Any feel like having a tuning discussion?

[ChevyHighPerformance]

Originally Posted by f5fstop

As for testing, I understand that no tuner does long term testing prior to releasing a tune; the purchaser becomes the tester. What I was implying is your statement that there was a durability fault with the existing program (and which one, there have been at least two different updates since introduction, and there might be more, I haven't checked in a few months), and GM has quite a few production vehicles out there with high mileage; and some very early mules with tons of mileage, and no major durability problems I know of have been found. Those that were found, were updated with a new calibration, and then nothing really fixed in the new cals with durability.

I see two types of tune: performance and luxury. For the Corvettes, Silverado SS's, and F-bodies, performance is the goal and I'll shoot for a 12.8-12.9:1 A/F at WOT. For the H3 (first luxury tune), MPG is primary then performance and I'm shooting in for a 12.2:1 A/F under WOT. From what I remember on a 350 HP LS1 a 13:1 produced about 3-4 more HP at the wheels than a ~12:1 A/F. So for the H3 at 220 HP, the extra 2-3 HP at 13:1 isn't worth running closer to the edge.

As I go through with a tune, I try to identify the vulnerabilities - where is the engine stressed the most and how much relative stress. I shoot for having the most stress at WOT. However, some tuners leave voids and if you operate the engine in this region the engine stress is excessive.

I've done some tuning and published articles on how to tune, but I don't consider myself a pro like Bryan Herter or Steve Cole. That is one reason why I started this thread to solicit opinions from other people who are tuning.