What about with a 700R4 trans.?

Question

Would that gain more housepower then stock on a 1977 Sliverado?

Answer 1

transmission won't do a thing to add to Horsepower. it may change the shift points a Small bit but not enough to make much difference.

Answer 2

No HP gain,but you will get better MPG.

Answer 3

If you have a turbo 350 or 400 in your truck now, the trans you have is actually stronger than the 700R4. The 700 R4 is an overdrive, which will give you extra gearing to decrease your speed to RPM ratio. The best thing  is to leave stock and change the torque converter.