Fast Pinewood Derby kits based on Science
1. Center of Gravity (Center of mass) Location. This step is supposed to give you a 36% increase in speed. Our target setup is for a 0.930" COG in front of the rear axle. We find this the best setup for the bumpy tracks, keeps the nose down and keeps you going down the track. If you do a little research, you can find this is the target goal for the adult leagues.
We use lead with final weight by tungsten putty. Lets face it, tungsten is expensive. COG is COG. When the car weights 15 grams prior to weight; you desire a specific COG; the piece of wood could care less if it is tungsten or lead. This is an author's opinion. Just don't think you are automatically be ahead cause used used tungsten weight.
Just and FYI. All competitive derby parents make sure there COG is in the proper place. So if you have 3 or 4 parents out there that like to win, best chances are they did it too! Sometimes we get a little aggressive and you will need some of the ballast putty towards the front. Lead is Lead. It is unknown. It's always recycled from someone else's project.
2. Lightweight wheels. Author's claim is 16% increase in speed, but I tend to think the increase is more like 36% and COG is 16%. I know if I can use a set of 1 gram wheels and tune a car, I will smoke nearly everything. I will beat any car that has factory wheels no matter if I am racing a block of wood. Seriously.
All our kits come with the options of weight reduced wheels. Please check your rules. Please Check your Rules. Don't blame us for you not checking your rules. But if you can these will determine the maximum top speed of a TUNED car. if you don't tune, then you are shooting yourself in the foot.
3. Aerodynamic. 11% increase in speed. All cars we offer are streamlined. This is a no brainer. With low weight placement. We also remove wood around the wheel's outer edge to ensure that that part never touches the body. We also utilize a tapered front (quick start) that allows for your car to start down the track, before others do. This has been our standard for years.
4. Polished Nails. 10% increase in speed. We got that covered. Our axle line is simply the best polished axle on the market today. All CNC work done to our standard axle. We even CNC polish our axles. We are the only in industry that can state our axles are polished by a computer controlled machine. Ktis come with your choice of axle polish level from 3K-100K polish from straight to bent axles. pinewoodderbyspeedaxles.com for more info on our axles.
5. Lift one wheel - 9% increase in speed. You can choose to do this with either a 1.5 or 2.5 bent axle. Or you can choose to have your body drilled for a high wheel. Our standard is steer left with left wheel high.
Basically, you eliminate one less wheel to tell you how to do things. 3 cooks in the pot are better than four for sure. 3-wheel racing is industry standard for all adult racing leagues.
3 wheel racing is the only way to race. Please take note that all bodies are standard 4 wheel racers, unless you choose the option to have it made into a 3 wheel racer.
6. Graphite / lube - Do we ever know this! Derby Dust dry lube is a pure graphite with proper flake size and moisture content that will give you a smooth friction-less surface when you follow their break-in process. Also use the 3-stage wheel polish kit to remove all manufacturing flaws and microscopic burrs from the inner bore. Spin times are insanely stupid.
7. Other (long wheel base, car shape, wheel gap, etc.) 11% increase. I think this is a "Chaos" category. We think these things will make them faster, but really have no concrete data to show it.
I can get a standard wheelbase to run just as fast or faster than a long wheel base. A longer wheelbase is a little easier to tune. We offer cars in all wheelbase lengths to appeal to those that do believe in the hype.
Car shape is important, but COG is the key which was addressed at the beginning.
Wheel gap is important based on the type of wheel hub. It will differ from wheel type to wheel type.
Author's Addition to Science behind a fast Pinewood Derby Car
8. Our conclusion which was not even addressed. Fastest car is a tuned car. Regardless of any other option. Focus mainly on tuning or adjusting your axles. You want your car to go down the track as straight as it can without going side to side.
That is what our kit is about. Not perfect wood grain, not 50 coats of paint that we know a 10-year-old CAN'T do. We stress the importance of tune, test, lube. Tune, test, lube. Proof of a winner is there. I have not heard of anyone that put the time into doing this, lost. 4 years as Derby Dust, never not once. 10 years of building cars, not once.
And every cubber that has come to our shop here in SA has tuned his own car under guidance. Each one of them have never lost a race. And the cars were not perfect, were not tungsten weighted. It can be done even at the 10-year-old level! Not rocket science, just time, simple principles, and the right tools.