Tire pressures should probably be pretty high...38-40 all around, maybe. Ideally we would do a test from 120 down, but personally I don't want to have one hand off the wheel using a stopwatch at 120 mph, in addition to possible legal issues. :) 110 or 100 maybe, as it takes a LOT less time to get up to those speeds, and many of us live in fairly, uhh, cop rich environments. Really anywhere above probably 50 or 60 mph aerodynamic drag is going to be the main factor. Whatever, we know approximately what the drag coeeficient is (.34?) so we should be able to back out our rolling resistance and do some interesting things with the data.
I'm also interested in big vs. small bumper drag. I wonder which is really better... I have Matlab with the stat toolbox too. :) IMHO, Matlab is da shit for engineers. The image and signal processing toolboxes are so friggin' cool. The course I took in matlab was probably the most useful class I've taken. Excel is probably the easiest for this, though, especially since lots of people will want to look over the numbers. I'd be happy to crunch the numbers...shouldn't be too tough at all since we can't possibly get more than 50 or 60 data points (I know, I know, it's not really going to be a large enough test group). Whatever we do, it'll be neat to have a baseline estimate of drag so that any future aerodynamic improvements can be compared to a known quantity in some way. :) >Great idea! If feasable, a higher speed test should be run, so that >aerodymenic drag is the main factor, not rolling resistance. I'm glad >you brought up the issues of tires and suspension; with enough data >points (cars) these effects should average out. However, the largest >source of error (tire pressure) should be standardized. Who want to >crunch the numbers? Excel should be able to do it, although I have >Matlab (with the stat toolbox) at my disposal ;). > >Data to include: >car type >tire size and pressure >final drive >suspension lowering > >Sounds like fun. > >W. Lee Hendrick > >[email protected] >http://soliton.ucsd.edu/~hendrick/ > > ************** Patrick Austin [email protected] (617)493-6636 ************** _____________ List Sponsor: http://www.netsville.com To remove yourself from this list, send mail to [email protected] with 'unsubscribe a2_16v' in the body of your message See us on the web at http://www.a2-16v.com Visit the 16V Homepage at http://www.gti16v.org
