'll happily use them!

What tire aspect ratio should I be shooting for though with the 215/225? My understanding is that based on a stock 185/70/14 a 215/50 or 225/45/16 will be essentially identical. Is it all that bad to try running a 215/45 or 225/50? I can't find sticky rubber in other sizes without dropping down in performance, with a few 225/45 as exceptions.

Also, is the +50et of those Sparco 16x7s what I should shoot for? How would that change with x7.5 or x8? Those wheels are really nice...I may have to grab those.

One last thought...if I'm going for essentially the same width/aspect in 16s as in 15s (225/50/15 vs 225/50/16) is the added weight and cost actually worth it? I'd think that both would have the same amount of sidewall flex and squish.

I did some more tire data searching, and true enough, tirerack measures 225/50/16s on a 7" rim. Will any of these not fit due to different tread and section widths? These were the only ones with both tread/section data available on tire rack

Hankook RS2 215/45/16: rim range: 7-8" measured: 7" section width: 8.4" Tread: 7.6" Diameter: 23.6" (0.9% too small compared to 185/70/14, http://miata.net/garage/tirecalc)
Hankook RS2 225/50/16 6-8" 7" 9.1" 7.6" 24.9" (2.7% too big)
Hankook RS3 225/50/16 6-8" 7" 9.1" 8" 24.9" (2.7% big)
Yokohama AD08 225/50/16 6-8" 7" 9.2" 8.5" 24.8" (call it 2.5%)

What strikes me most is how the 215 and 225 RS2 have identical tread widths, so the extra 10mm is going to waste, and how absolutely huge the tread of the AD08 is compared to the other options, at barely any difference in section width. Would the Yok fit?


than yeah 8 or 7.5 is fine. im running 245/45/18 right now on 7.5" and my tires are pretty "square" i guess but imo that the best look/reliablity to have in my case. i just looked over your original post and if you are going to add coilovers go with much higher offset like 48 or 50 if you can find them. coilovers give you a lot more room on the inside because spring isnt so wide and this way you wouldnt need to modify fenders us much.

Cool, that puts my mind at ease. If I had enough power, I'd go for wider....I like the look of meaty tires. So et48-50ish is what I should shoot for on a 7-8" rim?


The ZE912 all-seasons are not nearly at the same performance level as the R-S2s...

Very true. I included it as a nod to being sensible, as this car is going to be very infrequently tracked or autocrossed. That said, it may, and I do like driving in a spirited fashion....and I have snow tires for when the need arises. I'm much more biased towards outright grip than all season suitability....but as far as all seasons go, those look the best for my needs. If there are others that are stickier, please let me know though!

Again, thanks all for the replies, you've all been very helpful!

[rougeben83]

The RS2's are notorious for having a soft sidewall (comparatively), an azenis rt615 is better in this regard but I think it weighs a couple of pounds more and isn't as hydroplane-resistant as some of the other tread patterns...

The AD08 is a good tire, but also look into the new favorite among autoxer's the dunlop direzza star specs:
http://www.tirerack.com/tires/Sizes.jsp ... +Star+Spec (http://www.tirerack.com/tires/Sizes.jsp?make=Dunlop&model=Direzza+Sport+Z1+Star+Spec)

Also, the replacement to the old autox gold standard, the bridgestone RE01R, the RE11:
http://www.tirerack.com/tires/Sizes.jsp ... enza+RE-11 (http://www.tirerack.com/tires/Sizes.jsp?make=Bridgestone&model=Potenza+RE-11)

Both tires cost less or the same as the advans, here's TR's comparo:
http://www.tirerack.com/tires/tests/tes ... p?ttid=118 (http://www.tirerack.com/tires/tests/testDisplay.jsp?ttid=118)

Don't compare an all-season to any of these tires (ie that ZE912), theyre simply in a different league in terms of performance, at the slight expense of handling snow, standing water, and sub-40F temps.

A 48 offset is pretty much standard for 7-8" width, use this to visualize how offset changes with width:
http://www.bigcustomwheels.com/info_specs.jsp

I would go to a 16" wheel, it's a good combination of decent sidewall stiffness, tire size availability and cost, and weight. With a 15" wheel there's a lot more tire sidewall that needs to be reinforced to make it stiff and even then it's still not going to have the turn-in response as a lower aspect tire.

[jey]

225/50 16 rubs on the fenders at stock suspension height, especially with those high performance summer tires that run big for the size. Lowered it might be worse - or if you have the springs stiff enough it may not happen...

[dodik]

my suggestion for now would be to install your coilovers first or what ever suspension you would like to go with then go to your car and see (guestimate) how much clearance you have because most people here run lowering spring and struts not coilovers i thruthfully can rember how much space i had behind the tire when i had coilovers on my old BD, but ther was plenty of room for wider wheels with heigher offset.

225/50/15 and 225/50/16 are two different sized tires the difference is huge. just to make sure you know this 225 is the width of the tire in mm, 50 is aspect ratio of 50% of 225 in this case which equals 112.5 mm, and 15 or 16 is in inches outer diameter of the rim. so if you want to go 16 then 225/45/16 would be the closest to your stock size


use this calc its a little better than miata one imo. try to find the size of the tire that is within 1% of your stock for your speedo to read properly
http://www.1010tires.com/TireSizeCalcul ... ion=submit (http://www.1010tires.com/TireSizeCalculator.asp?action=submit)

[Huffer]

I ran a 215/45/17 on 17x7, with a moderate 50mm drop on stock/oem type struts on my Impreza wagon, had no rub issues. Tires were Goodyear Eagle F1 GD-D3's, so very stiff sidewalls but great ride.

Right now I'm on 205/55/16 on a 16x6.5 with a similar drop (maybe a little more) on oem type struts. If I went any wider than 215/45 on a 17x7 I would rub for sure.

having a coilover will get you plenty more space under there because the strut housing/spring is far smaller. You should also lose some weight from the suspension change which could help negate the effect of running a 16x7 or 16x8 vs a 15x8 wheel.

[Bimmerman]

I ran a 215/45/17 on 17x7, with a moderate 50mm drop on stock/oem type struts on my Impreza wagon, had no rub issues. Tires were Goodyear Eagle F1 GD-D3's, so very stiff sidewalls but great ride.

Right now I'm on 205/55/16 on a 16x6.5 with a similar drop (maybe a little more) on oem type struts. If I went any wider than 215/45 on a 17x7 I would rub for sure.

having a coilover will get you plenty more space under there because the strut housing/spring is far smaller. You should also lose some weight from the suspension change which could help negate the effect of running a 16x7 or 16x8 vs a 15x8 wheel.

Yea, it looks like going to 17s opens up more options. To cram a 225/45/16, the only options for trackable rubber is the stupid soft Toyo R1R...which doesn't last all that long, or the old Hankook RS2. 215/45/17 is a pretty common size on the other hand, with the Kumho XS, AD08, Z1, RE11 all major players.

The best options look to be either 205/50/16, 215/50/16, 225/45/16, 205/45/17, 215/40/17, or 225/40/17. Data from Tire Rack, Vulcan Tire, and TreadZone (aka tireshoppe).

205/50/16
Dunlop Z1 Star Specs
Hankook RS2
Toyo R1R (essentially an R comp...dunno how suitable this tire is to DD use. Might be fun to find out though!)

215/50/16
no performance trackable tires in this category

225/45/16
BFGoodrich K/A TDW2 (not same category though)
Hankook RS2 (though not through tirerack...hmmmm)
Toyo R1R

205/45/17
Bridgestone RE11
Yokohama AD08

215/45/17
Falken Azenis RT615
Bridgestone RE11
Dunlop Z1 Star Spec
Hankook RS2
Kumho XS
Toyo R1r
Yokohama AD08

225/40/17
None

235/40/17
All of these options, very common tire. Shame it needs so much work to fit on a BK/BD. Is it possible with just a roll? If so.....

So it looks like 205/50/16, 225/45/16, and 215/45/17 are the best sizes to buy.....and 215/45/17 should work according to Huffer. 205/50/16 should fit if 205/55 does, but will a 225/45/16 fit even though it is the right diameter?

A 235/40/17 fits among the best in terms of overall diameter, but the only picture I've seen is on sybir's car....which is a bit of an extreme fitment. Is rolling/pulling/flaring the only way to fit such a large tire? Would messing with offsets do anything?

@dodik, jey-- thanks a lot for the input. 225/50/16 would be awesome due to tires available...but isn't to be. That tire size calculator is much better than the miata one as well! I am definitely going to buy and install the suspension first, as I get back to the States at the beginning of ski season, so ultra performance tires aren't really useful then.

Again, thanks for the input, all!

EDIT: argh I can't stop thinking of the possibilities. I've seen some other members' cars with 225/45/17 on 17x7 et55 or so. Is this possible without rolling/aggressive fender modification? I want lots of grip...without rubbing...haha.

[Huffer]

Honestly I think you'd be fine with a 215/50/16 or 225/40/17 with the coilover suspension. Get an ET48+ wheel and you should be fine.

You'll actually find that a grippier tire compound will do more for you than simply track width anyway.

[gryffinwings]

I don't know why everyone bags on the Falken 912s, which is a tire that seems to have multiple rubber compounds depending on size. I've been using it in the 225/55-17 size, which is a w-speed rated tire. I'll admit it's not the best size to use, but it's what I got at the time. Anyways it handles well for what it is, I get it up to operating temp all the time when I'm in the mountains, and it grips pretty good, I've barely begun to push the limits of this tire. Of course there are better tires out there, but the 912 isn't bad.

IIRC correctly some 912s have a harder compound, for some reason, I saw a guy with 912s on a honda and the rubber was actually felt harder than mine, and I found out his size was rated at H-speed.

[dodik]

Honestly I think you'd be fine with a 215/50/16 or 225/40/17 with the coilover suspension. Get an ET48+ wheel and you should be fine.

You'll actually find that a grippier tire compound will do more for you than simply track width anyway.


Roger is right for your car 225 width is the widest i would ever go truthfully 205 or 215 would be more than enough, my 245s tramline like mofo at low speeds and turn around radius is huge now at high speeds though it handles way better.

[rougeben83]

Would messing with offsets do anything?

@dodik, jey-- thanks a lot for the input. 225/50/16 would be awesome due to tires available...but isn't to be. That tire size calculator is much better than the miata one as well! I am definitely going to buy and install the suspension first, as I get back to the States at the beginning of ski season, so ultra performance tires aren't really useful then.

Again, thanks for the input, all!

EDIT: argh I can't stop thinking of the possibilities. I've seen some other members' cars with 225/45/17 on 17x7 et55 or so. Is this possible without rolling/aggressive fender modification? I want lots of grip...without rubbing...haha.

Of course offset will do something. It's how you can maximize the width of the tire you can stuff under you wheel arch! It physically determines where the wheel, and therefore where the tire will sit in between your suspension and your fender.

I suggest you look at the calculator site I gave you, it does wheel and offset comparisons as well as tire diameters. You can get a visual idea of how offset/width/tire size work together, because right now I have a feeling you're just throwing popular number combinations that people have mentioned in the past without really knowing the meaning behind them.

For example, with an et of 55 and coilovers you'll have a lot more room for tires to clear the fender you are moving the wheel inboard with that high of an offset (which is the factory offset). Most wheels are lower offset to move the wheel outboard, to clear stock suspension components. coilovers tend to be narrower diameter, and more importantly eliminate the big spring perch on the strut that is usually what rubs on a tire first in that area. With coilovers and the right offset you can fit a tire without having to roll fenders, whereas someone with a stock suspension cannot.

First off, figure out what type of tire you want. You started shopping between an extreme summer tire and an all-season for pete's sake - they're two completely different kinds of tire. Second, figure out what particular tire you want, or at least narrow it down to a small group of equally performing tires. Third, figure out what size wheel you want - cost, weight, design, width availability all come into play here. Third figure out the fitment available for your selected wheel and size - this means the width and the offset. Finally, figure out what size tire will fit on your car, using the particular whee and fitment that you selected. This may mean going back a few steps to reevaluate your choices.

In other words, narrow your focus on what you want to do with the car, and then do your homework. This does not mean taking a popularity contest on an internet forum. Do some actual legwork...or in this case fingerwork. We all have a ton of opinions that we can give you, but none of them are exactly right for you. Right now you are all over the place, 15 wheels, then all season/summer tires, then 16's, now 17" sizes are being thrown in. You'll just end up being more confused now than when you started...

BTW, you initially selected a rota slipstream that was mean to fit a Dodge neon/chevy cavalier/vw jetta. Off the top of my head, rota makes (or at least made, I'm not sure if the slipstream is still being produced, or its selection of sizes and offsets have been trimmed down) a 16x8 AND 16x7, et48, 56.1mm centerbore which IS specific for subaru's, they may have those specs in a 15" fitment.

[jey]

First off, figure out what type of tire you want.


+1. If performance is what's important to you, pick the tire first, then the wheel. That is what Autocrossers do. The flowchart pretty much goes like this:

1. Pick the tire.
2. For that tire, pick the size that works best for the car. If none available, Go Back to Step 1.
3. Now that you have your tire size/diameter, find the widest wheel you can for that size.


Makes sense because you can find yourself a nice 8" wide wheel setup but if the only tires available that will fit your car are a bunch of truck tires you aren't coming out ahead.

[Bimmerman]

First off, figure out what type of tire you want.


+1. If performance is what's important to you, pick the tire first, then the wheel. That is what Autocrossers do. The flowchart pretty much goes like this:

1. Pick the tire.
2. For that tire, pick the size that works best for the car. If none available, Go Back to Step 1.
3. Now that you have your tire size/diameter, find the widest wheel you can for that size.


Makes sense because you can find yourself a nice 8" wide wheel setup but if the only tires available that will fit your car are a bunch of truck tires you aren't coming out ahead.

I think I gave you all the wrong impression when I mentioned the Falken. I only mentioned them as they are the highest performing all seasons, not because I am looking to buy them. The tire category I'm looking in is indeed autocross/track rubber, and in that category, I'm not terribly concerned which tire as long as it fits nearly the same rolling diameter as stock.

This car isn't an autocross car by any means, I just want my DD to react like my autocross/track car. Since this car won't compete often the differences between the various brands are relatively irrelevant for me...I just want something sticky that will exploit my suspension to the fullest. That's why I've been looking at what tire sizes are likely to fit, and picking a brand based on that. If a 225/45/16 will fit, I will be super happy.

My biggest problem is that I am in Europe for a few months and my car is back home, so I have no way to check or measure stuff. That's why getting a yes/no verdict on certain tire sizes or offsets from guys who have done this before is so helpful to me, and why it seems like I'm asking a size popularity contest. I'm not, just looking for feedback on what will/wont fit at what offsets if possible (though it sounds like et48 is good for just about everything).

Thanks for all your help guys and gals, I do appreciate it. I'm definitely overthinking this a bit too much.

[Huffer]

I'm definitely overthinking this a bit too much.

Yeah, you are. :P :smt021 :smt031