What are the different ECU connector styles?

Note:
OBD0 connector style 1984-1991, OBD1 connector style 1992-1995, and OBD2 connector style 1996-2000.
For ease of reference we have annotated the ECU's connector style with OBD designations. However, OBD designations only specify the amount and compatibility of the available diagnostics features and emissions control level of the engine control unit. The actual OBD rating of the car will vary with the month and year of manufacture, state emissions, and car model.

How can I tell if my OBD1 ECU is automatic or manual?

How can I tell if my OBD2 ECU is automatic or manual?

Can ZDYNE supply me with a chip that provides say 3% less fuel or timing?

Yes, but we prefer not to, after all that is what the Super ECU is for!

Regarding preprogrammed "performance chips":
• To take advantage of higher octane fuels and push out of the factory's programmed detonation safety zone you can go with a "performance chip" to:
  1. Lean your mixture about 5% OR just use an adjustable regulator.
  2. Advance your timing OR just spin your distributor.
• Ever notice how everyone's chips do the same things? That's because unlike ZDYNE most chip companies are just brand named chips made with the tools sold by ONE company (TECHTOM).
• We have debunked several chips. For instance just looking at their fuel and timing modifications, I can see that all they did was move all the bytes over one or two locations. The 3D representation of the data no longer looks smooth like the factory, nor will it work as perfectly or as intended.
• Also check out the rev limit section below on unsafe rev limit removal.
• Everyone has heard about chips that loose power, check out the HP FAQ on vtec.net.
• There are also rumors on the net about companies selling chips with stock programs!

Regarding altered "rev limit chips":

We've done some testing of several "chips" currently on the market. We have a dynamic ECU test bench, on which we can effectively spin the ECU's crank RPM to 14000. As you might imagine we use it to test our ECU conversions and prove out their effectiveness at very high RPMs.

There are some things about the stock ECU rev limits you should keep in mind.

1. The stock ECU rev limit is usually about 400RPM over the Redline of the motor. The Redline is the maximum recommend crank spin on the mechanicals of the motor. Exceeding that limit is not recommend in general unless the motor has been properly prepared. (i.e. valve springs, rods, etc).
2. It is usually desirable to raise the stock rev limit by about 300-400 RPM for race shifting purposes.
3. The ECU also has a little known of rev limit we call the Cold Rev Limit which is active until the water temperature exceeds about 180 degrees Fahrenheit (Which may not occur until several minutes after the temperature gauge appears to be "warmed up"). It is usually set about 400RPM below the Hot Rev Limit. You would only notice this if you spin up the motor before it is entirely warm, which is in general not a good practice.
4. Several chips that we have seen claim to have something in the 8000RPM range as a rev limit. This is often not the case. Sadly many chips, when purchased for a specific rev limit, in fact had their limits disabled entirely. For the most part the end user will never realize this, and attribute any failure to the mechanicals of their engine at such high RPM.
5. Revs over 9300 rpm on the stock ECU cause the charge/spark igniter signal to "flip". This will either fire the spark to the wrong cylinder or cause extreme advance or retard. This is yet another reason to avoid simply removing the rev limit.
   Attention Built Motor Users: ZDYNE can reconfigure your stock ECU to function correctly all the way to 12,200 RPM!
6. The stock tachometer is not designed to be accurate in the very high RPM range. Be cautious about making high RPM decisions with it.
7. On the typical D16A engine (240cc injectors with 36psi differential fuel pressure) the rev limit should not be raised over 7800 RPM. This is due to the simple fact that the ECU would be trying to open the injector almost as long as there is time between injection events (a duty cycle issue). Custom applications are available to circumvent this limitation. This usually involves remaping the fuel tables for a smaller baseline pulse width, as can be accomplished with larger injectors or higher fuel pressures.

Ever compare how your turbo kit'ed car compares to a car that came with a turbo or supercharger from its factory?
There are two problems: Fuel and Timing. Read more on this subject!

The features already available on the stock ECU are incredible! This is why you should build upon it instead of throwing it aside. Would you like the following features with your fuel and timing system?

• Perform accurate sequential fuel injection on the cylinders for maximum idle/low rpm stability and emissions.
• Perform variable fuel dispersion to individual cylinders.
• Vary spark charge and timing.
• 3D linearly interpolated load tables.
• Advance/retard sequential injection timing.
• Spark retard and fuel burst of starting condition.
• Throttle "tip-in", or accelerator pump feature that adds a burst for fuel for throttle response.
• Well configured closed loop operation.
• Turn off the fuel injectors when you close the throttle to save fuel.
• Compensate the spark duration for the car's exact battery voltage.
• If the ROM is removed or dies, or even if the microprocessor is removed or dies the car will still start and run, thanks to redundant backups.
• Stock wiring harness and its reliability.
• Great stock response, tune, fueling, timing, emissions, mileage, and reliability (thank you Honda Engineers)
• Maintain "smogability".