Hydraulic Roller - Xtreme Energy: Good for Pro Street and bracket racing. Needs 10.5:1+ compression, 3500+ stall, very good intake, headers with low gears.; 300/306 Advertised Duration, 248/254 Duration .050", .560"/.580" Lift, 110 Lobe Separation; Adjustable valve train required; Must use bronze tip fuel pump pushrod when using high pressure or high volume pump;
