what is the compression on a stock 83 buick regal 3.8?
- DeanoLv 71 decade agoFavorite Answer
GM never gave out what an engine would produce for compression in a psi format. They only give out the piston's comp. ratio like 8.5 to 1. Generally motors from this era were pretty low like stated or maybe in the 9 to 1 area. A compression guage reading should just be all within about 10 psi of each other when comparing cylinder to cylinder during a compression test. The turbocharged motor had a lower compression ratio also. Usually GM motors read somewhere between 140 and 150 psi for all cylinders.Source(s): I was a GM mechanic for years.