What if my main clearances are out of spec?
Documented on the Chevrolet Small Block 350 (sbc 350) build
Published March 28, 2026
If clearances are too tight or too loose, you can change to a different bearing thickness (undersize or oversize shells where applicable) or machine journals/replace bearings as required.
Full Answer
If clearances are too tight or too loose, you can change to a different bearing thickness (undersize or oversize shells where applicable) or machine journals/replace bearings as required. Excessive out-of-spec clearances may require machining the crank or selecting alternate bearings.
Documented In This Build
Related Knowledge
Why do you file piston rings instead of buying pre-gapped rings?How much end gap should I aim for on a SBC 350?How much material should I remove when filing a ring?Is plastigauge accurate enough for checking main clearances?How important is degreeing the cam?What torque sequence and values should I use for SBC heads?How do I set lifter preload or hydraulic lash?What should I do to prepare the engine for first start and break-in?
Related Parts
Assembly lube
$15
Main bearing set
$60
Piston ring set
$120
Plastigauge (assorted)
$8
Related Tools
Torque wrench
Engine stand
Feeler gauges
Ring filer / hand file
Micrometer / inside micrometer
Plastigauge
Ring compressor
Related Videos
Small Block Chevy 350 Build Pt. 6 | This Is How It's Actually Supposed To Be Done
Small Block Chevy 350 Build Pt.5 | Continued frustrations with rod clearances
Small Block Chevy 350 Build Pt. 11 | Installing the intake manifold and figuring out sbc nuisances
Small Block Chevy 350 Build Pt. 7 | Checking Crank Clearance and installing the rods.
Small Block Chevy 350 Build Pt. 8 | Installing Camshaft and timing components
Small Block Chevy 350 Build Pt.1 | Lifting This Engine Without Breaking It