Usually the dealer says ''that's normal'' which means we don't know how to fix it....:yes
For $12.50 you can fix this, all but too common, problem with the Twin Cam motor. Baisley Performance sells a two oil pressure by-pass spring that goes in your cam plate, one is a LMR#2 and a LMR#4. The LMR#2 will boost oil pressure in your engine by 10~15 lbs and the LMR#4 will get the pressure up 20~25 lbs, for those who use aggressive cams. The Spring will keep a steady pressure in the lifters stopping the lifter from collapsing at inconsistent engine speeds. The job takes about 45 min of your time to do plus a new cam cover gasket. You simply remove the cam cover (some times the pipe has to be removed first) tap out the 3/32'' roll pin remove the spring, install the new spring, tap in the roll pin, install the new gasket and Cam cover and your done. Another advantage to the Baisley spring is it takes 12 to 18 lbs of oil pressure to open the piston jets to cool the pistons, at idle your oil pressure normally drops to around 5 lbs....the jets are shut down....but with the added pressure of the spring you will have 15 to 20 lbs of pressure so the jets are cooling the pistons even at idle.
If you need more info how to do it feel free to ask.
