Mph x gear ratio ÷ tire diameter ÷ .002975 = rpm. My truck... 60 mph x 3.9 gear ÷ 28.7 diam ÷ .002975 = 2740 rpm. Confirmed by my dwell tach.
Last edited by Jethro in Va; 09/10/202311:07 AM. Reason: Add
~~ Jethro 1954 3100 Back to Life In the Dity Gallery 1951 3100 (gone) / 1956 4400 (still in the neighborhood) / 1957 6400 with dump body (retired) / 1959 3100 panel (in the woods junked) / 1978 Custom Deluxe K10 / 1993 S-10 4.3 / 2004 Chevy Crew Cab / 1945 John Deere H / 1952 John Deere B / 1966 John Deere 2510 / 1967 John Deere 1020
