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Old 11-13-2007, 06:11 AM   #16
Scooby Newbie
Member#: 136833
Join Date: Jan 2007
Chapter/Region: Tri-State
Location: NJ Precision Tuning

Originally Posted by Toolz View Post
When logging the IAM in Enginuity there are two options "Raw ecu data" and "Multipler" I assume we want to log the ecu data value as it is at 16, the multipler is just the value that it can increase/decrease by correct?
Sorry for such a newbie question, I just want to be sure as my value of 16 has never changed which I take to be a good sign.
I am not sure if you are following the IAM fully. Both values represent the same thing. You need to realize how/why they effect timing and how you arrive at Total Timing. A value of 1.00 means you will use 100% of the KC as it is presented in your Advance table. A value of 16 means the same thing, in that you will be using the max values in the total timing equation. Whereas 8 or 0.5 means you will use half of the Advance value as it is in your table.

So, 16 = 1.00(where you end up when the engine is 'happy' over a predetermined amount of time) and 8 = 0.5(where you start after a flash or reset) SOme people find it easier to look at the '16' value because it was all that was available in the original logger def. files for 16 bit ECUs.

I disagree with the statement that the IAM will always drop at some point. I do agree, however, that even on a stock map you will see Negative Feedback Knock... this can be for a multitude of reasons...besides knock. You IAM should remain at 16 or 1.00 with a proper tune.

I also want to stress how different an ECU the 07 is. Many tuners do not realize that you cannot tune it in the same way you would previous model years. They are very different ROM images, with many more maps...for all aspects of the tune. For some of the Maps, it is not even clear how, why or when they come into play. We have a very good idea, but there is definitely much more we can and will learn.

Sorry for the long post, and good luck. With a little patience, and alot of reading, tuning can be a very rewarding aspect to car modification and ownership.
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JMS77 is offline   Reply With Quote