Recently purchased a 1977 280Z 2+2 with a 5-speed and 77K miles (I'm told that its 77K actual and the title says the same).
Been doing routine maintenance, and decided to do a compression check. With the engine warm, all spark plugs out, I get an even 110 in each cylinder (+/- 3 PSI), so its balanced across all cylinders. This seemed low to me based on the FSM, so I added a tablespoon of oil to the #1 cylinder and tried again and it went up to 133. The FSM says that its likely the rings and that an overhaul is required.
My only concern is that the car runs great and hardly burns any oil. This is my first Z, so I'm not sure if the performance is lower than normal or not. It generally lacks power below 2K RPM, which may be an indication, but not sure.
Will changing the cam timing (accounting for a streatched chain) affect the compression check? Any ideas on next step?