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build diary << | show individual entries | >>September 17, 2005: Polishing the spare wheels yesterday revealed that the perfect tool for the job is seveal grades of Scotchbrite (or a reasonable facsimilie thereof) because it's fast and easy to use. The new wheels look good and are being painted now. I also cut up plywood for the new, lower windshield and discovered that the aluminum channel I use for the frame is no longer available in 8' lengths. All I can get is 4' but that's not enough to go around the windshield. Argh. I'll have to find a solution to that.
Westfield, Ultralites, Caterhams, Lotuses, Robin Hoods, Strykers and probably at least one other make I've forgotten. It was very interesting looking at all the various engineering solutions. I pestered a lot of people about their front wheel rates as I'm trying to get a feel for what mine should be. As I mentioned earlier, we had travelled over to Durango in Janel's supercharged Miata. It looked huge. I suspect even my Seven would look huge in that company. The Miata did help a number of Se7en USA drivers to identify me, though. I spent most of the day wandering around and sticking my nose into various jobs underway - sorting out an overheating crossflow, cleaning plugs on a VHPD K-series, trying to diagnose a running problem with a 400 cubic inch Chevy smallblock (yes, in a Seven). Note that I was sticking my nose in, not actually doing anything to help. Still, I was able to help out a couple of cars by sourcing parts that they'll pick up tomorrow in Grand Junction. The most common complaint on the part of the cars was running rich. Carbureted cars were suffering typical high-altitude ills but even some of the fuel injected ones were suffering. They run off pure throttle position instead of using manifold pressure - that's an understandable thing to do with a big cam and throttle bodies. The problem is that it can't deal all that well with massive ambient pressure changes. I hadn't thought of that before, although I had considered running TPS control on my car. Maybe I won't then. I hopped in to a couple of Caterham SVs to see how they fit. One had a lowered floor and was cavernous inside. The level of detail overall was wonderful to see and I may end up fabricating some new control arms from their designs. Much cleaner and lighter than my own. We tucked in behind a group of three cars led by one of the tour organisers and had a high-speed run over Wolf Creek Pass. Turns out a 150 rwhp supercharged Miata can just about keep up with a carbureted 140 crank hp Caterham that's loaded with two weeks worth of luggage and suffering from 10,000' of altitude. Soon after, we let the Se7ens romp off into the distance and took things a bit easier to enjoy the view. The fall colors were at their peak and the weather was perfect, making it a hugely enjoyable trip. One thing I did do over the weekend was measure a number of louvre setups in hoods. It turns out Birkins use 3" holes like I am, so I used one of their cars as a base for my venting design. The other Se7en owners did confirm that 1) the transmission tunnel is always hot and 2) the hood will always lift up above 90 mph, louvred or not. The hood is off being punched right now so I should have it in time for tomorrow's visitation of Se7ens. Let's hope the little orange beastie does me proud. Number one of the Good Ideas To Steal: springs to hold the slip joints together in the exhaust. Some scrambling around yesterday and the hood is now punched with louvres! I had to change the layout a bit because the spacing between the louvres was different than I had assumed. These are hot rod louvres and they're bigger than the ones used by the Seven makers. Still, the layout looks good - except for one small detail. It turns out that hot rods put their louvres facing forwards (why?). Those who know something about aerodynamics put them facing backwards. Well, these were punched by a hot rodder so they're backwards. I just never thought to specify even though we were laughing about how it was important to get them the correct way around. The problem that both of use considered the "correct way" to be different. This will work fine at a walking pace, but at speed it'll actually make the airflow worse than before. I'm going to be very embarassed showing up amongst the Se7ens this afternoon with a backwards hood. Kent, the guy who did the work, has bought a new piece of aluminum so I can fabricate another hood. I'll have to work fast, I'd like to have the proper setup for the race this weekend and definitely for the high-speed trackday at Aspen on the 15th. I also have to change the brakes on two cars. It's going to be a long week. Oh well, if it was easy everyone would do it... Whoops. |