I had a friend look into this for a 440 BBChr pickup truck, but he bought a turbo instead.
Now I'm looking at the swap for my 72 duster (408cid, 727 11" Breakaway, 2.76 gears - 12.70s@107 on 235x15 ET Streets, about 3,000rpm on the highway at 80mph.)
I hope some real experts chime in, but here's what I know so far:
- It's @!#$% expensive
- You will get flamed alive by the brand loyalty guys
- If you like EFI maps, you'll love this - fully programmable & techno geek heaven. make it as angry or soft as you want, wherever you want just by typing it in.
- you need some SERIOUS upgrades for it to live but when built, 4L60E's been reliable behind 11 sec motors. most OEM issues were from towing heavy loads in overdrive/lockup and smoking the lockup clutch. need to upgrade to 5 gear planet carrier, and I think a steel sun shell or else big block torque will kill it. Race clutches are a good idea, valve body mods too.
- At a min, you need the puter & harness, flywheel housing & adapters, a converter, a core trans, and a modified crossmember
- main decision is whether to buy a complete kit, or buy the pile of parts and upgrade the trans yourself. Kiesler has all the swap conversion parts (and complete kits). Raptor makes all kinds of trans upgrade goodies, and Yank makes really great converters.
- DIY can save you ~$2000 but you need access to a couple special tools, and you need to know what WTF you're doing. Watch a 700R4 rebuild video to see basically what's involved. not *hard* but more complicated than a 727, and a very tedious job.