Quote:
Originally Posted by p4msi1
John, as I was degreeing in the cam I was thinking about all the events and an N/A IVO would want to be open earlier than a boosted motor because a boosted motor has forced induction. On the other hand an N/A motor may need the EVO sooner to help blowdown and evacuate the exhaust gasses BUT could a boosted motor benefit from a little later EVO to take advantage of the high cylinder pressure at that point and maybe produce a little more HP. You are right about the massive tug-o-war going on in there. I was wondering about the specific cam I will be using. Right now I degreed it as specified on the card and even called the manufacturer and he said to do it to the cam card. I'm not trying to break records BUT if I can take full advantage of this cam then that is what I want and doing it now is what I will do because once it is in the car it will not come back apart.
|
A blower motors Ivo realistically should be able to be open earlier than NA because it has more pressure in the intake manifold vs NA.
Now on a turbo motor could be just the opposite. Because of the back pressure on the hot side of the turbo connecting to the combustion chamber by way of overlap. Can't open the intake valve until the pressure in the cylinder is lower than the inlet pressure!
On a blower motor the back pressure on the exhaust system connected to the combustion chamber through overlap is at atmospheric pressure.!!!!!!!