I've been picking away at race prep for the upcoming Lemons race at Gingerman in a couple weeks. After years of racing our SHO and never quite having the spare parts we needed, I've gone off the deep end making sure I have just about everything on the car duplicated - which after loading it all up in the truck should ensure that I need none of it once we're at the track. I'm a big fan of the "bin system" meaning like parts go together in labelled rubber bins of various sizes. I have new brake rotors, pads, and calipers in a box. Engine sensors and ignition coil. A clutch and throw out bearing and wheel bearings for each corner. A box full of spare cooling system hoses and gaskets. You get the idea - this matches the flavor of bins I have for electrical stuff (multimeter, strippers, crimper, terminals, heat shrink, tape, and misc wire) and fastening stuff (hose clamps, rivets and gun, duct tape, zip ties, safety wire and pliers) that ride in the bottom shelf of the 5 drawer service cart that holds all the tools.
I found a German specialist parts recycler about an hour from me that had two 318ti cars in various states of dissasembly. Because he wanted the parts gone, I got a pretty good deal on all the driveline components except a driveshaft, as well as front knuckles and rear subframe with trailing arms.
There are two differentials, one 3.45 with a worn out limited slip and one 4.10 open diff. The guy is getting out of re-building differentials, and threw in the clutch packs to re-build both this one and the 3:45 that's in my car currently. The plan is to build a 4.10 LSD over the winter and put it in the car for next season. I'll also go through the engine and trans and put them in the car when they're fresh. The front knuckles will get fresh wheel bearings and hubs and be ready to go as spares. The rear subframe will be built up with new bushings, trailing arms, bearings and hubs, then be assembled with a differential, axles, and brakes and be on a pallet ready to go into the car as an assembly if needed.
The first major maintenance order before this upcoming race was to diagnose a drivetrain vibration that the car had at certain speeds. I suspected the guibo, center support beraing, or worse - the u-joints. These driveshafts are thin on the ground, and new ones are almost $700. I was relieved when I got under the car and saw the guibo was about to let go. The new (OE from FCP Euro) part I had on hand was installed. The center support bearing was in good shape, as were the u-joints.
I changed the transmission fluid (Redline D4 ATF) and differential fluid (Redline 75W90). The differential had a lot of particles on the magnetic drain plug. I re-built this differential two summers ago, with all new bearings. I'm not sure where these particles came from, but there weren't any chunks, and the gear teeth all look fine. I'm hoping it will hold up for one race weekend before I can swap in a newly re-built unit.
I continued the interior cleanup by adding some panel edging to the sharp edges of the doors, which were left behind when I cut out the center portions. I didn't have time to really clean the inside or paint them, but that can come later, along with revised handle pulls (cables).
I installed Bimmerworld's non-M E36 brake duct kit and universal bumper ducts. I don't love the fit of the ducts with my airdam, but this will work for now. I'll probably re-do it at some point. The backing plates at the knuckle/brake are really nice. Hose routing is an issue though, as I can't turn to full lock without the tire rubbing the hose. It is fine at track steer angles, but paddock and trailer loading will be a concern. I should figure out some sort of rub shield for them.
All that really remains is draining the coolant and replacing with water, mounting tires, and loading up.