Effects of alloy wheels

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Sun 13 Apr 2003 13:23
Effects of alloy wheels - Mike200
I now have a 98 s rover 214, running on 14in steel rims. I would like to know the following:

What is the max size alloy wheels i could fit with out altering the arches?
How will it effect the speedo, will it say im going faster than i actually am or slower?
How can i re calibrate the speedo, i assume it has to be done by someone in the know
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Sun 13 Apr 2003 14:02
Effects of alloy wheels - Another John H
What you choose to fit will affect the speedo depending on the change in rolling radius:

If you look at

www.chris-longhurst.com/carbibles/tyre_bible.html

there's calculator in there which will tell you percentage speed differences for a given pair of wheel and tyre sizes.
If you choose carefully you won't need to alter the speedo.

In terms of maximum sizes, you'll have to wait for someone who's done it on that car to come along, or find a tame tyre and wheel shop...
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Sun 13 Apr 2003 20:22
Effects of alloy wheels - IT
by increasing tyre size and width, u have altered the speedo setting. my mate put 19" rims on his car two weeks ago and dident get his speedo altered. the next week he got stopped for doing 115mph on the motorway when his speedo said he was doing 90mph!!

also the road noise and handling of the car changes. plus u also get alot of wheel wobble!

regards
IT
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Sun 13 Apr 2003 20:41
Effects of alloy wheels - DavidHM
If you put the right tyres on, so that the total diameter stays the same, you don't need to adjust the speedo.

Alloys that are too big, although they would fit, may not be optimal for handling and almost certainly won't be for ride.

Personally, although big wheels look great, I wouldn't go above 16" on a car like that, and 15" is probably more practical. That is if you actually drive the car, rather than just pose in it.
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Mon 14 Apr 2003 00:25
Effects of alloy wheels - Dynamic Dave
by increasing tyre size and width, u have altered the speedo
setting.


The tyre width won't make any difference to the speedo reading at all as you haven't increased the circumference of the wheel.
also the road noise and handling of the car changes.


Yes; on dry roads handling will be improved as you've increased the footprint you make between car/raod. However on wet/snowy roads a bigger footprint isn't always best, so the handling will suffer. Horses for courses really.
plus u also get alot of wheel wobble!


Only if the wheels/tyres aren't properly balanced.
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Mon 14 Apr 2003 10:08
Effects of alloy wheels - blank
>> also the road noise and handling of the car changes.
Yes; on dry roads handling will be improved as you\'ve increased
the footprint you make between car/raod.


On dry roads the level of grip will probably be increased, but the handling will probably be changed for the worse. It will be snappier on the (higher) limit.
However on wet/snowy roads a bigger footprint isn\'t always
best, so the handling will suffer. Horses for courses really.


On snowy roads big foot print IS bad. On very wet roads, you will aquaplane at lower speeds with wider tyres.
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Real MPG enables you to register the fuel economy you are actually getting against your make and model of car, its engine and type of transmission.

Every time you enter an average consumption figure against your car, the overall average automatically adjusts to reflect it.

Real MPG