I've been reading for ages on equivelent tyre sizes, but no-one ever
seems to mention the width of the rim in all this. Surely any given
tyre diameter will change, the narrower the rim it is squeezed on to...
and there must be a guide to safe, or optimum, tyres for a given road
wheel size.. Has anyone ever seen a table listing suitable tyres sizes
to choose from?

My problem is this: I have 175/70 13 on a 5.5J rim on a spitfire and
they rub on the wheel arch lip. So i need to go narrower and/or lower
profile. Any suggestions anyone - my un-skilled opinion says I should
go narrower, as the rear will be left on 175/70's and narrower means
the front wont look noticably smaller.

"nooge"  wrote in message 
news:1123621604.323246.266230@z14g2000cwz.googlegroups.com...

> I've been reading for ages on equivelent tyre sizes, but no-one ever
> seems to mention the width of the rim in all this. Surely any given
> tyre diameter will change, the narrower the rim it is squeezed on to...
> and there must be a guide to safe, or optimum, tyres for a given road
> wheel size.. Has anyone ever seen a table listing suitable tyres sizes
> to choose from?
>
> My problem is this: I have 175/70 13 on a 5.5J rim on a spitfire and
> they rub on the wheel arch lip. So i need to go narrower and/or lower
> profile. Any suggestions anyone - my un-skilled opinion says I should
> go narrower, as the rear will be left on 175/70's and narrower means
> the front wont look noticably smaller.
>


take a look at some of the tyre suppliers/manfrs.  for instance this one:
http://www.tirerack.com/tires/Spec.jsp?make=Sumitomo&model=HTR+200&partnum=77HR3HTR200&vehicleSearch=false&fromCompare1=yes&place=0

Cut and paste as needed

this shows that a 175/70/13 is measured on a 5 inch rim and that suitable 
rims are 4.5 to 6 inch

mrcheerful

"nooge"  wrote in message 
news:1123621604.323246.266230@z14g2000cwz.googlegroups.com...

> I've been reading for ages on equivelent tyre sizes, but no-one ever
> seems to mention the width of the rim in all this. Surely any given
> tyre diameter will change, the narrower the rim it is squeezed on to...
> and there must be a guide to safe, or optimum, tyres for a given road
> wheel size.. Has anyone ever seen a table listing suitable tyres sizes
> to choose from?
>
> My problem is this: I have 175/70 13 on a 5.5J rim on a spitfire and
> they rub on the wheel arch lip. So i need to go narrower and/or lower
> profile. Any suggestions anyone - my un-skilled opinion says I should
> go narrower, as the rear will be left on 175/70's and narrower means
> the front wont look noticably smaller.


If it's rubbing on the lip, why not roll back the lip??

--
R

nooge wrote:


> My problem is this: I have 175/70 13 on a 5.5J rim on a spitfire and
> they rub on the wheel arch lip. So i need to go narrower and/or lower
> profile. Any suggestions anyone - my un-skilled opinion says I should
> go narrower, as the rear will be left on 175/70's and narrower means
> the front wont look noticably smaller.


I had the same problem with my Vitesse when I first got it. Some idiot 
had fitted tyres that were too wide - they may well have been 175s. 
Anyway, I swapped to 155/80 13 tyres as originally fitted (I think) and 
it's fine and looks more sensible too.
I certainly wouldn't fit lower profile tyres to a Spit - they'd have an 
awful effect on the ride, which isn't the most comfortable in the world 
as I'm sure you'll agree.
If you're worried about losing grip from narrower tyres, go for a softer 
compound. You'll have to replace them more often, but they'll be cheaper 
so it'll balance out.

"nooge"  wrote in message 
news:1123621604.323246.266230@z14g2000cwz.googlegroups.com...

> I've been reading for ages on equivelent tyre sizes, but no-one ever
> seems to mention the width of the rim in all this. Surely any given
> tyre diameter will change, the narrower the rim it is squeezed on to...
> and there must be a guide to safe, or optimum, tyres for a given road
> wheel size.. Has anyone ever seen a table listing suitable tyres sizes
> to choose from?
>
> My problem is this: I have 175/70 13 on a 5.5J rim on a spitfire and
> they rub on the wheel arch lip. So i need to go narrower and/or lower
> profile. Any suggestions anyone - my un-skilled opinion says I should
> go narrower, as the rear will be left on 175/70's and narrower means
> the front wont look noticably smaller.


A few years back I had a hillclimb mini with 13 x 5.5's. I used 175/50 13's 
on it as these were the only ones I could get under the arches.

175/70R13 have a diameter of approx 575mm
175/50R13 have a diameter of approx 505mm

These would be around 35mm further away from your arch.  Due to the fact 
alot of these tyres are still used by the mini crowd there are some good 
performance tyres to be had.  Try www.mytyres.net thats where I normally 
start off for tyre size/make availability.

hth

chris

In article , 
nooge says...

> I've been reading for ages on equivelent tyre sizes, but no-one ever
> seems to mention the width of the rim in all this. Surely any given
> tyre diameter will change, the narrower the rim it is squeezed on to...
> and there must be a guide to safe, or optimum, tyres for a given road
> wheel size.. Has anyone ever seen a table listing suitable tyres sizes
> to choose from?
> 
> My problem is this: I have 175/70 13 on a 5.5J rim on a spitfire and
> they rub on the wheel arch lip. So i need to go narrower and/or lower
> profile. Any suggestions anyone - my un-skilled opinion says I should
> go narrower, as the rear will be left on 175/70's and narrower means
> the front wont look noticably smaller.
> 

You can go down two sizes and up one on a rim as a rule of thumb so 
you'll be OK for 155-185.


-- 
Conor

-You wanted an argument? Oh I'm sorry, but this is abuse. You want room 
K5, just along the corridor. Stupid git. (Monty Python)