I had less than 8k on my '04 and had valve float with the stock springs.Ron Vogel said:Just put on stock springs that are newer. Otherwise your burning up HP to run heavier springs for no reason. Stock springs (like any spring) will wear out with time. People say you get valve float with stock springs, but a lot of rocker cars don't get modded until they have 60-70K on them, and by that time the stockers aren't as strong. While you're at it, it's a good time to change the valve stem seals. It's easy, they only cost about $20, and they will greatly reduce KR on a higher mile car.