Try to keep up. It doesn't "hit" at any rpm.

 

could anyone elborate on power enrichment mode? haha

 

So VVT Is like medicolorians? They are everyware all the time but our engine has a higher medicolorian count there for is more intune with the force?

 

Like said before it doesnt "hit" it is always on, the higher rpm the more drastic the change from say.....idle.

Your valve timing is continuously varying with different engine speed. Hince....CVVT

 

Here's how Volvo (another GM partner) hydraulically adjusts the lateral position of the camshaft for constant VVT. http://www.volvoclub.org.uk/tech/fue...VTfunction.pdf Note that the cam "profile" changes with the lateral movement of the camshaft.

 

Try to make this simple.....the cams do not just go from position "A" to position "B" at a given RPM. They move depending on when the preprogrammed data in the ECU tells them to. They are certainly not going to be in the max-power position at idle. Read up on Camshaft lobe separation if you really want to understand the logic. A carburetor equipped street engine (stock) cam typically has a 114-118 degree lobe separation for smooth idling while a race engine will have a 107-110 degree lobe separation for higher RPM breathing. VVT allows you to have the best of both cams with one set of cams.

 

i get the basics of vvt- cam shaft lobes keeping the vavles open longer for more a/f to come into the engine, but why do i feel a burst of power VERY time i pass 4 grand? i mean i feel it at 3grand but its not as powerful

 

Your in your power band and PE (Power Enrichment mode) has kicked in. PE is a tuning map on the PCM that, that basically says ok your not trying to save on gas anymore you've got your foot on the floor and your past the normal shifting point, its time to advance some timing and make the most power possible.

There is more to it, but thats the basics from what I understand.

 

That is what I was going to suggest for your "boost in power", the timing being changed.

 

my last question would be do we even use sets of cams or is it all controlled by the soilenoids pardon my spelling... thats the only thing i dont quite understand

 

There are 2 solenoids, one for each CAMSHAFT. The Ecotecs all have an Intake camshaft and an exhaust camshaft. Look at the top of your 2.4 engine where the sparkplug coils are -- inside that area of the valve cover look towards the passenger side and you will see 2 wires going to the top of the two solenoids. These solenoids control oil pressure to cam adjusters mounted on the ends of the camshafts. The front (passenger side) of the engine valve cover has two bulges -- those bulges provide the clearance for the cam adjusters. None of the other ecotec motor's valve covers, 2.0 2.2, has these bulges/solenoids/cam adjusters.

 

Interesting discussion. Quite amazing how complicated a motor acutally is. More amazing is how most individuals, including myself, dont realize the intricacies. I personally have take in a ton of information from reading the forums. Not to say that I have learned much of anything, but there is a plether of information on here to keep most of us busy for days to come. I think I get CVVT, but i dont understand it. Not necessarily looking to understand it, as long as it works. xD