[jmt0645]

Originally Posted by martinoledad

On those camshafts on the level 3 it says on one brand that it is a rough idle, and on the other one it says very very rough idle. what does it mean by rough idle and can that be fixed by custom tuning.

with aftermarket cams the engines power band is moved slightly higher with each "stage", by rough they mean the engine is wanting to be higher in the RPMs but can't. for tuning its mechanical and i don't think you can smooth the idle, i may be wrong though.
also on the crower brand it doesnt say it needs lower gears but on the crane brand it says lower gears required.

all the gears do is to help get the engine into its new power band sooner
and what can those springs do
aftermarket springs have more pressure to close the valves faster to prevent valve "float" which will cause SEVERE damage if not used
and as far as the cylinder heads go. it talks about the 5.4 in the description but it only talks about the 4.6 in the applications.

both are "modular" motors, block/heads/cams/cranks, all can be interchanged