Best rear brakes w/ ls1 fronts and bleeding problem

i was running a v6 with drum brakes out back and ls1 brakes up front and it was increadible how well the car stopped but since the engine swap it doesn't stop so good with the added weight and i still have the drum brakes. What would be the best upgrade from the drum brakes?

Antoher thing, i had to pull the front and rear brake lines off the abs unit to do the swap and now my pedal doesn't seem to have the travel it used to. We bleed from the pass rear, driver rear, pass front, and then the driver front which i believe is the correct way to do it. We got all the air out of the lines but something is still not right. With the pedal to the stop the car will squeek forward at stoplights in gear, the brakes barely work at low speeds but if i have to slam them on from say 50 mph they seem to work but it is like an all or nothing scenario. Any ideas here?

You need to bleed the ABS unit (2 screws I'm told)--and do it before you bleed the 4 wheels. I recall the shop manual details this.

Regarding your rear brakes--If you look around, you might find a complete rear (w/brakes) from an LT1 or LS1 donar car. Check out ebay or the forsale section here.

-Rob