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Message: [QUOTE="Straubtech, post: 1350152, member: 23156"] Let me assure you I did not know who Colt, RCD, or Elite was. When I started on this stuff 3 years ago I started with a clean slate and honestly did not care what he OEM cam was nor what was out there. This is stuff is not rocket science....a diesel is an air pump in constant detonation. A cam is needed to supply demand that comes from the air pump for a given rpm range. Turbo engine gas or diesel are driven by exhaust velocity. The highest velocity reached on the exhaust side is when the valve is open. You want hit that thing hard and quick and shut the valve and continue to do that with each cylinder. Hanging the valve open for longer than is needed is not how you do this. Increasing exhaust duration, time, does not do this. I have not found one engine among the 3 "Tribes" that needs longer duration on the exhaust. If you extend the time of the exhaust valve being open to long all your doing is reducing velocity and helping to cause turbo lag. The duration on exhaust on this cam is shorter....less than intake. The duration on my Duramax is less on exhaust. The duration on my Cummins is the same at .050" on intake and exhaust. Now on the Cummins, this does not mean it is the same lobe. In almost any engine application, since the max exhaust velocity happens at low lift, the rate of decrease of lobe area on the exhaust should be greater than the intake. This is most important in a turbo engine as you want to keep the turbo spooling. Events. In a turbo engine the OEM's open the intake valve early to allow fresh air to mix during overlap and go out the exhaust. This allows for a cleaner exhaust out the pipe. This is not a good way to make power as you have boost working against mechanical force and the more boost you put in the engine the more this battle is increased. For those of you that have bent pushrods, broke cams, cracked pistons....the cause is this internal battle. To make power in a turbo engine, you want to open the intake valve when the piston is at TDC. Doing this, you stop the internal battle and now you assist the piston and blow it down the cylinder helping the engine to accelerate. Size Doesn't Matter. At the end of the day we make power with cylinder pressure. The goal in any combustion engine is to maximize the explosion and we do this with pressure. The one that makes the most pressure wins. Duration and lift are just part of the equation, it is the events that control what we trap for combustion. If you can fill the cylinder quicker then you will need less lift and less duration. If you over cam an engine you have just wasted time. [/QUOTE]