a 440 weighs quite a bit more than a stock 360. 670 lbs for the 440, 550 for the 360. Stock for stock of course. Powerwise, yeah, the low compression 440s aren't hot shots by any means but are stout enough. especially if youre car is weakened by rusted out floors or whatever. Will your's twist? who knows. I'm not Steve Dulcich, he knows way more than me, but I'll say this, have someone jack up a corner of your duster with a floorjack as you watch the door gaps closely, I'd bet you're gonna see the flex in these things just from that.