Question:

I’m in the process of building a Top Dragster and wanted to know if there are any ignition systems that are not legal”

Answer:

There are two ignition systems that are not legal.  Per the 2018 NHRA Rulebook in General Regulations section 21, page 37, ignition, “The use of any programmable multi-point rev limiter and/or rate-of-acceleration rpm limiter, either by themselves (e.g., MSD 7561) or integrated into the ignition system (e.g., MSD 7531), are prohibited in NHRA competition.”