Vortec heads? If so, self-aligning rockers? If yes to vortec, and no to self-aligning rockers, that's what you need.
At the very least say what engine it is, any modifications, enhancements, or lack thereof. We need more info, and pics dang it, post up pics of the offending problem
These are the exact engine specs for this
Engine Specifications:
• HP: 330
• TQ: 380
• Block: OE block 4 bolt main 1pc seal 1987-2000
• Bore/Stroke: 4.040 x 3.480
• Displacement: 350
• Crankshaft: OE Reground external balance rear of crank/internal balance front of the crank
• Rods: OE powder metal 5.7”
• Pistons: Hypereutectic 9.1:1 compression
• Rings: Moly
• Camshaft: Hyd. flat tappet
• Cam Specs: 224/234 @50 .465in/.488ex 112LSA
• Timing Chain: Double roller
• Cylinder Heads: ATK cast iron 76cc/165cc 1.94/1.50
• Rocker Arms: Stamped steel 1.5 ratio
• Oil Pan: Rear sump 5qt (not for Chevelles with steering behind crossmember, some corvettes and 62-67 chevy II’s)
• Oil Pump: Melling high volume
• Balancer: Internal balance 8”
• Flexplate/Flywheel: Pioneer #FRA-159 external balance 168 tooth
• Intake Manifold: ATK dual plane intake
• Distributor: HEI (Iron gear)
• Water Pump: OE long pump
• Carburetor: Quick Fuel 670CFM vacuum secondaries with electric choke
• Fuel Pump: Mechanical
• Spark Plugs: Champion #RV12C
• Spark Plug Wires: 8mm
Engine Info:
• Oil: Conventional / Non Synthetic 10W30 with Comp Cam zinc additive #159 for first 3000 miles
• Oil Filter: Wix or K&N per application
• Timing: 34-36 Degrees
• Spark Plug Gap: .035”
• Firing Order: 18436572
• Octane: 91+
• Stall Converter: 2200-2500
• Exhaust: 1 5/8 Headers