Custom Tuning Myths and Facts
(Page 2: Continuation of About Custom Tuning...)
Myth: The best tuner can install one tune with optimal results.
Fact: Although generic tunes can perform well, in most cases they are not optimal no matter who you get the tune from. Results vary in different vehicles as demonstrated in these charts. These boost charts were obtained by engine logging. Logs assist a professional tuner in diagnosing engine problems and fine-tuning your ECU. This is essential for true custom tuning service. You will get optimal power and optimal engine life.
Myth: A generic tune works equally well in all elevations and climates.
Fact: Turbos are at greater risk of failure at high elevation. We take into account the client's elevation or atmosphere pressure while creating every tune. Boost will automatically be reduced if you drive to higher elevation. Hotter weather also contributes to warmer intake air temperature and warmer exhaust gas temperature, which affects engine or turbo reliability.
Myth: A tuning box has the same level of adjustability as an ECU custom tune.
Fact: With a tuning box you can adjust boost or fuel quantity in the entire rpm range, but that's where its limitation lies: Your boost+fuel cannot be adjusted at certain RPM points, see the following examples:
|Tuning Box||Custom Tune|
|If your boost curve looks like this and if you want to reduce the boost spike at ~2400 RPM...
... then you may end up lowering the entire boost curve (the blue curve is lowered in the entire 1450-4700 RPM range):
Boost is safer, but less than optimal for performance.
|... however with custom ECU tuning the boost can be fine-tuned at certain RPM points, giving you a flatter curve:
This gives you an optimal power and reliability balance.
A similar case applies to fuel control. If you feel that your car smokes too much between 1000 and 2500 RPM:
|Tuning Box||Custom Tune|
|...then you can reduce fuel with the tuning box. However, it inadvertently reduces power in the entire RPM range:
||.. whereas a custom tune can raise and lower smoke/power at specific RPM points:
With a custom tune you can safely retain extra power in a wider RPM range, while not exceeding the smoke limit. It also lets you control boost-creep at high RPM without affecting performance at other RPM ranges. A custom ECU tune includes a "smoke map", which controls fuel/smoke during partial boost. Taking advantage of this, your vehicle can smoke less while the turbo spools up (from stop lights or while accelerating on the street or highway). Some tuning boxes do not advance fuel timing, which is important for boosting fuel economy, reducing smoke, and squeezing out a bit more power. Fuel flow is governed by many factors such as air mass, sometimes boost pressure, RPM, Torque Limiter, etc. A tuning box will typically alter an input to the ECU to produce a desired output such as increased fuel flow. Often this is done in a way that bypasses safety protocols the ECU uses to govern the fuel flow. Tuning boxes are designed for stock turbo and mild turbo upgrades as they do not scale well to larger turbo upgrades. Some boxes may appear inexpensive at first glance for one of the following two reasons: 1. It is a crude design (plastic box with a simple resistor inside), 2. It only adjusts fuel. A "boost box" must be purchased separately.
A custom tune is cleaner, more efficient, more reliable, and more capable than a tuning box. Here are some more exclusive capabilities in custom tunes:
- Fixes factory flaws, such as the hot-start issue found in '98-99 MK4 Golf/Jetta and New Beetle TDIs. Most '98-99 TDIs require several cranks to start the engine if the coolant temp is warm. All our tunes fix this issue.
- Elevated idle for cold climate or vegetable oil conversions.
- Dynamic EGR control: EGR-on while cold to speed up the engine warm-up period (good for fuel economy, in-cabin heat, and reducing cold cylinder wear & tear), EGR-off while warmed up to minimize or virtually eliminate soot build-up in the intake.
- EGR delete (off-road only) (tuning boxes will not suppress a check-engine light).
- DPF delete in 2009 and newer TDIs (off-road only) (tuning boxes will not suppress a check-engine light).
- Exhaust/hi-flow catalytic converter upgrade in gasoline engines (tuning boxes may not suppress a check-engine light).
- Air Intake Flap delete (common for intake manifold upgrades in some vehicles) (tuning boxes will not suppress a check-engine light).
- MAF sensor delete (tuning boxes will not suppress a check-engine light).
- MAP-sensor upgrade. Many turbo upgrades need a MAP upgrade to allow full boost with factory overboost protection retained. Some tuning boxes will circumvent the factory overboost protection, and you need a boost gauge to see the actual boost.
- 100% VW dealer and VCDS (VAG-COM) compatibility. Tuning boxes skew OBD2 data; the engine computer sees less accurate injection and boost data because the boxes alter them outside of the ECU. They may also skew the fuel economy meter in instrument clusters and aftermarket OBD2 fuel economy meters.
- ... and much more.