Mine is not a C series.. but a 77 Chevy H70.. with a 6V53, Spicer 5252A short 4th... working 5th. -n- 2 speed ..... tops out around 60 in a hurry.. at an ear ringing 2925 Rpm's..
I just want a more user hearing friendly top speed and RPM option.. and like for it run 65-70..
