Ltngjim

I already applied the altitude factor to the compression numbers (essentially adding 20%). The actual numbers from the guage were around 90 dry and 110 wet. Lots of ALL CAPS. Guess I hit a nerve here.

Pushed it through again and lined up the 0 degree on the ignition timing scale. Apperanly I was a fraction past TDC. They now line up just like the FSM, so the cam timing is good. I adjusted the vaves and most were just a bit tight. I ran a post adjustment compression check and these are the numbers: 1 2 3 4 5 6 Dry 120 113 113 110 109 112 Wet 137 156 136 132 131 134 These numbers point to worn rings, which requires an overhaul. My gas mileage hasnt been too bad (~20 MPGs on a commute at 50 MPH) and the power seems to be sufficient. Is there any danger to running the engine in the condition and doing an overhaul at a later date?

Digging in now and in the process of adjusting the valves. This is a photo of my timing chain. Appears that its already at #3 (perhaps you can confirm) and the marks are just a bit off. Are they off on the less streatched side or the more streatched side? Thoughts on whether it needs adjusted? Other posts say the line should be just to the left of the V, but it doesnt say how far left is acceptable. As chains streatch does the V move left or right?

The specific compression tester (from autozone) has an 8" hose on it. It has a quick disconnect just below the guage that includes the release valve. There is no way to use the guage without the 8" hose as it doesnt have the correct connectors. I'll keep you updated after I do the valve adjustment this weekend. The FSM calls for a special tool for the valve adjustment. Is that too a necessity?

Where do you place said "chain restraint" device?

I have been reading up on how to check and adjust the cam timing chain. What are people using to lock the chain in place for the adjustment? Seems like some people have a special tool that keeps the chain and crank from moving during the procedure. I will start with checking the valve adjustment and ignition timing, then will check the cam timing. As NewZed said, at least it will give me an idea where all these settings are on a "new to me" engine.

I didnt specifically block the trottle wide open, but I had the gas pedal pushed to the floor. Does that accomplish the same thing? So if I understand this right, the cam timing being retarded can affect the compression in each cylinder. Guess the next step for me is to check the cam timing and adjust if necessary. How do you explain the oil in the cylinder causing the compression to jump 30 PSI, if the possible cause is a streatched timing chain?

Forgot to mention that the pressure in each cylinder will hold steady for 5 minutes without any leakdown. Is it possible I did the compression check wrong?

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?

I guess at $2500 a set I have good taste. Anyone know of any similar wheels for $1000 or less?

Does anyone know what wheels are on this 240Z? They kind of look like PRIMAX, but the center caps are much larger. Any idea on the size. They dont look like the 15x8 that are for sale from MSA. Looking to replicate this setup on my 280Z if anyone knows where to get them.