Derby Tech - January, 1986

by Bruce Finwall

Like it or not, All-American Senior division cars will have a new look for 1986. The new rules call for the cars to be at least 13" wide by 14" high with a minimum circumference of 49". In addition, there will be maximum curvature templates for the top and bottom of each car. For "lay-back" style racers, you must be able to place a template (10" wide by 1 1/4" deep) on the top and bottom of the racer and have the two outside points of the template touch the car (see cars #'s 3,4,5,6)., For "lean- forward" style cars, the template is different (10" wide by 3" deep) and this template applies only to the bottom (see cars #'s 7,8,9)!

Well, if you're thinking about building one of these new seniors, I suggest that you give a lot of thought to your design. At first glance, you'll probably draw design #1, just to see where you stand, that's what I did. Then I came up with designs like #'s 2,3,4,5, and others. But I didn't stop there. After much thought, I came up with #6. Clearly, a car based off #6 should be better than a car based off of #'s 1-5. (When I say "based", I also mean rounding up the shape a little, maybe to 156- 163" squared.)

Now that was for the "lay-backs". For "lean-forwards" you can use #'s 1-6 or you can go even smaller to #'s 7,8, or even 9! In actuality you might be able to go even smaller yet, but remember the kid has to fit. Also, there will be a minimum cockpit opening size of 9" by 18" for "lean forward" racers, thus designs like #9 become impractical unless your kid has a "pencil" neck.

So what design is the best? Unless your driver weighs less than 80 pounds I would say that a "lay-back" variation of #6 might be the fastest If the driver is VERY small the "lean-forward" design may become a viable option.

Note: Bruce Finwall has designed several new All-American Seniors and has plans available for interested families. Write to 30125 Avenida de Calma, Rancho Palos Verdes, CA 90274

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