Help convince me to go BB in my Duster?

So, I have a '74 Duster, who through a friend of a friend, can get a pretty solid 318, which would get built to 300-350, which would of been fine, but now I think it wouldn't be as enjoyable, or I'd always want faster?

I was looking into a 440 swap but everyone I know is telling me that it won't work, too much fabrication, front end will sag. Also is this too adventurous for a first-time motor swap? (i'd probably try to find one one CL that comes with trans, motor, msd, etc etc)

What all do I need for going BB?

I know through just common sense, I would need at least an 8 1/4 rear end, and from watching that one episode of Roadkill, I know I'll have some problems with the headers.

Is there a lot of fabrication into bracing the front end? Or would it just be heavy duty torsion bars? Do I need to mess with the trans tunnel?

My checklist so far (regardless of BB or SB):
- Schumacher Motor Mounts
- Heavy Duty Torsion Bars
- 8 1/4 rear end
- Some fabrication for the Headers
- MSD or some other ecu?
- disc brake conversion


Thanks for the help guys!


I'd upgrade to the 8.75 rear, with a sure grip or other locker. And some Caltracs or super stock springs. otherwise, looks good.


and as far as convincing goes....

No Replacement for Displacement. Machining and parts for the most part almost the same regardless of 318 or 440, sometimes the 440 parts are cheaper, sometimes the 318 parts are cheaper, but in the end, you either have a 318 maxed out or a 440 that probably isn't.....and that has a heck of a lot more torque.