Suspension Swaps = No Free Lunch

["Duane Collie" <drcollie@xxxxxxxxxxxxxxx>]

>Since I'm not satisfied with the handling of my 92 325is, and the fact that
>the gaps between the tires and fenders are very possibly greater than that
of
>a Land Cruiser, I began the quest for lowering springs. Considering that I
>drive on the worst roads imaginable, and I'm not quite willing to give up
the
>luxo ride, I first looked at purchasing M spec springs to use with my stock
>shocks. These (I'm told) would be lower by about 3/4 of an inch, with a
ride
>slightly better than an M3, which I could happily live with. However,
Bavarian
>Autosport convinced me that a set of AC Schnitzer springs would be slightly
>firmer than M springs (but still not ride as firm as an M3 with my higher
>sidewalls). I was all set to order until I was told that my car will drop
1.25
>inches. The fender gaps will look nice, but I'm worried about scraping the
>nose.
>Will the height be OK, or should I leave the ugly gaps and just get a set
of
>swaybars? Which will improve handling most?
>Matt


Matt,

Welcome to the world o'upgrades where EVERYTHING is a tradeoff.  You can't
have it both ways, i.e., better handling and luxo-ride. That's what BMW does
(very successfully) when they make the car originally.  Anything you do to
increase the handling potential will result in a harsher ride. Bav Auto guys
can barely find their way out the front door, btw - don't rely on them for
mod advice.

Suspension mods SHOULD be done as a package, otherwise you are adding
componentry onto linked items that is not designed to work together.  So
when you use performance springs, you should do the shocks as well so the
damping and spring rates are compatible.  Also, simply sticking on bigger
sways without changing the springs and shocks is of little use.  What good
is tighter and flatter body roll when the car is falling over its
springs&shocks?

One thing rarely looked at in shopping aftermarket springs is the question :
Are they Progressive Rates or Linear?  If they are progressive (like  29910
H & R's) then the first part of the spring is softer than the last part of
the travel.  If they are linear, then the spring rate is the same all the
way through the travel range (harsher ride - better for the track).

Here's an idea for you that is easy to do.  Convert to 17" x 8" wheels with
235/40/17 tires.  Borrow a set of a friend's M3 if you can and test drive
them.  Not only will your car look better, but it will handle much better
with crisper turn-ins and more road feel without having to mod the
suspension. Won't seriously change your ride height, either. Don't like 'em?
Easy unbolt.  Tradeoffs though: More tramlining and you can' blast potholes
or you'll fold the rims up.

Duane Collie
RM3DR1/UUC/Bubba

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