What do you guys think of these SSRs
- Thread starter RelliMS3
- Start date
The width of the tire is pretty much going to be greater than the width of the wheel. If the wheel is 1/8" from the strut now a tire on that rim is likely to touch. A 235 tire should be about 9.25 in wide.
fourthmeal
Banned
Break it down to me a bit more, because I'm trying to figure out just how wide we can go. I've heard several times a 235/40-18 will fit if the offset is just right. I think it is a 50mm offset or better to work properly.
The advantages of going to this size of tire are major, though. So if it can be done, then DO it, IMO. Swampass runs this size, though he rubs ever so slightly on the rear...I think he has 48mm offset 18x8 O.Z.'s.
The advantages of going to this size of tire are major, though. So if it can be done, then DO it, IMO. Swampass runs this size, though he rubs ever so slightly on the rear...I think he has 48mm offset 18x8 O.Z.'s.
- :
- 2007 MS3
The "Team Cobb" vehicle uses 18x8 48 offset rims with 225/40 tires. The car is lowered to the same amount that most of us will lower our cars. I have to think that these guys know what they are doing. If the extra size from 235s was worth the fitment headaches, they would have used them.
If you go wider than stock, you need to drop the aspect ratio or the speedometer accuracy goes out the window. 225/40 reads slightly high on a car that came with 215/45 tires. Like the speedo reads 60 and you are doing 58 or something like that. Personally, I would rather be going a tiny bit slower than I think instead of a little faster. We all tempt fate with regards to speeding tickets too much anyways. It would suck big time to get a ticket from some cop who is pissed off for working a Sunday when you thought you were at the limit and in fact were a couple mph over because you had 225/45 instead of 225/40.
If you go wider than stock, you need to drop the aspect ratio or the speedometer accuracy goes out the window. 225/40 reads slightly high on a car that came with 215/45 tires. Like the speedo reads 60 and you are doing 58 or something like that. Personally, I would rather be going a tiny bit slower than I think instead of a little faster. We all tempt fate with regards to speeding tickets too much anyways. It would suck big time to get a ticket from some cop who is pissed off for working a Sunday when you thought you were at the limit and in fact were a couple mph over because you had 225/45 instead of 225/40.
fourthmeal
Banned
What really sucks is that because your Speedo is off, your ODO is off too.
Trust me, I know tire sizes (it was my profession to sell wheels and tires for years), but I was alluding to the exact nature of this car.
It seems that with the RX-8 wheels (which have an offset that is slightly more then 50mm), you can fit 235/40-18 tires in this car.
Just because Cobb was unable to do it doesn't mean you can't do it. Maybe they didn't want to use a different wheel then the ones they chose, who knows?! FYI DG Motorsports made their show car with some sort of 8-8.5" wheel and put 245/40-18's on it. How they did it, I'm very curious!
Trust me, I know tire sizes (it was my profession to sell wheels and tires for years), but I was alluding to the exact nature of this car.
It seems that with the RX-8 wheels (which have an offset that is slightly more then 50mm), you can fit 235/40-18 tires in this car.
Just because Cobb was unable to do it doesn't mean you can't do it. Maybe they didn't want to use a different wheel then the ones they chose, who knows?! FYI DG Motorsports made their show car with some sort of 8-8.5" wheel and put 245/40-18's on it. How they did it, I'm very curious!
I was talking about that one guy's 8.5" rims. I'd say if the RIM is 1/8 from the strut it's pretty likely a TIRE will rub on it.
I'm also using 235 tires (235/45 17s (8" width rims, 45 mm offset)). Here's a pic of my right-rear tire (all the tires look the same). These tires have been on my car for more than a month I think. I personally don't think I'm rubbing much if at all.
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Here's the front right (the file is too large for this site so you'll have to click the link to view it...). As I understand it rubbing isn't as much of an issue on the front.
Da Pic
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I'm also using 235 tires (235/45 17s (8" width rims, 45 mm offset)). Here's a pic of my right-rear tire (all the tires look the same). These tires have been on my car for more than a month I think. I personally don't think I'm rubbing much if at all.
[edit]
Here's the front right (the file is too large for this site so you'll have to click the link to view it...). As I understand it rubbing isn't as much of an issue on the front.
Da Pic
[/edit]
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Here are some pics to clarify things. 18x8.5 53mm offset 235/40/18
I should have fone with 245. I Played it safe with 235; I knew things would be tight. any body manage to fit anything wider than a 8.5 wheel on there speed.
"The width of the tire is pretty much going to be greater than the width of the wheel.
If the wheel is 1/8" from the strut now a tire on that rim is likely to touch. A 235 tire should be about 9.25 in wide"
The pics show how this is not the case
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fourthmeal
Banned
Wow that is a tight, TIGHT fit. Kudos on the very tough clearances! I'm curious to see how much rubbing if any is created if the rear suspension compresses fully.
FYI, I think a lot of people are out of touch with what the tire's size really means, and how its measured, as well as how a wheel is measured.
First, a tire's width is measured as configured on a rim width (that is explained in the specifications of the tire itself)
Second, the wheel is measured from the inside bead of the wheel (where the tire fits in), so the outside bead visible from those pictures is probably another 1/4" or so out from the 8.5" rim per side.
All that said, as you can see our clearances are CLOSE, and we must be careful with our offsets and widths. Could you imagine the trouble you'd be in if you used wheel weights on that inside lip? WOW!
FYI, I think a lot of people are out of touch with what the tire's size really means, and how its measured, as well as how a wheel is measured.
First, a tire's width is measured as configured on a rim width (that is explained in the specifications of the tire itself)
Second, the wheel is measured from the inside bead of the wheel (where the tire fits in), so the outside bead visible from those pictures is probably another 1/4" or so out from the 8.5" rim per side.
All that said, as you can see our clearances are CLOSE, and we must be careful with our offsets and widths. Could you imagine the trouble you'd be in if you used wheel weights on that inside lip? WOW!
- :
- 2007 MS3
Which is another reason to err the way I said: your mileage will read low!
My point of Cobb's setup wasn't that they couldn't do it but that they didn't bother. What they did wheel/tire wise was to get lighter rims. They increased the rim width about 12mm, and the tire 10mm. This was good enough for their road racing track car. If they figured the gains from going even wider were so negligible as to not bother, it is certainly food for thought.
One other thing to consider is that Mazdas (especially the front drive varieties) have a reputation for responding very well to reducing wheel/tire weight. There must come a point where the weight gain from the increased sizes causes losses in performance and suspension response that more than negate any slight skidpad improvement.
Good lord that's close! Those wheels look awesome too by the way. (2thumbs)Here are some pics to clarify things. 18x8.5 53mm offset 235/40/18
I should have fone with 245. I Played it safe with 235; I knew things would be tight. any body manage to fit anything wider than a 8.5 wheel on there speed.
"The width of the tire is pretty much going to be greater than the width of the wheel.
If the wheel is 1/8" from the strut now a tire on that rim is likely to touch. A 235 tire should be about 9.25 in wide"
The pics show how this is not the case
I stand corrected about the width of the tire compared to the rim. I'm glad I used the modifier "pretty much", there will always be exceptions.
Man... looking at those wheels again... I'm very jealous!
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fourthmeal
Banned
Which is another reason to err the way I said: your mileage will read low!
Sorry but your mileage will read high. The car will depreciate ever so slightly faster.
fourthmeal
Banned
Agreed completely on the lightweight wheel issue, and agreed on the fact that a heavier wheel negating any width advantage. BUT, if you can get wide and get light (like those beautiful Wedsport wheels), then you get the best of both worlds.
We need this type of solution, especially when adding power and increasing the handling potential of this car. It has a long way to go with sticky, wide wheel and tire assemblies.
We need this type of solution, especially when adding power and increasing the handling potential of this car. It has a long way to go with sticky, wide wheel and tire assemblies.
.[/QUOTE]I need to decide what to do now. Maybe an sts and cai, or maybe powdercoating. OR all three, probably still cheaper than new wheels and tires.[/QUOTE]
Tires are the biggest bang for buck change to any car. Problem is that our rims are not wide enough to fit the most benificial sizes. if they were 8 from the factory 235 sticky tires would do the trick and leave money left over for the other mods. keep looking for just the right wheels.
FYI: when using tire rack i found that if you look under other cars (eg.rx 8) you may be able to find wheels that will fit your speed but are not listed for it. Just make sure offset and bolt pattern are proper. They air on the side of caution on widths. The last thing they want are people coming to them with rubbing issues or other problems. my wheels were not listed for the speed, I found them under the rx8 listing.
Thanks man, stock there is no rubbing while driving in a spirited manner.(drive2)
When i put my coilovers on in the spring I will find out if a fender roll is in order. It looks like it will be close, the front should be fine. (yes)another good reason to use stick on weights.
.[/QUOTE]My point of Cobb's setup wasn't that they couldn't do it but that they didn't bother. What they did wheel/tire wise was to get lighter rims. They increased the rim width about 12mm, and the tire 10mm. This was good enough for their road racing track car. If they figured the gains from going even wider were so negligible as to not bother, it is certainly food for thought.
One other thing to consider is that Mazdas (especially the front drive varieties) have a reputation for responding very well to reducing wheel/tire weight. There must come a point where the weight gain from the increased sizes causes losses in performance and suspension response that more than negate any slight skidpad improvement.[/QUOTE]
Cobb tuning obviously knows there stuff. They think out there products and cars. They pay attention to details a lot of other companys overlook. However they developed thier test mule to run their suspension kit. That wheel size and there kit would be an excelent combination. I think with coilovers and a much higher spring rate a wider wheel has benifits. heck i would of gone 9 if it would fit.
Wheel weight is a huge factor, believe me that had a huge influence on my choice. The wheels and tires I chose are still lighter than the stock setup even at 8.5. I beleive its is the rwd miata that has this tendancy. It is very sensitive to unsprung wieght. It is also much lighter and therefore need less rubber brakes etc.
Thanks dude. just wait till the ride height is right. (nana)(2thumbs)
Tires are the biggest bang for buck change to any car. Problem is that our rims are not wide enough to fit the most benificial sizes. if they were 8 from the factory 235 sticky tires would do the trick and leave money left over for the other mods. keep looking for just the right wheels.
FYI: when using tire rack i found that if you look under other cars (eg.rx 8) you may be able to find wheels that will fit your speed but are not listed for it. Just make sure offset and bolt pattern are proper. They air on the side of caution on widths. The last thing they want are people coming to them with rubbing issues or other problems. my wheels were not listed for the speed, I found them under the rx8 listing. Thanks man, stock there is no rubbing while driving in a spirited manner.(drive2)
When i put my coilovers on in the spring I will find out if a fender roll is in order. It looks like it will be close, the front should be fine. (yes)another good reason to use stick on weights.
.[/QUOTE]My point of Cobb's setup wasn't that they couldn't do it but that they didn't bother. What they did wheel/tire wise was to get lighter rims. They increased the rim width about 12mm, and the tire 10mm. This was good enough for their road racing track car. If they figured the gains from going even wider were so negligible as to not bother, it is certainly food for thought.
One other thing to consider is that Mazdas (especially the front drive varieties) have a reputation for responding very well to reducing wheel/tire weight. There must come a point where the weight gain from the increased sizes causes losses in performance and suspension response that more than negate any slight skidpad improvement.[/QUOTE]
Cobb tuning obviously knows there stuff. They think out there products and cars. They pay attention to details a lot of other companys overlook. However they developed thier test mule to run their suspension kit. That wheel size and there kit would be an excelent combination. I think with coilovers and a much higher spring rate a wider wheel has benifits. heck i would of gone 9 if it would fit.
Wheel weight is a huge factor, believe me that had a huge influence on my choice. The wheels and tires I chose are still lighter than the stock setup even at 8.5. I beleive its is the rwd miata that has this tendancy. It is very sensitive to unsprung wieght. It is also much lighter and therefore need less rubber brakes etc.
Thanks dude. just wait till the ride height is right. (nana)(2thumbs)
- :
- 2007 MS3
You're right. Lost my head for a second there and didn't think about it long enough.
My major issue with the wide but light rims is that not all of us are made of money. I drive this car because it was a bargain price (IMO) for the performance you get. If I could afford a couple grand for rims I wouldn't be driving this car. It is a blast to drive, but let's face it, the pure front wheel drive setup is limiting on how much performance we can ultimately expect to get. All wheel or rear wheel both have more potential.
Has anybody seen a lightweight 18x8 with 48 or so offset in a simple, clean black design that isn't absurdly expensive? I plan on being conservative when/if I upgrade the rims and go with something like the Cobb setup. I think increasing the rim width in relation to the tire width will only improve handling response even more, so I would like to accomplish that if possible.
EDIT: Fourthmeal, that is an interesting calculator. It tells you if the rim you are selecting is too wide for the tire, but not if it is too narrow. After using it, I have changed my mind. I am now thinking in terms of 18x8.5 with 225/40. This will provide a nice wide platform for mounting the tire which should yield very responsive, firm handling.
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Good luck with your search for 18x8 with a simple clean design and not very expensive. There are only like 5 options for all black rims, nothing that looks that great.
- :
- 2007 MS3
It appears that the real clearance problems are not the rims, but the tires. With the correct offset, an 8.5 inch rim should clear nicely. Since I'm not thinking in terms of going that much wider on the tires themselves, I doubt they will be an issue. Until I saw that calculator, I didn't realize that 8.5 was considered a recommended rim width for a 225 tire (assuming the calculator is correct). When I do the math, an 8.5 inch rim comes out to 216 mm, which I hope would provide a very crisp, responsive wheel/tire combo with a 225 mm tire.
Fourthmeal, is there any rule of thumb for optimum rim/tire width ratio?
The factory 7.5/215 works out to 88% rim/tire ratio, 8.5/225 would be 96%. Is that too much rim? 8.0/225 comes out to 90%. I would expect that the tire design would come into play on this. Something with stiff, straight sidewalls would probably be better off with a wider rim whereas a more traditional radial with the rounded sides might be better off on a slightly smaller rim. At least that seems reasonable to me, but I could be out to lunch.
Fourthmeal, is there any rule of thumb for optimum rim/tire width ratio?
The factory 7.5/215 works out to 88% rim/tire ratio, 8.5/225 would be 96%. Is that too much rim? 8.0/225 comes out to 90%. I would expect that the tire design would come into play on this. Something with stiff, straight sidewalls would probably be better off with a wider rim whereas a more traditional radial with the rounded sides might be better off on a slightly smaller rim. At least that seems reasonable to me, but I could be out to lunch.
