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Whats a cam?

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Old 12-05-2010, 10:29 AM
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Default Whats a cam?

Ok so I know this may be the dumbest question you all have heard but I'm asking anyways. What is a cam? Because I know you can upgrade it and get more ponies. Is that short for "camshaft"??? What exactly does it do and how does it work? Thanks!
 
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Old 12-05-2010, 10:45 AM
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Are you serious?

Yes cam is short for camshaft.

A camshaft opens the valves to a certain lift for a set amount of time (measured in degrees). This is seen in most camshaft spec sheets. I believe the cam rotates once per 2 crank rotations.

On each cam you have:

Duration: Amount of time measures in degrees that each valve is open. This is measured in crankshaft degrees. So if you have 220 intake duration, your intake valve is open for 220 degrees of crankshaft rotation.

Lift: How high the lobe lift is on the camshaft. Multiply this by your rocker ratio to get actual lift of the cam. Note that most people advertise cams for certain cars as the lift with the rocker ratio included.

LSA: Lobe separation angle is the distance between the exhaust and intake lobes. This is measured in CAMSHAFT degrees.

Your cam has to compliment your head design and your duration needs to work with your lift. If not, you'll cut down the flow drastically and can really cut down power as a result.

There's a lot more to it than that. If ya have more questions, I'm all ears :P
 
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Old 12-05-2010, 10:46 AM
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Yes, camshaft. A (non-automotive) cam is an eccentric wheel that rotates to create a motion. A shaft is a stick, rod, etc. The two together makes a camshaft. In an engines case, it has two cam lobes (high and low spots) for each cylinder that rotates with the engine. Riding on the lobes are lifters, and on them are pushrods that push up on the rocker arms, which in turn push down on the valve stems. As a piston goes down, the intake valve will open, sucking in gas. After the fire cycle, the exhaust valve opens as the piston starts coming back up to push gases out the exhaust.
That's the layman's terms. Here's the technical stuff: http://www.tildentechnologies.com/Te...CamBasics.html
 
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Old 12-05-2010, 11:09 AM
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So what all is involved in changing out the cam in a car? Is there anything else you have to change when you change a cam? Because I'm wanting to upgrade but I need to do my research first.
 
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Old 12-05-2010, 11:14 AM
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Here you go:

http://www.ls1tech.com/forums/genera...cam-guide.html

The information on the cam's operation and specs is all universal so it should help you out.
 
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Old 12-05-2010, 11:16 AM
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Universal from a 5.7 to a 3.4?
 
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Old 12-05-2010, 11:20 AM
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The measurements and terms used will be. When it discusses everything Kal brought up and things like that.
 
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Old 12-05-2010, 11:20 AM
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By measrements I mean the units of meaure too, not the exact numbers.
 
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Old 12-05-2010, 11:23 AM
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Ok. so basically I want something to beef up my car. I'm already looking into pace setter headers, SLP CAI, and a Flowmaster Exhaust. Now it's time for suspension, a cam, and tune. This is my DD so it should probably be more on the mild side but I still want to gain a few ponies. Any suggestions?
 
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Old 12-05-2010, 11:23 AM
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Yes, is the simple answer, No it's not a simple bolt on is the anwer. You have to pull the intake and valve covers, then losen the rockers enough to pull the pushrods, the pull the lifters. Timing cover has to come off, probably have to pulll the radiator and the a/c condenser too. Don't know if there is enough room even then, someone else may know. You have to put it all back together too, of course.
Good Luck!
 


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