Can you replace a Dodge 360 with a Dodge 318 motor?

Answer 1

Because these engines are so similar, this swap is generally considered an easy swap. However there are some very important differences that you should know.

But first, the things that are the same; You can use the same transmission/bell housing, rubber motor isolators, and all accessory brackets such as the AC, and alternator mounts. Also, you can use the same exhaust system and exhaust manifolds or headers. Many other items are interchangeable as well, such as the intake manifolds, water pump, distributor, ect. Note, the 360 and 318 used different sizes of 2-barrel carbs so the manifolds are different as well, thus, do not use a 318 2-barrel intake on a 360 because the small 2-barrel carb must be used and power will suffer.

In Dodges, the truck/van oil pan is very different from the car version. The car pan holds 5 quarts and the truck small block pan holds 6 quarts. Also, a 318 oil pan cannot be used on a 360 or vice versa. The 318's and 360's also do not share the same steel motor mount brackets.

Probably the most important difference between 360's and 318's is that 360's are EXTERNALLY balanced and 318's are INTERNALLY balanced. This means that the 360 has extra balancing weight on BOTH the harmonic balancer and the torque converter/flywheel. You must use the correct parts here or the truck will vibrate itself to pieces.

This is getting to be a very popular swap. The information here can be used to swap from any small block (318, 340, 360), or even a slant six, to a Mopar big block elephant motor torque monster, this includes all non-Hemi engines, specifically the 361, 383, 400, 413, 426W, and the king 440. The 361, 413 and 426W are generally very old and are rare, so most swaps use either the 383, 400 or 440.

To swap from a small block to a big block requires a significant financial commitment. This is because nearly everything connected the engine is different. The big change is the transmission. The big blocks do not share a common bell-housing with their small block counter-parts. Therefore, if you have an automatic transmission, you must get a big block transmission or just the big block transmission case. Since both the small block transmission and big block transmission are both A-727, the internals are completely interchangeable if you so desire. Don't forget to get the big block kick-down linkages too!