Trust me on this one, I do this all the time.

1/4-32 National extra fine series. (or Unified Thread Standard)
Drill 7/32" (0.2188") then tap.
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1/4-28 National fine series.
Drill #3 (0.2130") then tap.
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1/4-20 National coarse series.
Drill #7 (0.2010") then tap. (13/64 is acceptable, but a slightly looser fit. not class 2).

http://www.physics.ncsu.edu/pearl/Tap_Drill_Chart.html

1993 Daytona, 5.50 at 130mph (1/8) 1.19 sixty ft (PG). Link to 572 B1 - Part 1