i wanna know more bout slant sixes

i havnt actualy heard of the 3.8 was it an amc?the 4.0 has more hp and torque than the 4.2 but it makes the most torque at maybe im wrong but i think its like 2400 to 2600 rpms its also fuel injected the 4.2 had a carb so there is part of the difference in gas milage they both share the same block when my first motor got finished off i seriously considered the 4.0 or a 360 :toothy5: but i got my new 4.2 that had a weber carb and a cam(i dont know what kind) for a hundred bucks i just couldnt let that deal go by so i got the older gas hog lol also i got 2.73s for gears it is what was in it and i just havnt got new ones yet