t What ever a 383 fit in a 440 will fit too with a slightly tighter exhaust clearance and a bit of carb room due to higher deck, as long as you stay with low air cleaner, otherwise you may need a hole in your hood. I ran into that on an E body I swapped a 440 into with a tall manifold and factory air cleaner from a mid 60's super commando setup. In factory trim the 83 was rated at a higher HP/c.i. than the 40 and torque was higher for the 440 than the 83 in the same manner. If you checked the shop manual ratings you would see that the 83 was pretty much on par with a 360 for TQ. with a slight advantage in HP. However the factory changed its method of rating system between production of the 83 and the 360. The low deck of the 83 required a shorter rod which affected the rod ratio of the late model 83, in the early 60's there was a 383 built on a block with the same deck as the 413,426W, and the venerable 440. there was also a couple of smaller big blocks 350 and 361 inch in low deck starting in 1958. In the tall deck version using the same length rods as all the BIGGER bbm's except for the rod that was used in the even more famous HEMI which is 0.100 longer. These rods have been used in 440 if you remove the pin bushings and fit them to the larger pins of wedge motors and even in custom built 426W's, for whatever reason I have no idea since the general practice is to simply build as big as you can go. By using the Hemi rod in a wedge block you can gain about 1k rpm increase in max due to the changed rod ratio which is more tolerant of higher RPM. I did this once using a set of TRW pistons with a 9:1 comp ratio, no machine work need be done as the piston remains below the deck even with the longer rod. Just be sure to use a .47 gasket if you use closed chamber heads, if using open heads thinner is ok as long as you make sure to bevel the piston so it clears the head. The 440 crank can be installed in a low deck such as a 383 to build more TQ at the expense of safe RPM. Also the use of the 440 crank in the 400 block with correct pistons gets you into the 470 inch range which is using the stock length low deck rods and you get an engine that puts 440 TQ ratings in the dumpster. Of course there is also builds for using 440 blocks with stroker cranks for over 500 inches and you can build engines of fantastic power #'s. So the question becomes why build a 383 when for basically the same cost you can have over 470 inches of power producing engine that looks and measures the same outside as a smaller engine. For the most part, a 440 will power your car maybe 2 seconds faster in a 1/4 mile over a 383 just because it has more torque to make it move off the line and in the first 60 ft or so, but it's a tough call as to which is better. As it goes, there's not much replacement for displacement which is why most people would take the 440 block and built it as big as they can, 511 is about as far as practical without modifying for smaller rod bearings which makes the crank weaker mostly. Anything bigger calls for a different aftermarket block with a raised cam position. Looks like about everyone here has good info... It comes down to what block you have to start working with or can get hands on. 383's were more plentiful and older for the most part. Later 440's seem to have a bit of an edge in the coolant system, passages in the deck but the older engines can be matched to that easy enough. Heads for later engines were not quite what the heads from 67 to 70, maybe late 71, after that they went down hill on emissions, flow reduction and then unleaded fuel was hard on the valve seats. Lots of cracking in the exhausts which made repair and salvage more costly. But new aluminum heads are so awesome why bother with old iron heads. Compare the bore size of the 400 to a 383 and the fact you can use such a bigger intake valve in the 400 block. You will need a K member for the big block though and torsion bars to handle the extra lbs. MOPAR never made a bad engine in any size!
