Standard Rim Width

[Dessertrunner]

Does any one know what the standard rim width is I want to go to wider tyre such as 235 but not sure if they will fit.
Tony

[svxfiles]

Originally Posted by Dessertrunner

Does any one know what the standard rim width is I want to go to wider tyre such as 235 but not sure if they will fit.
Tony

Subaru lists it as 7.5 inches.
I have 245/45/16 on several sets of stock rims for years now.

[AGREENTREEFROG]

subaru says 7 1/2 x 16

with a stadard tyre size of 225 50 16

so yes you should squeeze 245 s on there

['E']

my new wheels are 19x8.5 with 275/30 rubber all round and the standard tyres are 235/60

[LetItSnow]

I have to ask you guys how you fit all that rubber in there... Check out the bottom of my sig and find out why.

[svxistentialist]

Originally Posted by LetItSnow

I have to ask you guys how you fit all that rubber in there... Check out the bottom of my sig and find out why.

Is that totally standard 225x50xR16 Let it Snow?

Because if that [narrowish] standard height and width tyre is rubbing, the only explanation for that would be the offset on the wheels you are using must be wrong or a little off standard.

I have seen it posted that the RX7 rims are a substitute, I think this applies to RX7 rims after '92, the one designed in California. Maybe the offset is close but not exactly the same?

Also, something to watch for is tyre profile. Some manufacturers tyres can be wider than others, even if exactly the same size such as 225x50xR16.

Joe

[LetItSnow]

IIRC, stock offset is 55mm. The RX7 wheels are 48mm, which will work against me for 7mm. Tire Rack recommends 48mm wheels from their selection, as a benchmark.

My tires are 225/50/16, with a section width of 9.2". They're measured base on a 7" wheel. Tire Rack advises that for every 1/2 inch larger, you add 2/10". As the wheels are 8", that would be 4/10" whole, bringing my section to 9.6".

Essentially, from the center of the wheel to the outer face of the tire, that's (9.6"/2)-48mm=2.9", or 74mm.

Correct me if I'm wrong, and compare to what your car is wearing if you will?

[svxistentialist]

Originally Posted by LetItSnow

IIRC, stock offset is 55mm. The RX7 wheels are 48mm, which will work against me for 7mm. Tire Rack recommends 48mm wheels from their selection, as a benchmark.

My tires are 225/50/16, with a section width of 9.2". They're measured base on a 7" wheel. Tire Rack advises that for every 1/2 inch larger, you add 2/10". As the wheels are 8", that would be 4/10" whole, bringing my section to 9.6".

Essentially, from the center of the wheel to the outer face of the tire, that's (9.6"/2)-48mm=2.9", or 74mm.

Correct me if I'm wrong, and compare to what your car is wearing if you will?

There are two things here that will work against you, as you say.

One is the 48mm vs 55 mm offset.

The other is the change from 7.5" standard rim to 8.0" new rim.

As you noted, the 55mm positive offset allows a lot of the rim to disappear into the arch closer to the car centre. A lesser offset of 48 mm will have the outside of your tire 7mm closer to the fender [than standard] on the outside.

Then, take into account your new rim is wider by 1/2". So each half of the rim from the centre is wider by 1/4". This is equivalent to 6.35 mm wider on the outside of the rim, and the same 6.35 mm wider on the inside.

Naturally the 6.35mm wider on the inside will be cancelled by the smaller positive offset you are using, and will not foul anything.

However, on the outside next the fender you have gone 7mm farther out with the offset plus 6.35mm out by the rim width. This is almost 14mm out nearer the fender, and it is obviously enough to foul the fender. I suspect this happens when you have the wheel turned and the suspension compressed under load, probably not all the time?

I'd expect going down to 45 profile might cure that.

Joe

[Dessertrunner]

I appricate your replies, what I am doing is different to every one else as I need to go to a bigger tyre because I need a Kevlar side wall. On the rocky roads I am still damaging the side walls etc, also looking for a bigger bag to handle the corragations. The tyre I want to change to is Wrangler Silent Armour 235/70R16. To do this I will have to increase the clearance of the wheel at the back. Should be fun, will let you know how it goes.
Tony

[Nevin]

I would think that you could put a 255 width tire in there, but with a sidewall of a 70 ratio there is no way. You'd maybe be able to get like a 215/75R16 if you're looking for a tall tire. Not sure if there is such a size though hahhaha, and I work at a tire shop. I'm sure you could order something though.

Actually, I do know of some 225/ 75 R 16's so, I'm sure there is hope.

For what it's worth, I run 245/45R16 Bridgestone Potenza RE750 tire on the 8" RX-7 rims. I absolutely LOVE the combo.

[svxistentialist]

Tony

Could you not live with either a 60 series tyre, or else do the unthinkable; go back to a 15" rim?

The tyres on my RVR [click vantastic ]are almost van-like. They are tall-ish with a relatively small rim. Size is 205/65/15.

The more sporty RVR with the turbo engine [which I am getting next!] has a slightly bigger wheel. Comfort over speed bumps and bad roads is fabulous. I'm never going back to licquorice strips any more. Well, nothing lower than the SVX 50 profile anyway.

Joe

[svxistentialist]

Originally Posted by Nevin

I would think that you could put a 255 width tire in there, but with a sidewall of a 70 ratio there is no way. You'd maybe be able to get like a 215/75R16 if you're looking for a tall tire. Not sure if there is such a size though hahhaha, and I work at a tire shop. I'm sure you could order something though.

Actually, I do know of some 225/ 75 R 16's so, I'm sure there is hope.

For what it's worth, I run 245/45R16 Bridgestone Potenza RE750 tire on the 8" RX-7 rims. I absolutely LOVE the combo.

Nevin, you are running the same rim as Let it Snow, but 45 profile vs his 50 profile.

His are fouling the fender. Do yours work OK with the lower profile, or do they grind at times?

Joe

[Dessertrunner]

Joe I need to go to that size as all the smaller tyre sizes don't offer Kevlar except the rally tyre and they are two small for me to get the ground clearance. I run 215/60R16 Goodyear light truck and they are great except that the side wall fails. I also feel that if i could run a bigger bag I might be able torun a lower pressure which should help the vibration road noise. Should have a tyre on rim here tomorrow so may be I will post pic of the problems I will have fitting. One thing for sure with the SVX on the right tyres and the handling it has should make for one hell of a fun time "Flying" over the sand dunes.
Tony

[svxistentialist]

Originally Posted by Dessertrunner

Joe I need to go to that size as all the smaller tyre sizes don't offer Kevlar except the rally tyre and they are two small for me to get the ground clearance. I run 215/60R16 Goodyear light truck and they are great except that the side wall fails. I also feel that if i could run a bigger bag I might be able torun a lower pressure which should help the vibration road noise. Should have a tyre on rim here tomorrow so may be I will post pic of the problems I will have fitting. One thing for sure with the SVX on the right tyres and the handling it has should make for one hell of a fun time "Flying" over the sand dunes.
Tony

I see what you mean Tony.

You are as mad as a hatter, but I like you

Keep us posted on what works.

Joe

[Hocrest]

On the racer we had 275's fitting under the un-modified rear fender by using Impreza struts. They lifted the rear by about an inch. Sounds like doing that may take care of two problems; wheel fit and ground clearance.