ok my friend has a 98 cavalier z24 they changed the cam cover gaskets and timing chain was removed as such well when it was all re installed the car had no compression we did have the timeing off vy the crank at first the most it was off at the crank was 7 tuns retarded and 4 turns advanced everytime they moved it they turned it over 2 full times to ensure the valves werent hitting and there never was a noise to indicate they were. but as it stands the car has all the timing correct valves appear to be fine after inspection and when all is said and done it has no compression its been a pita and i need some help i might be over looking something small here any thoughts i dont think the valves are bent but thats were im going next hopefully someone can explain something to me. so readers digest changed valve cover seal and then no compression thanks a whole bunch in advance