Monday, December 28, 2009

Setup Sheets, Part 1

I'm kinda excited about this multi-part series, since it's a bit of a departure from recent posts. We're going to review setup sheets in fairly complete detail, so this isn't your usual short-attention-span blog post. You'll be able to download PDF samples and working Excel spreadsheets from Scribd. Here we go...

What is a setup sheet, anyway?

In simple terms, it is a document that details the configuration and adjustment of a race car.

And what is it used for?

  • Define all the setup adjustments, like alignment, ride height, etc.
  • Specify commonly swapped parts, like springs, gear ratios, anti-roll bars, etc.
  • Document the car setup, for later reference
  • Possibly, link to analysis or simulation software to provide vehicle dynamics details
Let's talk first about general content. Future posts will cover how to actually use a setup sheet, communication issues, options for layouts, computing tools and storage, some recommendations, and more.

The simplest setup sheets are handwritten onto a basic blank form. In this guise, it is mainly a working document for crew adjustments to the car on the setup pad. It probably has no more than the following content, and maybe less, depending on what items may be non-adjustable, non-changeable, or non-existent on a specific car:

  • Ride heights
  • Spring rates
  • Anti-roll bar sizes and adjustments
  • Shock adjustments and gas pressures
  • Camber, caster, and toe settings
  • Aero adjustments, such as angles and dimensions
  • Corner weights and percentages

Here's the catch. If the setup sheet is to be a complete and unambiguous definition of how the car is configured, there is inevitably more information required. Sometimes, lots more. The possible list is endless, but here are some common items, in no particular order:

  • Bump rubber spec and packer gaps
  • Third spring and damper components and adjustments
  • Optional aero components and how they are installed or adjusted
  • Cooling configuration, both components and blanking
  • Gear ratios and differential setup
  • Optional suspension geometry and components
  • Brake components, pad/rotor material, master cylinders, bias setup
  • Multiple ride heights - aero components vs. structural/suspension
  • Specific assembly instructions - part numbers, shims, etc.
  • Tire sizes, compounds, and constructions
  • Tire pressures for both the setup pad and the grid
  • Driver weight and fuel load for the setup pad, starting fuel load for the track
  • Shock build spec
  • Part numbers or serial numbers for specific components and assemblies
  • Spring and/or pushrod installed length. Rocker ratio and position.
  • Ballast weight, configuration, position

This can get out of hand. Still, we absolutely have to be able to completely and unambiguously define how the car is expected to be configured when it rolls onto the track. At some time in the future, we need to be able to completely and unambiguously recall that configuration by reviewing the setup sheet.

Taking things a step further, there are two additional types of information that sometimes show up on setup sheets. They are specific component serial numbers, for use in part lifing, and vehicle dynamics calculations, such as wheel rates. I personally choose not to include these on my setup sheets. They aren't essential to defining the car configuration and clutter up its use by the crew. If needed, I think they should be on a separate document, or an "engineer's version" that can be separately printed.

We have to remember that a race car is always changing, and we race or test it as a snapshot in time. Some of these evolving changes are permanent, some not. They rarely seem to fit the existing format for the setup sheet. We have to decide whether, when, and how to indicate these changes on the setup sheet. I tend to mention permanent modifications in the comments section at the time they first appear, then delete them on future sheets - a solution I'll admit to being imperfect.

Sharp readers will have noticed no mention so far of engine configuration and tuning, nor of configuration options and file names for ECUs, data acquisition, traction control, no-lift shift, ABS, or any other electronic systems. Engines tend to be assembled, tuned, and maintained by a separate group which may or may not be part of the team. The electronics are typically maintained and tuned by one or more specialists, a process that can be a bit undisciplined, if nonetheless superbly executed. In an oddity of how things have evolved, the setup sheet is typically the configuration for the rest of the car.

One possible solution to some of these concerns is a "build sheet", produced either as a separate document or as a different print option, similar to what we've discussed for components and engineering data. It can include all sorts of information, like serial numbers, part numbers, modifications, file names, and so on.

So, here's my recommendation:

Use a comprehensive setup sheet that defines everything adjustable or changeable on the race car. Permanent modifications are either excluded or get a mention in the notes section at the time they are done. If it's appropriate for your situation, create a separate build sheet, either to define the car more fully or for part serial numbers. Keep engineering calcs off the main sheet. A worksheet accompanies the car to the setup pad for note-taking during the setup process.

To give you something to think about until the next post, here's a recent sports car racing prototype setup sheet. This sheet is fairly comprehensive, yet this car lacks certain suspension geometry and aero options that I've had on other recent setups. Numbers and other fields, of course, are changed to disguise the real setup. Fields calculated internally by the setup sheet show in blue. If you purchase the full XLS, you'll see the non-printing calcs for ride heights and gears.

PDF - Print or Free Download XLS - Purchase Download

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