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Discussion Starter #1
I measured as everyone suggested to get the cam lift. I am getting a .300 rise on the lobes. Since i am having a hard time believing the cam is a .300 lift I must be doing something wrong. The cam is from a 390 motor...
 

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Multiply that by the rocker arm ratio to get the total at the valve. If you're looking to measure duration, keep in mind most Manufacturers, but not all, quote duration between 0.050 lift (at the valve).
 

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Using crane's rocker ratio suggestion and the .300 lobe seems to indicate .528 lift.....sounds reasonable.
 

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Ford used two stock rocker arm ratios for the FE. The adjustable rockers were 1.76 and the non-adjustable 1.73.

None of the stock FE cams had more than .298 lift (at the lifter) on the intake or exhaust.

This is all according to Tom Monroe's book on the big block Ford.

If you're getting an accurate reading, you've probably got an aftermarket cam or if it's original to the engine, maybe something special.
 

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Discussion Starter #5
I am sure its a aftermarket cam, I just didn't know the lift, I will contact the person I bought the block from and find out what it is...I appreciate the response..
 
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