This Comp Cams 35-235-3 SBF 351W X4254H Xtreme 4x4 Hydraulic Flat Tappet Camshaft fits the 351W Small Block Ford from 1969-1996. Comp designed this cam for performance street/strip use, and it features a good torque for 4x4 and excellent mid-range power. It is great for RV or towing A 9.0:1 or higher compression ratio and a 1600+ stall speed torque converter are highly recommended. Comp Cams 35-235-3 SBF 351W X4254H Xtreme 4x4 Hydraulic Flat Tappet Camshaft Specs: For the 351W Small Block Ford engine from 1969-1996 Stock (O.E.) valve springs can NOT be used. Basic RPM Range: 1200 to 5200 Valve Lift Intake: .477 Valve Lift Exhaust: .493 Advertised Intake Duration: 254 Advertised Exhaust Duration: 262 Intake Duration at .050”: 210 Exhaust Duration at .050”: 218 Lobe Separation: 111 Intake Centerline: 107 Firing Order: 1-3-7-2-6-5-4-8 Made in the USA Comp Cams designed this Hydraulic Flat Tappet camshaft for high performance on the street and drag strip. Comp Cams –The Absolute Leader In Valve Train Technology!