My truck runs about 140 psi, but was rebilt recently.
120psi is normal for a truck with normal wear.
then youre running about 8.5:1 compression
around 80 ft.llbs. or higher is usually good.
head gaskets??? warped heads? did you have them milled?
Knowing the year would make a difference. A good STOCK 350 should have at least 150 PSI per cylinder. You CAN'T have any more then a 20 LB difference in any giving cylinder are you will have idling problems.
Compression ratio on a 1974 Chevy 350 in a Nova was 8.5:1.
Start by testing the compression. It should be consistent within a few PSI on each cylinder. Any cylinders that have little or no compression probably have a burned valve. If all cylinders are up, check the plugs, wiring and distributor.
The compression ratio of a 350 Chevy engine usually ranges from 8.0 and 9.0 to 1. This provides a good balance of fuel economy and power.
Usually at least 140-150 lbs.
8.5 to 1 compression is factory stock.
The ratio is 9.5.1 in the 350 vortec. Doing a compression test you should not have any below 100 psi and all should be similar to each other.
the firing order for a small block Chevy 350 is 18436572
10.5-1