Picking the Best Olds 403 Heads for Your Build
If you're trying to squeeze some actual power out of a late-70s smog motor, the first thing you probably noticed is that the factory olds 403 heads are basically boat anchors. They were built in an era when Detroit was terrified of the EPA, and the result was an engine with a massive 4.351-inch bore that was completely choked out by its own top end. ...