A buddy and myself, have been going back and forth on which is the better option. Price, parts availability, maintenance. I had been leaning towards the 4l80e, but the th400 is looking pretty good too. I'm still piecing together my dragweek car. An overdrive is a must. Not a real heavy car, 3000 lbs plus driver. Small tire and in the neighborhood of 1000 hp na. Which way do y'all recommend?