This section contains editorial comments. I hadn't planned on having it, because I wanted to keep this page mostly free of opinions. However, now I feel the need to include it. Some results may not apply to your race environment. However, this test was run on my track, and I'll bet you dollars to donuts that your track is not exactly the same.
Some tracks have constant slope.
Some tracks are S-shaped. Some tracks have a constant slope drop, then a short transition, then the flat. On any of these tracks, and perhaps others, be warned that back-weighting may be the wrong choice. The stability gained from center-weighting might give you a faster car. Don't let the close calls dictate your actions.