Cam
07-29-2011, 02:32 PM
#1
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Cam
Trying to understand full operation of camshafts better.
Say you have two of the same lift & duration cams, but the lobe ramp/degree is different on each. What is the effect to consider w/ how quickly the valve opens & closes?
I know it won't amount to much on my mild street motor; but I just want to understand the function... I just want to know... it's buggin' me.
So this is my cam-101 knowledge so far: (correct me if I am wrong)
How much it opens valves (lift)
How long it keeps valve open (dur)
When it makes valve open (lobe sep degree??)
How quickly it causes valve to open/close (ramp deg)
Say you have two of the same lift & duration cams, but the lobe ramp/degree is different on each. What is the effect to consider w/ how quickly the valve opens & closes?
I know it won't amount to much on my mild street motor; but I just want to understand the function... I just want to know... it's buggin' me.
So this is my cam-101 knowledge so far: (correct me if I am wrong)
How much it opens valves (lift)
How long it keeps valve open (dur)
When it makes valve open (lobe sep degree??)
How quickly it causes valve to open/close (ramp deg)
08-01-2011, 07:14 PM
#2
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Posts: 5
This might help
-Limitation of mechanical geometry , roller , flt, or even mushroom tappets , when mechanical geometry does or does not exceed its limitation, also with these examples the same lobe center seperation would have different valve over lap values - meaning there would be different dwell time and acceleration lift/close at the valve. Something else to think about too much lash will crash the valve into the seats , meaning more bad harmonics for the valve train - [just a general statement of ideas and thought maybe will help maybe not]
-If one man thinks hes better than a another he will never hear a wise mans words- Marco
-Limitation of mechanical geometry , roller , flt, or even mushroom tappets , when mechanical geometry does or does not exceed its limitation, also with these examples the same lobe center seperation would have different valve over lap values - meaning there would be different dwell time and acceleration lift/close at the valve. Something else to think about too much lash will crash the valve into the seats , meaning more bad harmonics for the valve train - [just a general statement of ideas and thought maybe will help maybe not]
-If one man thinks hes better than a another he will never hear a wise mans words- Marco
08-02-2011, 02:14 PM
#3
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Dog:
When considering the small amount of +/- tolerances & the geometry you mention below, I am probably expecting more outcome when I am really "splitting straws" on this thought. There is allot more to the cam that I gave it credit. I was headed for over-camming my motor when I started to understand some of these principles. I also learned that you do not need to wild of lift/dur to get a nice sound on a street motor.
When considering the small amount of +/- tolerances & the geometry you mention below, I am probably expecting more outcome when I am really "splitting straws" on this thought. There is allot more to the cam that I gave it credit. I was headed for over-camming my motor when I started to understand some of these principles. I also learned that you do not need to wild of lift/dur to get a nice sound on a street motor.
08-02-2011, 02:49 PM
#4
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well guys-i know that when that stick with the bumps on it starts spinning then those tube thingis [above the short mushroomis] go up and down and then those rocky horse peices /rock back and forth whick makes the tulip shaped things go up and down/and i do not what happens after that BECAUSE i can't see inside any farther.
DOES THAT HELP ANY RIGSBY 8)
THAT IS CALLED NOLEEDGE :wink:
DOES THAT HELP ANY RIGSBY 8)
THAT IS CALLED NOLEEDGE :wink:
08-02-2011, 04:03 PM
#5
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Yep. In other words, put the right cam in the motor dummy... or it will run like a grandpa on Viagra. You can get some RPMS up, but not much power in curve.
HUH... I can't believe I just said that.
HUH... I can't believe I just said that.
08-02-2011, 05:09 PM
#7
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hey riggs
its a huge discussion but maybe with some thinking we can match the right componets to reach max VE at the desired ie tq/hp curve per rpm.
Or we could look at max intake mach for the desired weight/tq speed/hp oh yea headers too. or maybe an overlap that bleeds gas thats a breather OR hot plug cold plug Vs Overlap,
and this was started because of ramp angles.? what were you saying ~cheers
its a huge discussion but maybe with some thinking we can match the right componets to reach max VE at the desired ie tq/hp curve per rpm.
Or we could look at max intake mach for the desired weight/tq speed/hp oh yea headers too. or maybe an overlap that bleeds gas thats a breather OR hot plug cold plug Vs Overlap,
and this was started because of ramp angles.? what were you saying ~cheers
