Just please remember if its stock or slightly modded Comp springs are fine. You only need stiffer springs if you are planning on turning serious RPMs...downside of heavy seat pressure is more force on the cam, rollers(lifters) and pushrods. Great if you are building power but longevity will suffer. All in what you want boys and girls...personally i want longevity...
So most valve springs are supposed to at the “installed height” to achieve the right valve seat pressure for the boost psi. Most guys with stock cams just throw a 0.060” shim and call it a day.
Firelord360 they don’t have that much oil volume to spray out the top so you can let them idle without the covers on without making a mess I recommend it when installing new injectors just to make sure you have not too o ring leaks 👍
When you say running really rough, are you sure it's hitting on all 8? You may have a lifter collapsing or issue with rocker arms/pivot balls. Do you have access to any kind of scan tool with datastreaming? Would be curious to see what the high pressure oil readings are. Hpop may be starting to get tired. Also check the valve cover wiring harness. Cheap to replace and rule that out.
It's know at the local Ford dealership. They have scanned it multiple times and it will read either nothing or something different everytime. I put a friend's PCM in and it ran good 95% of the time, but it still jumped a little. Not nearly as bad as with the original PCM.
