Hydraulic Roller - Big Mutha' Thumpr: Street/strip, needs 9.5:1 compression, 2800+ stall, intake, gears and headers, very rough idle.; 299/319 Advertised Duration, 243/257 Duration .050", .533"/.519" Lift, 107 Lobe Separation; 2500 to 6200 RPM range; Must use bronze tip fuel pump pushrod when using high pressure or high volume pump;
