401 jeep into my dart

just built a 401 for an 81 J10. if youre hell bent on doing it, a chrysler trans AMC case will work, 727 or 904, 290/304/348/360/390/401, but the problem lies in sourcing a flex-plate. 99% of 401's had a TH400 backing them. the only factory application that had a 727/401 combo was a 74 ambassador. remember, 401's balance differently than any other gen II or gen III AMC V8. DO NOT use a 290/304/348/360/390 flex plate without having it balanced to the 401, it will shake like crazy. harmonic balancers are 401 specific also. I ended up having a 360 flex-plate balanced to the 401 rotating assembly, it was cheaper and less time sourcing an original. theres also a torque converter snout centering ring pressed into the back of the crank, similar to a pilot bearing, this MUST BE REMOVED to use a chrysler trans. GM units have a smaller diameter converter snout than a chrysler. cost me a solid day of work, i found that out the hard way. as for weight, these things are HEAVY. waaay heavier than any rip-roaring smallblock you could build, and wider too. Parts, dont even start, manifolds are fairly expensive, and the new front covers through bulltear are an excellent piece, not very cheap, but sanding the oil pump housing to spec is a tedious, extremely boring, and time consuming process. oil pan selection is limited, however the J10 360 pan is a mid-sump, it would probably work with minimal mods. Oh and the dipstick tube MUST be replaced, do not ever re-use one, they will leak and/or snap off right at the block....major nightmare to deal with. these things have issues keeping oil-pump/dizzy drive gears in them. they love to eat them left and right. GET A MATCHED SET. PERIOD. and do every oiling mod you can, it will be worth it!!!!! like running a high pressure line from the o.p. sending unit into the front cover to spray oil directly on the cam/dizzy gears, and getting an 87-91 chrysler modified AMC oil pump base housing, or blocking off the lower bypass in the original AMC units. my biggest beef with these things is the oil pump itself, steel impellers in an aluminum housing....usually too far trashed to re-use the front cover. bad-juju. so anyway, if youre hell bent on doing it, theres an entirely too large list of stuff to remember. :)