Have just refitted heads on 2v 308 after replacing exhaust valves Maybe I've spent too long in the garage today but can't figure out why when I refit the old cambelts (yes, I am going to fit new, just want to make sure everything is lined up first) both front and rear banks cam pulleys are sitting c. half a pulley tooth out. Flywheel is is on PM 1-4 and have used dial gauge just to double check cylinder 1 at absolute TDC. Marks on all 4 cams spot on with the notch on the cam caps. And they were all perfectly lined up when I stripped the top end down. Before I adjust using the dowel pin, has my addled brain missed something obvious ?
I don't know what you did so I can't tell you. Just go back to basic. 1. Ensure TDC 1 2. Ensure all cam shafts are in the right positions 3. Ensure all cam marks are lined up 4. Install the new belt, tweek the dowel pins to get it tight 5. Tension the belt, whichever way floats your boat.
New head gaskets can change the geometry. Put the belts on as close to the marks. New valves will need to be relashed. From there retime all for cams. The notches are for reference at best.