Tuesday, April 20, 2010

Springs

Well, it's become clear that I have to get new springs for the front end of the car. The other day I went over a speed bump and it bottomed out on the way down. Ouch.

I measured the ride height of the car before I started the project, and I also had it weighed (as you may remember). After the conversion was complete, I measured the ride height again and found that it was riding 3/4 of an inch lower than before. I started looking into different springs available for the car and found that they were all designed to lower the ride. Most by an inch or more. With that in mind, I was perfectly happy with the 3/4" I was seeing.

But then I started looking through the service manual and found out how BMW measures the ride height. It also listed what the ride height should be. I measured it the way they recommend and found that it was over 1.5 inches lower. Now my original measurement wasn't off, so that can only mean one thing, the car was already 3/4 of an inch lower than stock before I started. I haven't pulled the car apart yet to verify that there were already aftermarket springs on the struts, but that's my suspicion.

Oddly enough, the ride on the rear end of the car is at factory spec. Huh... strange.

Well any way, when it bottomed out the other day, I decided I need to do something about it. My neighbor had suggested looking at other BMW's to find out if there was a chassis that used the same spring with a different rating. Great idea! So, this is an E-36 chassis, and the good news is that there are several other models and years built on the E-36 chassis. The bad news is that there were only two heavier than mine, and they were only 100 lbs heavier. So, scrap that idea, that's not close enough to the 386 lbs the car gained.

I've read on the EV Discussion list that most any city has a place that specializes in building springs. Frequented by off-roaders and truckers, these places can take an existing spring and fabricate a replacement the same size but with a different rating. I asked my cousin Tommy (who is in the heavy truck business) if he knew of such a place. He said he didn't, but asked a local shop that sells springs. They had said they could send it out of state, but that they didn't know of a local place either.

So, I'll spend some time tapping into the off-road shops around town and see if they have a suggestion. If not, I guess I'll be sending my springs out of town. Of course, if the springs on the car are aftermarket springs, I'm going to have to get a hold of a stock one that I can send instead. That might be better because then I don't have to disable my car for the several weeks it will take to get the new ones.

2 comments:

Gam0ra said...

The web company I started specialized in selling lift kits/aftermarket parts, etc. It's still in business, so I've sent my ex-partner an email to see if he knows of any source for what you need.

I also told him you'd love to show off your EV Z3 so you may get a visit.

Tim Catellier said...

That all sounds great to me. Thanks!