Bill of Materials
This is a rough cost estimate, both the estimated price and actual cost are subject to change.
We spent a lot of time talking about make or buy decisions in order to limit the scope of our project, and to focus it on parts that we could manufacture. Often the make or buy decision was as simple as “can we even make this”. Other times it involved a few phone calls, some in depth conversation, and a little number crunching.
The resources that we have at our disposal made a lot make or buy decisions for us. Things like axle housings, engines, transmissions, wheels, tires, and brake components require extensive design and testing, as well as large scale casting and precision machining processes to manufacture. In order to put the car together in time and on budget we had no choice but to purchase these components used, for as cheap as possible. Most all of these were then modified to some extent for specific use in the race car; for example: the axles were both trussed and outfitted with brackets and tabs to make them work with our steering and suspensions components. This option was still significantly less expensive then our next alternative which would have been having custom axle housings manufactured to our specs.
Reliability and competitiveness were other important considerations for us when deciding whether or not to manufacture components for the car. Buying a radiator costs money, but losing a race because we chose to manufacture a radiator and failed bares a cost that is hard to quantify, or compare. In the case of components like the various heat exchangers on the car, hydraulic steering components, and suspension dampeners, we chose to buy components that we felt we could trust to stand up to the rigors of racing.
Safety, and regulations were a third consideration when deciding whether or not to manufacture components for the car. In some cases, the rule book dictates that we run sanctioned and approved aftermarket equipment. This is true for the occupant seats and harnesses, Hans device, and other safety components on the car. In other cases, we decided that our safety was better trusted to reputable, experienced, and capable manufacturers. This drove us to purchase components like our bladder fuel cell and brake rotors.
Finally, we had to make decisions over a list of components that we could make, but that were also reasonably available for purchase. On this list were items like our rear trailing arms, suspension, engine and sub-frame bushings, differential covers, body panel tabs, and more. In cases where we had experienced man hours available we chose to use them instead of the budget. This meant that parts like the bushings and trailing arms would be designed and manufactured in house. When all capable man hours were exhausted, the budget stepped in to procure parts like differential covers, and body panel tabs.
All told we are not building quite as much of the final product as we would like, but that’s a compromise, and a choice we made which allowed us to move forward. We still have lots to design, build, and learn, and plenty of room to be creative. In the future, K.C. can work on developing application specific components to replace generic bolt on parts as time and money allows.