Chev SB DomeCylinder Bore: 4.125"Compression Distance: 1.000"Stroke/Rod: 3.480" w/ 6.250" Rod (372ci)Stroke/Rod: 3.500" w/ 6.250" Rod (374ci)Stroke/Rod: 3.750" w/ 6.125" Rod (401ci)Stroke/Rod: 4.000" w/ 6.000" Rod (428ci)Dome Volume: 3cc Comp Ratio: 3.480" Stroke w/64cc Heads: 12.8 Comp Ratio: 3.500" Stroke w/64cc Heads: 11.9Comp Ratio: 3.750" Stroke w/64cc Heads: 12.7Comp Ratio: 4.000" Stroke w/64cc Heads: 13.4