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Super Coupe Club of America > SC Literature > How Low Can You Go?

by Rich Thomson

The Thunderbird Super Coupe is an excellent handling car but how low can you go? Many club members have asked what are the best tires and size for my SC. I know that I've heard about 10 different answers to this question so I will try to give you some info about lowering and choosing a tire size for you SC.

The stock tire size and rim for the SC is 225/60/16 (26.61" tall) on 16x7 inch rims. This provides acceptable handling but as we all know the car looks so much better when the wheel actually fits in the wheel well. FoMoCo choose a tire size that is 26.61" tall with a 7.30" tread width.

Eibach springs are the late model T-Bird springs that I have chosen for discussion . These spring will lower your Thunderbird SC approximately 1.50" and are progressive rate springs. These springs will work with any of the most popular tire sizes (225/60/16, 225/55/16, 245/50/16, 255/50/16). Tire sizes that are for 17" and 18" rims will not provide greater overall tire height equal to or greater than the stock tire height of 26.61", but will provide a wider tread width than stock.

This brings us to the dilemma of how low can you go? I will give you some tire sizes and let you decide for yourself. Stock riding height is about 7.00" (taken from the side valance). 225/60/16 is 26.61" tall with a 7.30" tread width so if you choose any of these tire sizes you will be lowering you car accordingly... The tire size 225/55/16 is 25.75" tall with a 8.20" tread width, while the tire size 245/50/16 is 25.67" tall with a 8.90"tread width and the tire size 255/50/16 is 26.06" tall with a 9.30" tread width. If you subtract half the difference in tire height from the stock tire high you will see the reduction in vehicle high as a result of changing tire sizes. 225/55/16 is a tire height reduction of 0.86", 245/50/16 is a tire height reduction of 0.94", 255/50/16 is a tire height reduction of 0.55". Slight variations in sectional width and tread width can happen between tire manufactures. This information is intended as a reference only.

If you added the Eibach springs and the below tire sizes you would reduce your 7.00" ride height to the following...

Tire Size
Eibach Springs+Tire Height Reduction=Total Ride Height Drop
Stock Ride Height-Total Ride Height Drop
Final Ride Height
225/60/16
1.50"+0.00"=1.50"
7.00" -1.50"
5.50"
225/55/16
1.50"+0.43"=1.93"
7.00"-1.93"
5.07"
245/50/16
1.50"+0.47"=1.97"
7.00"-1.97"
5.03"
255/50/16
1.50"+0.27"=1.77"
7.00"-1.77"
5.23"
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Document Last Modified: 07/29/04 03:33 AM
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