1977 904 horsepower limits?

So in other words to give you the best bang for the buck $2500 to make it a better setup. About $1800 to build up the trans and use your stock converter and have the stall increased. $1500 to just make the trans a little stouter. This is just from my experience estimated prices from having a local trans guy doing the work. Some of these online trans businesses like monster or any other big name guys can build to order and are good quality but they can be a bit more pricey from my experience. The guy I use is is just a local yocal but if I want something built new I use trans king in Conroe TX
maybe depends on where you are. Here, just a "bench job rebuild" is about 400 - 450 without converter. I just paid 650 out the door for a rebuild on a 727 with new converter out of a 4x4. I paid 750 for 904 with some upgrades to strengthen it like kelvalar bands and some things to make it stronger - without converter.