Timing question m20b25

[Boostedgmc]

I have a new head torqued on and cam is at tdc but the crank is 90 degrees off. Do I have to take the head off again to put the crank at tdc because of interference, or can I just hand crank it with it on?

[skitzy777]

Take out the spark plugs and rotate the crank towards tdc until you feel the valve touch the piston, do it really slowly and apply minimal pressure. Once it touches rotate it the other direction slightly about 10 degrees and rotate the cam in reverse till you get it lined up.

[Boostedgmc]

For tdc one or your saying the next cylinder at tdc?

[e30davie]

Release all the rocker arms in the head. Then line it all up and then figure out how to reset all the rocker arms again.

[Boostedgmc]

I just took the head off

[skitzy777]

Release all the rocker arms in the head. Then line it all up and then figure out how to reset all the rocker arms again.

Thats essentially impossible to acheive without damaging anything.