I like the ideas, especially the air intake manifold.
But, I cannot be two places at once. Producing the noise requires someone in the vehicle to depress the accelerator. In order to apply your suggestions with the noise occurring, a second person would be needed to manipulate the MAF or spray around the air intake for noise changes.
An acquaintance, who is a mechanic, knows a GM tech who has an extensive background with Gen III engines. He is going to consult on Monday.
Also, I have made an appointment with a local Chevrolet dealer for this Wednesday.
Sunday, March 11th, 2018 AT 12:51 PM