I’ll give this a try today. Thank you!This could be as simple as the transmission is shifting too soon. Take the car out and pull in down to 1st gear. Run it up to 4500 rpm or so and shift into 2nd. With the 3xxx converter you will stay in the power band and she should keep pulling until your shorts are dirty. Any 340 I have had really liked rpm and if you can't get it to 4500 you definitely have some problems to work out.
Good luck, Jerry