Monday, May 25, 2009

Suspension work for the e21

I've been using the time off from track days to get some work done on the e21. The front driver's side shock was rattling, so that's out to be replaced. Turns out it was from a 2002, but it is also a Bilstein sport, so better to fix that replace. As with all things Team Orange, it turned out to be much more complicated that it should have been. Luckily, some help from Herbert at Bavaricars saw me fixed for no cost! Just needs to be re-fitted and we're good to go. My wife's, sister's partner is coming down in 2 weeks to drive the e21 at Wakefield, so it needs to be in top condition.

Since I had the opportunity, I've made some adjustable coilovers for the rear of the e21. If I'd known it was that simple, I'd have done it years ago. Doesn't really help with the ride height yet, at the springs are still stock(ish), but is all ready to use the Eibachs when I upgrade the ones in the e12.

Now I've got all the bits, I just need to get them back into the car!
For those that are interested, I've detailed out what I did to make the coilovers:
1. Buy car that happens to have a spare set of Koni adjustable shocks left in the boot with some aftermarket springs! Alternatively, you can buy them. Most Konis are rebuildable, so a decent second hand set will do for starters. Bilsteins have a similar mounting system, but are more expensive. Depends on you wallet and your needs.

2. Measure up outside of shock - these Konis are 42.4 mm.

3. Purchase threaded collars with ID to suit OD measured in step 2. Make sure you also buy spring seats and locking rings. I bought mine from Fulcrum and they were $120 for the two sets delivered to work.

4. Remove existing struts from spares car (or from original car if you're brave enough)

5. Remove lower spring seat. On the Boges, it was just pressed on, so some good solid hits with the hammer got it off.

6. Cut out the centre section to suit the spring seats. In this case, mine are to suit 60 mm ID springs. I cut it out by drilling a series of holes and using a jigsaw.

7. Apply electrical tape to take up 0.5 mm gap between shock and threaded collar.

8. Fit collars and seats to shocks.

9. I trimmed the springs by a couple of mm to remove any preload. I didn't want any, but this is up to personal preference, requirements and springs.

10. Trial fit to make sure it all works.

11. Paint the bits you worked on and put it all together.

One set of coilovers complete. There won't be any downwards adjustment unless you buy a set of superlow springs. Then you could adjust them up for daily driving and down for track or show.