max valve lift for "92 vortec v6
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RE: max valve lift for "92 vortec v6
Maximum valve lift for Chevrolet 4.3L V6 engines is .525" with 1.5 rocker arms and .560" with 1.6 rocker arms.The engine will be a porch dog with such a cam but it will sound bad at the traffic light so do notaccept any challenges with somthing like that in your engine.The V6 4.3L cylinder heads flowterribly even when ported and flow tested using2.02" I and 1.60" E valves. Theydo not flow as well as the 305 CI SB ChevyV8 heads and the V6 engine isout of breath at 5000 RPM with a 4.10 rear cog. A cam with more than .350" lobe lift or .525" valve lift (1.5:1 rockers), will cause the hydraulic roller lifters to hit thelink bars.
An exhaust system that is too effecientis just as bad as a radical cam or maybe even worse. Large diameter dual exhaust,tubular headers and straight through mufflers on a 4.3L V6 canover-scavenge, or what is commonly known to"blow-down"the combustion chambers, especially with a high-lift, long duration cam that hasexcessiveintake and exhaust valve overlap. That kind of cam and exhsut systemwilldraw the incoming fuel-air mixture out the exhaust pipes during the exhaust valve overlap period. The late Ed Iskendariansaid, "The exhaust valve closing event is the most important" A well timedexhaustvalve closing event traps the incoming fuel-air mixture in the combustion chamber until it is lit and makes power.Overly efficient exhaust flow that pullsthe fuel-air mixture out the exhaust pipe(s) behindthe burned exhaust gasmeans loss of power. A small engine such as a 100 CC dirt bike or a 4.3L V6 Chevy engine needs a lot ofexhaust back pressureto hold the fuel-air mixture in the combustion chamber where it will do mostgood and buildlow end torque. A 4.3L Chevy V6 engine without any low end torque??? Spare me.
Radical, long duration, high lift camshaftsare for high revving, largedisplacement engineswithample carburation or forced induction. That kind of equipmentcan kill the power of a small displacement engine .
An exhaust system that is too effecientis just as bad as a radical cam or maybe even worse. Large diameter dual exhaust,tubular headers and straight through mufflers on a 4.3L V6 canover-scavenge, or what is commonly known to"blow-down"the combustion chambers, especially with a high-lift, long duration cam that hasexcessiveintake and exhaust valve overlap. That kind of cam and exhsut systemwilldraw the incoming fuel-air mixture out the exhaust pipes during the exhaust valve overlap period. The late Ed Iskendariansaid, "The exhaust valve closing event is the most important" A well timedexhaustvalve closing event traps the incoming fuel-air mixture in the combustion chamber until it is lit and makes power.Overly efficient exhaust flow that pullsthe fuel-air mixture out the exhaust pipe(s) behindthe burned exhaust gasmeans loss of power. A small engine such as a 100 CC dirt bike or a 4.3L V6 Chevy engine needs a lot ofexhaust back pressureto hold the fuel-air mixture in the combustion chamber where it will do mostgood and buildlow end torque. A 4.3L Chevy V6 engine without any low end torque??? Spare me.
Radical, long duration, high lift camshaftsare for high revving, largedisplacement engineswithample carburation or forced induction. That kind of equipmentcan kill the power of a small displacement engine .
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