had a Dart with a 68 340,headers,484 DC cam,LD-340 with 3310,3.23 gears and 4-spd. car ran 13.18 @108 with 7 X 27" cheater slicks.I could not shift, never used 4th gear, valve guides were sloppy because the heads had been surfaced and I never checked clearances. SO, now, I would like to...