318 vs. 360?
The 318 is a very good engine and can be made to move. GoodysGotACuda is proof of that. But the same performance principle's and $'s applied from a 318 to a 360 will get you more power and driveability.
FYI...(I'm sure you're already aware of this, but just in case) The 400 you have may be a big block and parts will not interchange with 318 and 360.
BTW - I have the burnout of the black Charger too. It's one of the best one's I've seen on video or live. :thumbup: