Advertised Compression is: 2-barrel carburetor engine is--8.5:1
The 4-barrel engine is---9.2:1
The normal compression ratio for a 1981 Chevy 305 engine is typically around 8.0:1 to 8.5:1, depending on the specific model and configuration. This ratio can vary slightly based on factors such as factory specifications and any modifications made to the engine. It's important to check the specific engine code and configuration for the most accurate information.
10.5:1
0.045
probably a 3.08
red line's at 5500
yes
Most likely a 2.29:1 ratio
8.3:1 is stock
Yes they will, but 305 heads have a smaller combustion chamber so it may raise your compression ratio.
305 - 165, 350 - 190
No. It lowers the compression ratio and reduces power output.
1.5:1