It’s always the little things that trip me up. The 1/4 inch clearance difference between
the S4 and S5 water pump housings for example. Well I had a similar problem with the suspension.
I had lowered the car down to approximately the lowest legal limit by
trimming one of the front lower spring seats to let the seat spin a few turns lower on the threaded
collar. Sure it lowered the ride height of the car but now I had a tire rubbing issue since the
lower collar was now in line with the sidewall of the tire...rats! In the short term I slapped on
a pair of 8mm front spacers but I’m not keen on the idea of using the spacers even though I run
longer hardened wheel studs. I was in need of shorter front springs to raise that lower collar
up and out fo the way of the tire sidewall. My current spring length was 7" so I needed a 6" spring.
But this raises another issue in that there will not be sufficient spring/suspension travel to
preclude binding of the spring...even when using a stiffer spring. In dialogue with the folks at
Ground Control apparently this is not an uncommon problem and they had just the spring for me.
A 6" spring with a barrel shape to it. The barrel shape allows greater travel than the straight 7"
spring I had on there previously. Since I was going to have to replace the springs to deal with
the ride height issues and to compensate for the “shorter” springs I decided to go a bit stiffer
over all and bump the front spring rate from the 400lb/in front spring and 275lb/in rear spring to
a 440lb/in front and 325lb/in rear spring. The 440lb/in is a conversion from a metric spring rate
and hence the unusual number. 450lb/in was my target but I’ll settle for the 440lb/in spring.
Additionally to get the rear lower spring perch back into a usable position I opted to go with
a longer rear spring as well from 7" to 8" length. In summary I shifted from a front 400lb/in
x 7" spring to a 440lb/in x 6" spring and a from a rear 275lb/in x 7" spring to a 325lb/in x 8"
spring. The cost of the new springs: $280.00. This solved both an tire interference problem
and gave me greater flexibility with ride height adjustments. Time will tell if I chose better
On a side note I've also experimented with using a smaller diameter tire to address
both ride height and gearing issues. The pic below shows the relative differences between a
225/45 R15 tire and a 225/50 R15 tire. The 225/45 tire beig considerably shorter!
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This page last updated June 10, 2006