Originally Posted by moneymike 
Originally Posted by SE-Rawkus You should consider kicking over the cams a little higher.
why would you want the cams to switch over a lil higher? on my car i have the cams switching on throttle % and at 3800rpm. i had tuned at a local shop here in south fl and when it was on the rollers i was asked at what point do most people switch there cams over and i said between 4200-5000.
while we were tuning the car was just making more and more power the lower we set the switch point at. then we just left it at 3800, and set it up that it would have to be over 70% throttle to make it crack. so whats the benefits over switching over high?
Very easy...look at the graph. Notice the "dip" in the power band? You can tell that is where the cams are switching over. You get rid of that "dip" by switching the cams over higher where the motor is spinning faster.
The velocity of the air entering the combustion chamber at low RPM is very turbulent if you use a high lift cam. Thus why use use a relatively low lift cam when the motor is not spinning as fast. - it is less turbulent. You have more air in the combustion chamber because the air has moved in more efficiently. The switch over point is defined as the time when you have reached the maximum efficiency of the low lobe and now need to switch to the high lobe to not choke the motor. Fluid dynamics - turbulent vs. laminar flow.
I am not sure I explained myself correctly, but I hope I was able to get my point across.
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