Car: 2006 Chrysler SRT8
Join Date: Apr 2007
Thanked 2,131 Times in 1,929 Posts
The tuner will be safe for your engine. They say not to use a higher octane as the stock tune doesn't require it. Once you install a tuner with a 91 octane tuner, you need the higher octane fuel to protect your engine as the fuel delivery, timing, knock retard and quite a few other engine operating parameters have been changed by the tune.
Stock to tuned HP & torque increases vary. For instance, you'll see a higher result with an aftermarket cold air intake and freer flowing exhaust installed with the tuner vs. stock systems and a tuner. As an example, my car stock made 348 RWHP. With the intake, exhaust and programmer, I netted 378 RWHP. With the addition of the CMR tune on a dyno, my RWHP is now at 411. Dyno results vary and RWHP measurements vary given ambient conditions, vehicle state of maintenance, variations in dyno systems and a few other parameters such as engine internal heat, tire and wheel combination weights, etc...
You can harm your PCM if you do not follow the instructions for loading a tune or modifying a previously loaded tune. Follow the instructions step by step and take NO shortcuts.
My SRT saw about a 3 MPG HWY improvement with the intake, exhaust and tuner installed.
I feel the tuner is one of the best bang for the bucks mods you can make.