This is my first oil change with this boat and I'm wondering how much oil the 1990 454 mag engine stock holds. I'm just trying to make one trip to the store and dont quite trust my local marina because they were wrong before on the last boat I owned. Thanks in advance.

My 94 454 mags with oil fiter mounted up top takes 7 quarts. If you have the filter up top, poke a hole in it to let the oil drain down, much less mess...