1988 GMC 5.7 computer to change the parameters

I have a 1988 GMC Sierra 5.7L which has been modified with headers, and cold air injection. is there no way to reprogram the computer to change the parameters. I am looking to gain more fuel economy and horsepower.

You have an OBD1 computer. These are not programmable computer however they have a personalization chip in them called a PROM. These chips can be purchased with various modifications made to them. Just do a Google search on "Performance Chips" and you will see what's available for yours.
 

78 Corvette Pace Car For Sale-18k mi orig-Florida

Thank you, I will do that.
Just keep in mind that your asking for opposing features. Fuel mileage is generally a sacrifice for more power.
78 Corvette Pace Car For Sale-18k mi orig-Florida