Race setup?

#1

New over here!!! A little bit distant to participate in Spec E30 events, as I am in Puerto Rico. That doesn’t stop my interest in building an E30 according to the regulations. As an experienced SOLO driver, I’ve been running in the local championship for the past two year. Now I make a switch from Subaru to a more reliable and viable platform, a 1990 325i coupe.

As per the regulations I’m going to install a set of H&R Race springs with Bilstein inserts, so I would like to know the expected alignment values (front/rear camber, caster and toe) from there using OEM strut mounts.

Regulations states in section "9.3.8.1. Any adjustable camber or camber/caster plate is allowed, unless specified in these regulations." and "9.3.8.2. Use of eccentric/offset bushings at the control arm pivot points or at the strut-to-bearing-carrier joint is permitted." It’s is allowed to install eccentric bolts or adjustable bushings for trailing arms? If allowed, it’s necessary to use these in order to get a decent amount of adjustment?

Any information will be appreciated.

Carlos

#2

I can answer the 2nd question…

There is ZERO adjustment to the stock rear suspension on an E30. The eccentrics give you that adjustability. There are 2 ways to get adjustment on the rear - a kit from Ireland Engineering (rear camber/caster kit) - it requires some welding and slotting, but is a great solution - in most ways superior to the bushing thing (as they can slip and move after installed), and the eccentric bushings. The Ireland kit is NOT LEGAL for specE30 (but works great on my Z3).

John