The most important thing to state when asking for a cam recommendation is to describe EXACTLY what you expect from the car, and what you are willing to live with. The biggest mistake most guys make is to over cam an engine. A bigger cam holds the valves open longer so the engine can breathe at higher RPM where it can make more horse power. A bigger cam increases overlap, the period when both valves are open at the same time. More overlap decreases engine vacuum and makes for a rougher idle. A bigger cam pushes the power range of the engine up, you lose some low end for bigger gains up top. You can actually make the car slower "real world" by over camming an engine. It may sound great at idle, but be a pig on the street in typical driving. There is no such thing as a 2000 RPM converter, or any other number for that matter. Buying an off the shelf converter thinking you'll know where it will stall is a gamble. Having a converter built for your car/engine cost more, but you get what you pay for when it comes to torque converters. Stall speed depends on many factors including engine torque, car weight, and gearing, among other things. You also should consider static compression ratio when choosing a cam. The engine does not run at the static compression ratio. Cam timing affects things. The intake valve is open as the piston comes up on the compression stroke. No compression can build until the intake valve closes. Different cams close the intake valve earlier or later. That is why you will see a static compression ratio requirement in a cam description. The running compression of an engine (Dynamic Compression Ratio DCR) determines how it will perform in an engine and whether it will run on pump gas. For more on DCR, read this, http://www.empirenet.com/pkelley2/DynamicCR.html
The 1971 455 will have 8.5:1 compression or less. Stay smaller on the cam, bigger is not always better.
Larry
1970 GS455 Stage1 Race weight 4025 lbs.
TSP 470, 602 HP, 589 TQ
MT headers, Gear Vendors Overdrive
Best E.T. 11.54 Best MPH, 116.06
1998 Riviera SC3800
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