bad times,need help

ive been trying to get my car going for a while. I have a 68 chevelle that ive been working on for a while. I bought a 396 for it ang have been buliding it little by little. I asked a guy i know about what cam i should get for my car and he told me i could use any cam and if I wanted it to lope real good comp cams 305s wood be good. So i listened to him. I purchesed a 3200 stall and 3.90 gear rearend. I am now told by the mechanic that is helping me that the cam is way to big. I dont think i can return it because well i already put it in the motor. will this be a mistake going aahead and running it with that cam. the motor has 10.25:1 compression and i am using hedders and and a performer rpm. this cam will be used maybe every other saturday.

You need to put the cam specs on the page. Otherwise, we cant help.

the lift is .575 and the duration is 253 at .050

575. is a bit much, but it should be drivable as long as you dont need to idle forever. If your going crusing, it should be fine. If your driving Stop and go, change it to something around 500-ish.