You betch'a... A pair of Trojan 225's are a favorite with the bass crowd for runnin' and gunnin' all day. Look for the "Reserve Capacity" rating. There's a great "everything you ever wanted to know about batteries" site. I'll try to find it and post the link if someone doesn't find it first.
This wasn't the link I had in mind BUT it has the information you want (and LOTS more).