Minimum Weight

Part of building a car to a ruleset is, newsflash, abiding by that ruleset. The SCCA Prepared classes have minimum weights, typically depending on displacement, weighed without the driver. Since I’ve got another month or so before the wiring and ECU / tuning are fully sorted out, I figured it was time to drop the car to the ground and start making sure she meets the letter of the law.

For D Prepared, I now fall under “Engines with 3 or 4 valves per cylinder and displacement greater than 1667 cc:

0.91 x displacement (cc) + 250 lbs.

The 2001+ BP-Z3’s displacement is listed at 1839 cc x 0.91 = 1674 + 250 = 1924 lbs without driver. Yay math! (now I need some Tylenol… my brain not math gud).

The previous minimum weight with the 1.6L was 1693 lbs, which I was just over before the completion of the cage. With the cage, we were way over weight, which is why I went to the 1.8 after realizing that the 1.6 had a cracked block. So instead of being overweight, I find myself with the opposite problem:


1830, you’ll note, is 94 lbs shy of the required 1924 minimum, so now I’ve got to get creative with ballast. I’d like to add ~100 lb of steel, which puts me clear of the target with a small buffer, but I don’t like my buffer being THAT close, as it almost bit us at Nationals a couple years ago. However, between mounting plates for the ballast, some extra fuel (it’s currently sitting at its minimum level), fender flares and a few other bits and bobs, I ought to end up close to minimum weight with a comfortable (but not too great) buffer. I have a few ideas kicking around for mounting various types of ballast, we’ll have to see what shakes out (and also what I’m able to track down as far as items to use for ballast). I’m open to suggestions. I think I might hit up a local used sporting goods store this weekend and see if I can’t find something suitable to use.

In the mean time, here she is on the ground, looking pretty damn good (if a bit dusty) if I do say so myself (and I do).