Blocked grill and "monster teeth"

Made a few changes in the grill area of the car. First of all, I bought a tow bar (from Harbor Freight) and mounting bracket (from Renenmetal) so that I can easily tow the car to events.

Miata's originally come with bracket on the sides of the grill area to tie the car down during transportation. They are known among the Miata aficionados as "baby teeth"and removing them is a mark of an enthusiast. My donor had them removed, but the tow bar mount came with "super sized" mounts. So rather than baby teeth, my car has monster teeth. I also wired up a trailer light wiring harness so the car's tail lights work while being towed.

Later, I got the bright idea to block the grill to improve the aerodynamics a bit. I bought a sheet of aluminum at the hardware store and after making a template, cut it to size. It took a while to get it to fit right. I used some leftover vacuum hose to cover the bottom lip.
I was going to paint it flat black, but I liked the aluminum look - it reminds me of an early 60's drag racer.
Seems to help as my range on the street appears to be about the same as on the highway.

SFEVA meeting thoughts

The August San Francisco EV club meeting was focused on conversions, and Dale Miller asked me to talk about this project. I was pretty honored to be invited - it was only 2 years ago that I knew nothing and now I'm being asked to play expert. Luckily Lawrence Rhodes (who I knew from his postings on a number of EV discussion lists) was there to keep me honest. There were a surprising number of really good questions from the group - obviously a lot of people there were seriously considering a conversion and were deep into the research phase.
During the introductions someone mentioned they were doing 2 AC 914 conversion . I should have made a mental note of this, but instead rambled through why I didn't choose a 914 or an AC conversion and later realized that since I was in the role of an expert, I might have offended him. If so, I apologize.
But what I did want to mention here in the blog was some details around the Miata's specs. One of the questions that came up was around the curb weight of the first generation Miata. I, of course, being unprepared gave an answer I thought was right, but was, in a word, wrong. I have since looked it up and found the Gross Vehicle Weight is 2700 lbs. (on the door jam sticker) and the curb weight is listed on edmunds.com at 2116 lbs. So what does this mean? The curb weight is the weight of the car with fluids and a full tank of gas. I believe in 1999 the government also wanted to include the driver weight of 150 lbs, but this is a '92, so no driver is included in that 2116 lb. figure. The Gross Vehicle Weight (GVW) adds the weight of a driver, passenger and cargo and is intended to represent the maximum weight the car is designed to carry. I have heard some EV conversion shops talk about not exceeding the GVW in your finished EV, or you might have structural problems. Of course, those can be mitigated by strengthening the car's frame, but it's still a good rule of thumb.
The other question that was a stumper was on Miata's aerodynamics. I like to say the Miata has good aerodynamics, but when asked for the figure, I drew a blank. I had to look this up again, and found a listing on Wikicars.org that said " The body was reasonably aerodynamic, with a Cd figure of 0.38." Now .38 isn't particularly good, but it's better than a Triumph Spitfire, but not quite as good as a '99 Mustang (http://en.wikipedia.org/wiki/Automobile_drag_coefficients). I suspect that a modification or two (like a belly pan) might improve this substantially. I guess I'll try to say the Miata has OK aerodynamics...
So thanks agian to Dale for inviting me and the attendees for putting up with my rambling talk. Hopefully someone got something out of it, and don't forget to question authority.