Hydraulic Roller - Xtreme Fuel Injection (XFI): Superb low end and mid-range for 350 tuned port injections. Requires custom tuning.; 260/270 Advertised Duration, 210/218 Duration .050", .560"/.555" Lift, 113 Lobe Separation; 1200 to 5200 RPM range; Recommended use with 1.6 rocker arm ratio; Must use bronze tip fuel pump pushrod when using high pressure or high volume pump
