Cam

[Scooterz]

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)

[DogGear]

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

[Scooterz]

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.

[lively]

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:

[Scooterz]

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.

[TheYellaBrick]

:shock: :shock: :shock: :shock: HEY ! I'm one of them GRANDPAS with a bumpy stick, and I don't need no steeenking blue pill ! Just lots of sleepy time..... 8) 8) 8) 8)

[DogGear]

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

[DogGear]

And BTW
Did you say you had a degree wheel and a indicator with some Vblocks? Not to split Straws , the right ramp angle velocity w/connectiong rod ratio would be a good start ...
thats I quit going to bed ...Marco

[Scooterz]

Dog, I sent you a PM.