|
You need to be careful not to make big changes, especially in the intake valve closing point. The fuel injection system may not be able to keep the fuel mixture right if the engine breathes more or less air than the system is calibrated for. This is especially true if you have a MAP sensor instead of an air flow meter to measure engine load.
The original camshaft is not so bad. I like that it doesn't have more duration on the exhaust than the intake and also that it is installed retarded (the intake centerline angle is greater than the lobe separation angle). I'm surprised that it is retarded so much.
If I were going to choose a different camshafts from the chart, I would pick the Jeep 4.2 81-90 camshaft and retard it by 4 degrees with an offset key. This camshaft has a lot less valve overlap than the original, which may help efficiency when the engine operates at low speed and low load.
|