71 Dodge Dart Swinger in England

Actually the 360 mains bearings, crank diameter is smaller than a 318/340, and allpar is incorrect stating all small blocks installed in A bodies had a 90° oil filter adaptor. Only the small blocks with high performance exhaust manifolds in A bodies had this adaptor for clearance with the RH exhaust manifold. If allpar was correct id be sitting on a goldmine in cast iron A body filter adaptors, as my local boneyard is littered w A body V8 cars. My 74 parts dart came w a 318 2bbl and no filter adaptor. Not needed. One off a chrysler fifth ave is aluminum, and more readily available. Got mine for $10 off an 89 fury lll

However i was remiss on the forged VS cast crank as i was only talking about the basic dimensional architecture of the engines themselves, and not the metallurgy, so in this regard you are correct about the 340s forged internals.

However when the LA (Light A engine) series small block was designed and produced as a 273 in 1964 all of them came with forged cranks, most with cast rods except for i believe the commando/charger engines. Later on came the 318. I believe these continued on with forged cranks and cast rods through 1973, and in 1974 went to cast cranks and forged rods. Though i dont know why the switch was made. It must be noted a 273 steel crank will fit a 318/340 as the main journals and rod journals are the same. All rods are dimensionally the same on all LA engines, with the 360 having a longer stroke crankshaft.

If your is a 360, it is an externally balanced engine like a chevy 400, and 454. This means there is an external balance weight on your torque converter and a special front damper for the external balance on the 360. Do NOT swap these parts out for 318/340 parts unless you have the crank rebalanced internally. Otherwise the engine will eat itself in short order. As such the torque converter is clocked to the engine flexplate a certain way. If you decide to demate the engine and trans for a rebuild, i recommend making a punchmark on the flexplate and converter at one attach bolt that bolts these 2 together, when it goes back together line these marks back up and bolt it together. All the holes are drilled slightly off so the torque converter lines up with the weight clocked ONLY in the correct position. If you dont do this eith the 2 punchmarks before dissassembly you will chase your tail for hours wondering why half the bolts dont line up no matter what you do.