I have the Rev-N-Nator on my street driven 70 Charger now for many years with no issues. I have seen none of the more horsepower or starts easier claims as they claim since my car always fires right up anyway but I do like the rev limiter feature just in case I ever over rev it.

1963 Belvedere 440 Max Wedge Tribute
1970 Charger R/T S.E. 440 Six Pack
1970 Challenger R/T, 528 Hemi
1970 Charger 500 S.E. 440 4 BBL
1970 Plymouth Road Runner 383
1974 Chrysler New Yorker 440
1996 2500 RAM 488 V-10 4X4
2004 3500 Dually Cummins 4x4
2012 Challenger R/T Classic.