With the experience of the first trackday earlier on, a few upgrades went into the car.
First of all, we got rid of the Bilstein setup that clearly isn’t developed for track use. A brand new BC Racing extreme low coilover suspension was installed all around. The extreme low struts allow an extra 2 inch of lowering over the
standard version, which is quite handy for a track car. The lower the point of gravity, the less body roll. At the same time the rear subframe was modified with one of our camber/toe kits, so that the suspension geometry is now fully
adjustable. When extremely lowering any E21, the rear wheels have way too much negative camber and the toe-in is also completely messed up. Our camber/toe kit has massive adjustability and allows to set the geometry to wherever you
want it to be.
Another upgrade was the installation of a set of E30 rear brake calipers. This is quite straightforward and requires only small modifications to the calipers. The advantage is especially the choice of available pads for these calipers,
something you don’t seem to find for the original E21 ones. The
pads have slightly bigger surface as well. While installing these calipers, the brake pressure regulator was eliminated and braided lines were also installed in the
rear. All of this really helped a lot to restore the brake balance of the car. Before the front brakes were doing all of the work, now you can feel that they are supported by the rear ones and the car brakes more ’square’ look
it’s supposed to do. We still need to replace the standard brake fluid with the racing type one. When really hammering the brakes, they finally start to fade as the brake fluid reaches its boiling point.
One last investment is a set of Federal semi slicks.
With all of the upgrades in place, we did a trackday at Circuit Zolder. The car performed exceptionally well. A new list of improvements is already waiting. Polybushes and better cooling are on the list along with removing most of the
interior to lighten the car somewhat. Once the chassis and brakes are fully sorted, some power upgrades will be considered, but first things first.