Cam explanation
Cam explanation
Ive been looking around at cams, but I dont get what the numbers mean. Can someone explain the numbers on the duration and etc. Im willing to sacrifice some idle, but not to much where its still capable of being a daily driver.
Duration is the amount of time the valve is open. it's shown in degrees, relating to degrees of the cams rotation.
Advertised duration is what the cam maker considers the total open time of the valve, and it is usually a higher number than "duration @ .050
Duration @ .050" means the amount of time, in degrees of rotation that the valve is open between ..050 open and .050 closed. Duration @ .050" is the best way to compare cams.
Lift is the peak amount that the valve would be open, in inches.
The higher the lift and duration, the more air can get into the cylinders, thus more power. But, the longer the valves are open, the less vacuum is created, causing idle and low speed driveability issues. It's a comprise between top end power, and low end torque/drivebility.
A good cam, from what I've heard, thatdoesn't have much effect on driveability and idle is the Z06 Cam from GM Performance. The LS1 Hot Cam is also a good choice, from what I've seen. Obviously, being an LT1 owner, I don't have first hand experience with the cam choices for the LS1, but that should be a good place to start.
Scott
Advertised duration is what the cam maker considers the total open time of the valve, and it is usually a higher number than "duration @ .050
Duration @ .050" means the amount of time, in degrees of rotation that the valve is open between ..050 open and .050 closed. Duration @ .050" is the best way to compare cams.
Lift is the peak amount that the valve would be open, in inches.
The higher the lift and duration, the more air can get into the cylinders, thus more power. But, the longer the valves are open, the less vacuum is created, causing idle and low speed driveability issues. It's a comprise between top end power, and low end torque/drivebility.
A good cam, from what I've heard, thatdoesn't have much effect on driveability and idle is the Z06 Cam from GM Performance. The LS1 Hot Cam is also a good choice, from what I've seen. Obviously, being an LT1 owner, I don't have first hand experience with the cam choices for the LS1, but that should be a good place to start.
Scott
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