To start I have a sierra denali 2002 with true dual, no cats, and whipple supercharger. I tried tuning it by using predator my first time it seems alright. I was on nelson performance and read to remove your whipple computer and install bigger injectors with nelson tune said it would run better. Dont know how that would work because the whipple has some wires going to it dont know what they are for. So wouldnt it be like the whipple without a brain. Can someone help I emailed nelson yesterday and still has not got back to me must be busy because i hear nothing but good stuff from them.