What do ECU's REALLY do?
 

Lately I have seen alot of threads regarding how great the third party ECU's are because they add this, add that, add x horsepower, etc etc.

But can anyone here actually tell me what it is the ECU's actually do???? That is, what do they do to get that extra power.

The reason I ask is, I dont want to flash the ECU "just coz" it will give me 8 extra horsepower, or what have you.

And do these thirdparty ECU's affect the lifespan of the engine?

Anyone know?

Well, however one accomplishes this the idea is to improve the tuning parameters of the engine. You lessen the factory 'safety factor' by leaning out the A/F mixture to one that is more ideal for making best power. You add timing into various load ranges optimizing for 93 octane fuel that can improve both throttle response and power. Basically you clean up the factory tuning in such a way that you make more power, even if this removes some of the safety factor that is engineered into the system. Generally with a good tune this isn't a big factor, but if you don't know what you're doing it's entirely possible to shorten the lifespan of the motor significantly.

Matt summarized it pretty well. Also remember that there are things claiming to be "chips" that are not chips at all:

https://www.northamericanmotoring.co...0&postcount=42

Andy, the 1/4 mile database states that you had a MTH ECU mod
on your car. Do you still have it on your car or are you running stock
ECU?

The MTH "ECU Mod" is just an uploaded adjustment to the stock ECU mapping. All it's doing is providing the ECu with a different set of data in its lookup tables. MTH focuses primarily on adjusting ignition timing advance, but also does change the parameters affecting throttle response, the way the DSC works, and increases the redline.

So in answer to your question, it is the stock ECU, but with some updated lookup tables.

Ian

I am asking if Andy still has MTH mapping in his ECU or if he has returned
to stock mapping.

Nope, I no longer have the MTH but I did at the time of that 1/4 mile run. I haven't run yet with my current setup, which is GIAC/19%/380cc injectors.