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equivilent tyre sizes - what about rim width?

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.

Reply to
nooge
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take a look at some of the tyre suppliers/manfrs. for instance this one:

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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

Reply to
mrcheerful

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

-- R

Reply to
R

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.

Reply to
Willy Eckerslyke

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

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thats where I normally start off for tyre size/make availability.

hth

chris

Reply to
Chris

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.

Reply to
Conor

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