...with me replacing my stock '96 FE front spring with a stiffer '91 FE front spring?

I am probably going to lower my car this Spring with the standard polywedge-style kit. I already have a front spring from a '91 FE convertable car that is in great shape and has already had the thick stock rubber mounting pads cut off. In general, I wouldn't mind a slightly stiffer ride and I thought that the stiffer front spring would help me to keep from bottoming out after the car is lowered. I would also have the added bennefit of being able to keep my stock spring unmodified in case I cannot stand the car lowered.

The car currently has the stock '96 FE suspension with new Koni yellows and wheels/tires in Grandsport sizes. I am also planning on going to heavier sway bars some day (such as the 30mm & 26mm solid bars from from DRM).

The car is a weekend/fun street car that will go to the track (road / autocross) occasionally. It is driven fairly often, but is definitely not a daily driver. I want a firmer feel when cornering without being overly harsh and skipping off the road when a bump is hit.

Here's my question to you suspension gurus: What adverse effects will I see if I go with the stiffer spring in the front, but do not replace the soft '96 FE rear spring? Would I be better off waiting until I can buy a rear spring that is matched to the front?

It will be awhile until I'm able to do the sway bars or the rear spring, but if there is no reason not to, I can do the lowering and stiffer front spring now.

Any insight will be appreciated!


David

 

The stiffer front spring will increase the front roll stiffness. Increasing the front roll stiffness without increasing the roll stiffness in the rear generally causes an increase in understeer in hard turns. I would replace the springs in pairs.

 

I agree with the analysis.

However, the decision about whether to change springs in pairs or
singly and if singly, at the front or rear first, should be determined by
the current behavior and the desired objectives.

If the car currently understeers and the rear suspension bottoms over
large dips, my vote is that increasing the rear spring rate would be a
worthwhile first step and it would be physically simpler/faster, as well.

.

 

 

DCP, checkout the rear spring rate of my 84 FE1... have any interest in purchasing or trading?
I'm trying to go "soft" for my daily driver - pls let me know either way, thanks Brett

 

dabrettster,

Thanks for the offer, but I'm pretty sure yours is way to stiff for what I'm looking for. Looks like I need around 39N/mm to stay matched to the 93N/mm front I want to use.

David

 

Thanks for the advice guys. The car feels soft but fairly balanced right now, but a trip to track to get it closer to the limits will tell me much more.

I think for now I will cut the original spring for the lowering and see what happens, then add the heavier sway bars, then see if I still think new springs (matched set) make sense.

Thanks again,
David

 

Thanks for the quick reply David. The offer will remain open, so keep me in mind as you're tuning. If you find you want to further reduce understeer, squat, or excessive weight-jacking, then you may want to reconsider the 84 rear spring.