Mopar's big block V8 engines are divided into the B-series and RB-series — both share a similar architecture but differ in deck height, and they are not interchangeable in most applications.
WHERE TO FIND THE CASTING NUMBER: The block casting number on a Mopar B/RB engine is located on the left side of the block (driver's side), above the oil pan rail. Clean the area thoroughly — this location tends to accumulate oil and grime.
COMMON BIG BLOCK MOPAR CASTING NUMBERS: 2536430: 383 ci (B-series) — found in many Dodge and Plymouth muscle cars and trucks, 1959–1971 2806430: 426 street wedge — the street version of the Chrysler 426, not the Hemi (note: this is the wedge-head 426, not the 426 Hemi which has a completely different casting) 3614230: 440 ci (RB-series) — used in high-performance applications throughout the late 1960s and 1970s; found in Road Runner, Charger, Super Bee, and B-body trucks
B-SERIES VS. RB-SERIES: B-series (low-deck): Includes the 383 and 400 — shorter deck height • 383 and 400 B-series engines use a smaller main journal diameter RB-series (raised-deck): Includes the 413, 426 wedge, and 440 — taller deck height for more displacement • RB-series engines have a larger journal diameter • The taller deck height means RB heads and B heads are not interchangeable without modification
Note: Neither the B-series nor the RB-series is the same as the 426 Hemi — the Hemi uses a completely unique block, heads, and casting numbers.
For help confirming your engine, contact us at 1-844-XPARTS-1 or support@expediaparts.com.
