I figured I'd start a new thread since this is for a different vehicle. I got my dhp tuner and have been playing around with it and I decided to start learning to tune on my 98 GTP since my other car which is getting the turbo is still waiting on some parts. My GTP has a canned tune as well as a cai, slp catback, ubend delete, 1.8 (iirc) rockers and a smaller puller (believe it's a 3.4). Everything was installed by the previous owner.
So I first took some scans and not surprisingly my ltfts were between -8 to -16, also seeing kr once I start making boost. I've come across many guides on correcting this and am going to try to follow those over the next few weeks, however my first big question is do I try to retune the canned tune in the car or do I start from a stock bin and modify from there?