$31 8427 4L80 shift tables...definitive answer

[V8Astro]

I've been successfully modifying my tables for shift firmness. I'm still not sure which table is the "best" for increasing shift firmness. Is it the force motor table or the line pressure adders?

[lionelhutz]

Either one can work, but I'd stick with the line pressure adders if you're just going for better part-thottle shifting. Do remember that once you get to "96" you can't get any more pressure with that table.

If you drop the force motor current in the 96 column then that should equal a higher maximum pressure. Blend the rest of that table down to meet the new 96 column and pressures will increase everywhere.

It'd certainly be a good idea to use a gauge when changing the force motor table. I'd think you'd want to stay under about 230psi pressure.