How hard is it to change valve springs with the heads still on the motor? I need to upgrade the stock explorer springs on my gt40ps before something goes wrong. Any reccomendations out there?
It's not that hard. You need a decent valve spring compressor, and you have to pressurize each cylinder with compressed air as you go so the valves don't drop. Also, sometimes the retainers and keepers on the old spring get kinda stuck. Once the cylinder is pressurized , you can put a socket on the retainer and wack it with a hammer to break it loose. I used a set of Comp Cams springs when I did mine. Came with springs, retainers and keepers. The new springs did away with the exhaust valve rotators as well