Charging system troubleshooting

This one is on Mancini's website and they seem to contradict themselves. On one hand it states for drag racing use only, but the sentence below says it works on all stock ignition systems, no modification needed. I'm calling them.
i had 2 street cars i used them on, worked fine. these were nice for the conversion since they have the plug and play hook ups for the old style VR built in