Elgin E-293S

http://catalog.elginind.com/elgin/

It's an exact copy of the original 261 solid lifter cam, the one that was also used in 6-cylinder Corvette 235's. Elgin used an OEM Corvette cam as a pattern, and the only difference I've been able to find is a slight change in the clearance specification. Elgin lists it as having a "290 degree" duration, but they're also including the clearance ramps in that figure. The actual "valve open" duration is around 260-something which gives the engine a good idle and slightly better torque and horsepower than a stock 235 cam. Elgin does not sell direct, but they will provide you with a list of their vendors. I buy mine from the "Internal Engine Parts Warehouse" system, specifically, Nashville Engine Parts in Nashville Tennessee. IEP has facilities throughout the southeastern USA that deal with professional shops and parts stores, not hobbyiststs and DIY'ers.
Jerry

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