When looking for ways to make your engine produce more power, installing an engine performance chip is often sold as a quick and easy route to huge power gains. The truth behind these chips can really vary depending on the car it is installed in, any modifications present, and how the chip was tuned in the first place.
The reality is that even the most sophisticated ECU adjustment can’t do much to increase power output without modifications to other systems on the car. That being said, ECU tuning is an effective tool for gaining usable, drivable horsepower if you do it right.
Regardless of these factors, there are few things you should understand beforehand before installing a chip into your car.
While power gains can be found in almost any engine by advancing the timing, this isn’t always the safest way to go about tuning. While advancing timing may give you some horsepower, it can often times radically increase an engine’s risk of detonation and potential failure. Sometimes reliability is more important than single digit power gains.
One of the most important functions that your car’s ECU fulfills is regulation of the emissions functions on the car. Sometimes an “engine chip” will disable these systems, which can result in a failed emissions test as well as the “check engine” light coming on. Any chip which deactivates your vehicle’s stock emissions controls isn’t doing your car any good and is probably illegal.
Many chip tuning companies advertise great power gains with dynamometer-proven results. What most of these companies won’t tell you is that the specific conditions and modifications present for these gains may require extensive changes to your engine to reproduce. Tuning is merely part of the puzzle.
There are relatively simple tricks that an engine chip can pull to increase power, primarily during “wide open throttle” during high RPM conditions. The sacrifice is normally a LOSS of power under other conditions, usually having adverse effects on drivability. This means that you are sacrificing overall performance for slightly increased power output during a specific fraction of the time, and it definitely will not make your car faster.
Proper tuning for safe and substantial power gains is best done on an engine per engine basis on a dynamometer by an experienced professional. While a specific tuning setup may work great on one engine in a particular configuration, even the slightest change to climate, weather or differences in modifications to your engine may cause problems.
As a general rule, opening the ECU will immediately void the warranty. Chip installation changes a variety of variables vital to engine operation such as fuel values, ignition timing, knock correction and even fuels cut and redline data. These changes can remove many of the safeguards the manufacturer uses to protect the engine and because of this they almost always end up voiding your warranty should engine damage occur.
Regardless of chip used, power gains are found by altering fuel maps and ignition tables. These changes remove much of the safety and flexibility found in a stock car, and because of this, premium grade fuel and sometimes even an octane booster is generally required for safe operation. Keep in mind these additional expenses when purchasing a performance chip.
Also, engine chip modifications can have negative effects on a vehicle’s gas mileage, especially any chip that alters the emissions control systems of the vehicle in any way. This lost efficiency can be costly, and probably isn’t profiting you anything in terms of horsepower.
Depending on the type of chip used, the method of tuning employed, as well as the car it is installed in, it is possible for the ECU to relearn its old tune. Modern ECU’s are becoming more adaptive and as a result, specific tunes may only be temporary as the ECU can sometimes relearn old tunes in a matter of days or weeks, requiring reboots and clearing of the memory on a regular basis.
While chips can provide noticeable power gains, they are rarely without tradeoffs. These gains can increase the cost of operation and require changes in useable fuel as well as aftermarket octane boosters. Understanding these costs going in, as well the gains you can expect to see and your experience will be far smoother and enjoyable.