Quote Originally Posted by Ken1960 View Post
.... It needs a stall convertor just don't have the power it should have. Will a set of aluminum heads bring her around,
Ken, Tech gave you good advice in his post above:
Quote Originally Posted by techinspector1 View Post
...Since you didn't spec out the parts or build the motor, you have no idea of the relationship between the static compression ratio and the cam timing or anything else about the motor, so unless you are willing to tear the motor down and measure everything, get used to continuing problems like this.
Until you know the facts of your motor, either by going back to the shop that built it for the specs, or tearing it down (pulling the heads) for some precise measuring, you're going to be throwing good money away on pieces & parts in a gamble that might yield a little bit better performance, might make things worse or stay the same. Picking the right parts is a science based on knowns, and once you know your engine you can invest your money wisely in parts and pieces that you can feel confident will give good results.
Good luck to you, and hope you have fun with the new to you Chevelle! Oh, and if it popped back through the carb, even a little, you may have just identified one of your problems.