I'm looking for opinions on what battery's to buy I am getting tired of using AC delco they seem to go bad every year. I'm currently using group 24 deep cycle delco battery's for a twin 454 set up. also running a 600 watt amp for my stereo off 1 battery. would the optima battery's be the best choice.

Starting engines off of a deep cycle battery will kill the battery. They are not designed for starting. I would install a 2 battery system with a starting battery and a deep cycle for running of accesories.

There are numerous resourses for the best way to accomplish what you need.

I agree with the last post. I have 2 batteries, one to start and the other to run. I have a third battery to run my stereo system - that battery is an Optima.

Most deep cycles die an early death simply due to undercharging. They take much longer to fully charge than starting batteries. If you typically boat for short periods and don't recharge with shore power, use a dedicated starting battery. For accessories use a deep cycle. The deep cycles will die early however without proper recharging.

It's odd that you have only one battery for two engines. At least that's the way I read it.
My 20' Formula came with two batteries for one engine. A starting batt plus a deep cycle for the rest of the circuit.

Batteries???
I decided to go with a lesser priced battery. If it dies in a season I'll return it for a new one. I'm tired of paying high prices on products.

How did you set that up, i currently have 2 batteries in my 357 formula, but im thinking of adding a 3rd for the stereo, how would i wire it, and would i have to worry about my alt?