Junkyard Engine Spotter's Guide

Mopar B and RB
Low-deck B engines (361s, 383s, and 400s) can be easily distinguished from raised-deck RB engines (413s, 426s, and 440s) by the location of the engine identification pad. On B engines, the pad, which is stamped with the engine displacement, is located on the passenger side of the block just below the distributor (A). The ID pad on RB engines is located at the front of the engine above the water pump housing (B) and may be obscured if an AC compressor is mounted.

Both ID pads include a stamped single-letter date code (starting with the letter A for 1965, B for 1966, etc.) and the displacement. A letter E stamped after the displacement indicates the engine has a cast crank.

Mopar LA Engines
Externally, small-block Chryslers all basically look the same, but they're easy to identify because the factory stamped them with an ID code on the front of the block just below the cylinder head on the driver side. The code is a series of numbers that indicate production location and date, as well as displacement. (Note: some 273s are stamped only "27".) Many 318s and most 340s and 360s also have the displacement cast as the last three digits of the casting number on the side of the block.

An easy way to spot a late externally balanced 340 or any 360 is to look for a balance weight on the harmonic balancer (right). You can differentiate 340s and 360s by the displacement cast as part of the casting number.

Mopar Poly 318
Produced from 1957 to 1966, the Polyspheric 318 shares the same displacement as its later and more popular kin (but not much else), and it's probably best avoided. You can easily spot one by its scalloped valve covers.

By Matthew King

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