87 tune
Posted: Thu Mar 25, 2010 11:21 am
have a 2003 silverado ss with 6.0l. factory requires premium. have u7193. was planning to take on trip and wanted to know if the 87 tune would allow me to use reg. gas and get better gas mileage to help save money on my trip. only have cold air kit and flowmaster muffler. going to cut off cats and put straight pipe in soon.