Lower profile tyres

[charv94]

I don't know if anyone has done this and would welcome any feedback or opinions.

has anybody changed from the 40mm standards on the 18 austin or even cadiz to a lower profile tyre. i like the look of lower profiles.

Is it possible to do it? any experience?

[monkeyhanger]

You can't change the profile and stick with an 18" wheel - you'll reduce the radius of the wheel if you go for a smaller profile, your speedo will over read, your mpg will suffer and you'll be effectively gearing down your car.

[charv94]

thats the end of that then.

Thanks

[Exonian]

As MH says, it's just not going to work on standard wheels.
You'll end up with the speedo completely out, scraping the car's belly on the floor and massive gaps in the wheel arches.
On the plus side, the lower gearing will make it accelerate like a demon!!!


The 40 in the profile is a percentage of the width of tyre.

Your options are to do a) what I did and get 19" alloys which will then require 19" tyres with a lower profile to keep the same rolling radius or b) keep the standard tyres but fit wider alloys that will make the tyre sit more squarely making the profile look a bit lower. 225/40 tyres on an 8" wide wheel will look lower profile than on a 7.5" wide wheel like the Austin (just about, if you squint really hard!)

[sweel]

As MH says, it's just not going to work on standard wheels.
You'll end up with the speedo completely out, scraping the car's belly on the floor and massive gaps in the wheel arches.
On the plus side, the lower gearing will make it accelerate like a demon!!!


The 40 in the profile is a percentage of the width of tyre.

Your options are to do a) what I did and get 19" alloys which will then require 19" tyres with a lower profile to keep the same rolling radius or b) keep the standard tyres but fit wider alloys that will make the tyre sit more squarely making the profile look a bit lower. 225/40 tyres on an 8" wide wheel will look lower profile than on a 7.5" wide wheel like the Austin (just about, if you squint really hard!)

Not sure you'd notice that as the profile of the tyres is only visible side on from where you can't see the width so much. Other than a slight angle to the sidewall?


There could also be issues of clearance and maybe even manufacturer specifications etc for insurance etc although not sure how strict this is. (For example are the 18s on a golf r the wider width, I guess if they are then it's ok)

But yes, the 19inch option seems the simplest to achieve the OP's aim.

[Exonian]

There's plenty of room to fit wider alloys sweet.
You can get away with at least 12mm wider on the front and getting on for 20mm on the rear with no issues so an 8 or even an 8.5 inch wheel fits no problem. A lot of German retailers sell 8.5 inch wide alloys TUV approved for mk7 Golfs which means they will pass the strict German MOT.
A 225 tyre on an 8 inch wheel will sit very square getting rid of the slight sidewall bulge you get with a 7.5 inch rim making the profile look fractionally lower and just tidying the look up a bit. The devil is in the detail!