[2manyT/A'S]

I have several 78 W72 4 speed T/A's that are reasonably low mileage & basically STOCK,other than true dual exhaust (2 1/4") with set up carbs & HEI's and am VERY happy with MY butt dyno readings.....(78 W72 sticks came with 3:42's)

They DO pull pretty HARD & run GOOD but obviously the stock camshaft is holding them back.

You can probably bump your initial to 19.

Did you check for timing chain slop?

Is your stock EFE valve in place still? (and working?)