[Wayne 962]

Where are you located? Some of the chips (while maintaining legality in 50 states) can advance the timing so much that the car detonates. This particularly true with bad west-coast gas. Chips are good because they tailor your car for your needs - not the general needs that the chip was designed for at the factory. Here's some more info:

Motronic (DME) (1984-89) - The Motronic system (also called the Digital Motor Electronics or DME) is hands down the best overall fuel injection system that you can use when you consider price and performance. Ignition timing and fuel delivery are all controlled by a digital map that is recorded in a removable chip within the main fuel injection (DME) computer. The computer takes input from a variety of sensors that are located on the engine – cylinder head temperature, altitude (ambient air pressure), crank angle, throttle position, exhaust gas oxygen (mixture), ambient air temperature, and mass air flow. The DME chip is programmed from the factory with certain performance characteristics (mostly conservative) so that the engine will react well under a host of varying conditions. Major changes to the engine (including the addition of different camshafts) require an updated chip map to take full advantage of these modifications. Failure to update the Motronic system may actually result in a decrease in performance, as the original system is finely tuned to supply the correct timing and fuel injection values for a stock engine configuration.

However, each system is matched directly a specific engine configuration. Because of the proprietary nature of the Motronic system, there isn’t a whole lot of changes that you can perform without updating the DME chip. Major changes to the engine (different camshafts, increased displacement) will not work well with the stock Motronic system because the computer chip is designed to deliver the proper amount of fuel and spark only for a stock engine. To gain the maximum benefit from engine modifications, you need to either upgrade your DME chip, or install a programmable aftermarket engine management system (discussed in the next section).

If you are running a stock engine with the stock Motronic injection, the best upgrade you can perform is the installation of an aftermarket DME chip. As stated previously, the factory programmed the original chip to compensate for a wide variety of driving characteristics. These days, you can find chips that will elevate the rev-limiter, advance your timing, and generally run the engine with less conservatism than the factory chip. The only downside to running a more aggressive chip is that sometimes the timing curves are a bit too advanced and may cause detonation on low-octane pump gas (as it is here in California). It’s best to find a chip manufacturer that offers a few different levels of performance, and will guarantee that you will be happy with the system.

Hope this helps,

Wayne