[s-cars] Bilsteins and oil in the strut tower

[Rich Assarabowski]

Autocrossers and track guys pretty much agree that Bilsteins are a higher
quality shock and an inherently better design (single-tube) vs the Koni's
(twin tube).  I have Bilsteins on my Miata and they have a reputation for
long-life and reliablility.  I think Chad may have solved the mystery of
their premature failures in the S-cars by putting a drain in the strut tower
before installing them.  My strut towers were full of oil when I pulled them
out.  The resulting hydrolocking would also explain my premature failure of
the strut mounts (as well as the missing tapered caps) which you have to
make sure you install after you remove the OEM struts.   These is the part
that directly rests against the rubber of the strut mount and helps to
distribute the shaft load on the rubber.

The big advantage of Koni's for autocrossers, at least, is that they're
adjustable, but even so, the street Koni's (yellow ones) are just
single-adjustables (compression and rebound change together).  Almost every
nationally competitive stock Miata uses double-adjustable Koni's or
Penske's, but now you're talking $4000 for a set of 4 shocks, if you really
want to win Nationals.

I think revalved Bilstein's with a hole drilled in the strut tower (thanks
Chad!!) is the way to go for non-stock springs (H&R's) for the S-cars.  I
think out-of-the box Bilsteins are perfect for a stock or '92 suspension.
When I was making the Koni vs. Bilstein decision for my S4, guys who had
tried both seemed to prefer the Bilsteins for their less harsh ride.

-- Rich A.
   '99 Miata (CS autocross car)
   '03 MS3
    No more Audi :( (for now)