In practical terms, yes—these two figures describe roughly the same engine size, just measured in different units. A 5.7-liter V8 is typically around 347–348 cubic inches, and many engines marketed as "350" share that exact displacement. However, the exact CID can vary by engine family, bore and stroke, and rounding in marketing materials.
What the numbers mean
Two common ways to express engine displacement sit side by side in automotive conversations. Here's how they relate.
Unit conversion and rounding
One liter equals about 61.0237 cubic inches. Multiply by 5.7 and you get roughly 347.8 cubic inches. The traditional "350" label is a rounded approximation that marketers and enthusiasts use when the actual displacement sits in the high 340s to 350 CID range.
Engine families and tolerance
Different engine families (GM's Chevy small-block, GM's LS family, Mopar's Hemi) use the same 5.7 L designation but with different bore and stroke, resulting in slightly different exact displacements. Some engines are cited as 346 or 345 CID; others are marketed as 350 CID depending on the measurement method and generation.
Practical implications
For owners and buyers, the distinction matters mainly for parts compatibility, restoration accuracy, and official specifications. If you need exact numbers for a rebuild or a parts match, check the engine stamping, build sheet, or factory documentation rather than relying on the 5.7 L vs. 350 label alone.
What to look for when shopping or restoring
Before listing the checks below, note that precise displacement can be confirmed with a quick reference to the engine’s stamped CID and build sheet.
Here are practical checks to verify displacement when comparing 5.7 L and 350 CID engines:
- Check the engine block stamp and VIN/build sheet for the exact displacement (e.g., 350, 346, or 345 CID).
- Be aware that a 5.7 L label may refer to the overall capacity, while the CID can vary by bore/stroke across generations.
- Factor in the engine family (Chevy small-block vs. LS-based 5.7 L) to anticipate parts compatibility.
- Consult official specs or trusted catalogs for your specific year/model to avoid mismatches.
Concluding: In everyday conversation, a 5.7 L and a 350 CID engine are treated as the same family of displacement. The exact number can vary slightly, but the two designations describe broadly the same size V8 in modern GM and Mopar lineups.
Examples by brand and generation
Different automakers and generations used the 5.7 L label to mean slightly different exact displacements. Here are representative patterns you’ll encounter in the wild.
- GM/Chevrolet small-blocks: 5.7 L commonly marketed as 350 CID, though some later iterations are cited around 346–349 CID depending on bore/stroke and generation (Gen I vs LS family).
- Mopar Hemi: 5.7 L Hemi is typically listed around 345–346 CID; it's a distinct architecture from GM's small-block but shares the same nominal displacement figure.
- GM LS-based 5.7 L engines: Often marketed as 5.7 L with a CID around 346–347 CID in practice; exact figure varies with model and year.
Summary: The key point is that 5.7 L and 350 CID describe a similar order of displacement, with exact CID varying. When precision matters—parts compatibility, rebuild specs—verify the actual displacement from stamping/build sheet.