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Old 06-21-2010, 09:14 AM   #3 (permalink)
Olympiadis
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Join Date: May 2010
Location: Illinois
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Quote:
Originally Posted by Daox View Post
Welcome to the site white2001s10.
I too own a few of Vizard's books.
What kind of circuits are you looking to build?
Yes, I consider my Vizard collection to be the best of reading and I've read many of them several times. They are great for winter when it's hard to actually work on projects. I have only had the chance to read very few of his online writings like those you mention.

What types of circuits? The type that can read one, two, three, or four inputs, do some very simple logic, and actuate certain functions via electrical signals similar to the ground switching that many factory ECMs use.
I just started reading your thread about using EGR, which I would say would be a prime example of an application for such homemade electronic controllers, if only for testing purposes.

I like to work with the factory ECM/PCM when possible to control functions, but it's not always possible for various reasons. Changing the logic of the algorithms by recoding requires you to have full access to the code and/or some free memory space to work in. Some of the older ECMs keep key parts of the algorithm in ROM, which makes it very difficult to work with. Newer PCMs are even harder, though they have lots of free memory space. The tuning programs out there for newer PCMs only allow a limited (relatively) amount of calibrations to be accessed, and none of the algorithm.

A separate electronic controller that is easily user programmed/adjusted would be the best solution for both testing and use due to the ability to be more universal and function independently of the ECM/PCM.
I am good with coding and wiring, but not quite good enough at designing the circuits to make it work. I know what I want and the logic involved, but do not know which components to solder together to build the circuit.

For example, an EGR controller would want to look at inputs from RPM, VSS, MAP, and possibly CTS. It would need A/D converters, some basic logic, timers or delay relays/switches, and output switching - like a very simple and limited ECM.

Based on engine loading, engine speed, vehicle speed, and whether you are accelerating or in DECEL mode, you could trigger certain functions either on/off or to a certain % duty cycle.

For instance, if you are below a certain road speed and have not accelerated in X.X time, then you could activate your EGR, A/C compressor, alternator charging, (HHO, propane, or water) injection, TCC locking, electric water-pump, Warm-Air induction, etc ...
When accelerating at a certain rate or X.X amount of time (adjustable), you could have these functions turn off in order to increase available engine power.

I have done this sort of switching before using modified factory ECM coding, but only the older GM 165 and 730 models of ECM used to run late 1980s models like the camaros that I own. The problem is that most cars don't have this ECM, and ECM swaps are difficult for many of the newer cars, especially ones that use a PCM. I love working with code, but would actually prefer a little universal controller box.

It could save having a lot of toggles and/or cables to control things and make testing much easier. The easier testing is, the faster and more you can learn.

I find myself manually turning off the A/C compressor when climbing hills or accelerating from a stop. It would nice to free up my attention so I could watch or control other things. I'm sure you know what I'm saying. I just need to find someone who is good at building such circuits as I have too many other projects going on lately to get to it.
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