14"s and 15"s
With the exception of the 8v XR2i, all the performance MK3 Fiestas came with 14" rims and 185/55 tyres, the RS Turbo and RS1800 came with alloys as standard, an option on the Si and XR2i. RS Turbo alloys are popular and easy to get hold of, costing around £250 a set. It's cheap and easy to switch up one size to 6.5x15" / 7x15" rims and 195/50 or 195/45 profile tyres. The 45 profile will keep the correct rolling radius as not to affect the speedo reading, but are more expensive and also don't fill the arches as much. There are loads of rims available in this size such as the Escort Si / GTi style, one of the smartest is the style fitted to the MK5 and early MK6 Escort RS2000. These rims are available for around £350 a set. They look especially good when polished, as shown in the photo below. No arch work is needed to fit 15's It is also possible to lower by 90mm with this size of rim, although arch work will be required if you drop it by more than around 65mm.
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RS Turbo running standard 14" rims. |
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RS Turbo with polished 15" Escort RS2000 rims. |
16"s
The next step is to go to 16" rims. In order to fit these without rubbing it is necessary to modify the rear suspension cups and shave or roll the arches slightly. Alternatively a suspension kit that uses coilovers, such as the Spax RSX and Koni kits, will give the clearance required. 16s are a good compromise between looks and handling, they are big enough to imporve the looks of the car dramatically, but not so big as to cause unwanted handling side effects. Popular rims in this size include the 7x16" Mondeo Si and 8x16" Escort Cossie rims can be fitted with major mods and look stunning, as demonstrated on Ravinder Khalon's RST.
You can see in the photos below how much difference 2" can make to the overall look of the car.
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RS Turbo running standard 14" rims |
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XR2i Turbo with 16" TSW Imolas |
17"s - Click here for the guide to fitting 17"s
A Lot of people will tell you that you can't run 17" rims on a Fiesta. The truth is you can but most are not willing to put in the time and effort to make them fit. I have seen at least 15 different Fiestas running 17's, all lowered and one dropped by 115mm.
To get 17" rims on requires the same arch mods as 16's, but the arches need more work, the front inner arch liners also need to be removed. however it's still possible to drop the car by 60mm or more as seen on many magazine featured Fiestas. 17's fill the arches perfectly and look just right although the speedo will give false readings, according to my calculations this can be resolved by fitting 150mph RS Turbo dials as explained in this maths lesson:
Let's say for example the car is running on the original 14" rims and 185/55 tyres, the rolling diameter of this combination is 19.75". When the wheels are changed to 17" with 205/40 tyres, the rolling diameter becomes 21.25", a 7.5% increase. This causes the speedo to under read by 7.5%. When the 140mph XR/SI dials are used, 70mph is halfway in the 0-140mph range, and will show as 65mph. With the RS dials, 75mph is halfway in the 0-150mph range, 7.5% of 70mph is 5.25mph, so on the RS dials this will read as the correct 70mph.
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RS Turbo with 17" Smith's Revolution |
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Si with 17" TSW Trophy |
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RS Turbo with 17" TSW Evo R |
Rims of this size can affect the handling somewhat. Firstly the acceleration of the car will be slower than before. A rough estimate would be adding a second to the 0-60 time, however, the top speed will increase slightly. Torque steer will increase, as will road noise. The ride quality will deteriorate due to the lower tyre profile, and the car will tramline quite badly (act like it's running on rails).
The larger rolling radius of the rims will also cause the odometer to under-read, so the car will cover more mileage than will be shown(!). Top rims in this size include TSW Imola and EVO R, Kosei Racing Seneka, S5R and Senaka Sport, Wolfrace Voodoo, Smiths Revolution and Infinity, Momo Sport and Arrow.