1. The Tuner & Experience
Even though experience is not a material item, it certainly must be considered a valuable 'tool.' By way of experience, good tuners generally know the cause and effect of changes, prior to making them. The collective summary of both good and bad experiences can help seasoned tuners optimize tunes quickly, safely, and correctly. When experience helps nail down a tune quickly, the powertrain is only subject to endure very limited operation under less than optimal conditions. The extended operation of a powertrain under poor control, while a newbie 'learns' to tune, does nothing to preserve an engine. Knowing the safe limits of an engine and practical targets for a tune allow experienced tuners to steer clear of dangerous operations such as delivering too much spark, or too little fuel, or fouling up transmission commands. There's a vast range of opportunity between simply getting a tune to work and getting a tune successfully optimized for the best possible performance. The experienced tuner can typically tell if there's more to be gained, or not; whereas a learning tuner may falsely believe his tune is peaked, when in actuality it is not.
Hiring an experienced tuner is one sure way to utilize this top tuning tool. However, learning from an experienced tuner is also an effective option, and probably more realistic for DIY'ers. Tuning for the first time can be a daunting and risky venture, but it can also be a greatly rewarding experience and something to build on. The only way to gain experience is by tackling the tune yourself. Befriending an experienced tuner to help you learn the process will minimize risk and serve as a great way to bounce ideas off first, before 'testing' them on your powertrain. The tuning process can be progressive as well, starting with simple changes first to get comfortable; and then working up to more advanced tuning as you learn and gain invaluable 'experience' for yourself.
Tuning on a dyno is arguably the best place to complete the process. Above all else, tuning on a dyno is typically the safest place to tune, both for the powertrain and for the people tuning. From a powertrain standpoint, dyno controls can usually be configured to run only within a defined set of safe operational limits; any operation outside of those limits results in a safe and controlled abort of the test. Tuning on a dyno also eliminates the obvious personal hazards (and legality concerns) inherent with tuning on public roads, or at dangerous speeds on a racetrack. Functionally, dynos can easily control load at precisely commanded points. This allows tunes to be evaluated quickly and easily under virtually all operating points-a task not so easy to replicate with no control over load, such as when tuning on streets or race tracks. In addition to offering safe operation and accurate control, dynos are the most effective tool for quantifying performance and measuring gains from tuning changes. Finally, dynos operate under controlled conditions, limiting variables that can otherwise prove challenging to control.
3. The Street and Track
The dynamic response of a vehicle under load in its intended environment (street, track, or both) is practically impossible to duplicate anywhere other than in that environment itself, making the street and track invaluable tuning tools. Even after dialing in a seemingly perfect tune on a dyno, real feedback from street or track testing almost always calls for further tune tweaking and improvement. The dyno is great for creating a tune and establishing bragging specs, but the streets and tracks are for finishing tunes-and are where races are won and lost. For many, access to a dyno is not practical, so the street and track is the only option. Typically, it is possible to complete a tune entirely in the absence of a dyno, especially for a highly experienced tuner; but, it will certainly take more time, more testing, and more effort. At GMHTP, we only condone safe and legal street and track testing, done within the limits of the law and with the benefit of the appropriate safety equipment.