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View Full Version : TECH ARTICLE: Differences between ECU reflashes



GokuSSJ4
05-30-2004, 11:46 PM
This was posted at: http://www.norcalevo.net/forums/viewtopic.php?t=474&postdays=0&postorder=asc&start=0

An for the people that are looking for a Flash, this is some good info to know .

DavidV of Works fame (now a lone gunman) posted an interesting piece over at EvoM and I wanted to share it with you guys - just in case you never frequent that site.

Here is the link on EvoM, just in case you want to read the exact same info, but on a different site: http://forums.evolutionm.net/showthread.php?s=&threadid=66708

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People need to take the time to understand what it is they are buying, and how it works. Is the $199 product the same as the $599 product because they both use flash technology? Are they the same if they hit similar peak HP numbers? As Shiv correctly pointed out in another thread, take the same car and put each of the three products on it and you will get dramatic enough results that you could tell instantly that the tune is not the same. This is true even if the peak HP numbers are very close.

For example, none of the current flash tuners go about controlling boost the same way. One uses a delay, one removes a pill, and one provides a new tube. They are each necessary to that tuner's approach in an effort to raise and maintain boost, but they each go about achieving that objective very differently.

Dynoflash sends a false 10 minute delay signal to the ECU.

XFlash pulls a restrictor pill from the factory line.

WORKS P2 replaces the factory boost tube with a new boost tube (note, the number of pills remains the same) and the functionality is like stock.

A programmed delay tells the ECU that the built-in grace period for spiking is now extended. Normally, the ECU allows a momentary spike and then regains control over boost and bleeds it off. The 10 minute delay isn't a method of controlling boost, it is a big, long and uncontrolled spike.

Removing a pill does not allow the ECU to control boost. It still bleeds and tapers, even though it peaks higher. When WORKS tried this exact approach, even with the solenoid set at 100% duty cycle, the boost continued to drop off and would not hold steady past 6,000 rpm. This is important, because the factory rev limit is another 1,100 rpm away and the WORKS raised rev limit provides another 500 rpm of useable revs on top of that for a total of 1,600 rpm higher power band. That's an additional 1,600 rpm of sustained, stable boost that the WORKS car is able to achieve.

The WORKS method allows a momentary spike to 19 psi or higher, just like factory approach, but once the boost hits 19 psi, it holds steady until the driver lifts off the throttle. This is because the ECU has regained control over boost after the momentary spike (the built-in grace period) and can hold it to whatever pressure WORKS chooses to set it at (at the moment, only a 19 psi version exists, although theoretically this could be set anywhere).

The method by which boost is manipulated is just one feature that sets each of these products apart. When you begin to look beneath the surface at how each of the tuners goes about setting the air/fuel ratio, ignition timing and rev limit, the products again differ greatly.

The choice of which ECU tune to buy is nowhere near as simple as choosing a ground wire kit or intake filter (products that tend to be more similar in how they work and the results they provide than they are different -- regardless of the brand name they carry) and the consequences in both the short and long term when it comes to ECU tuning are much more significant. Those that are choosing ECU reflashes based on price under the assumption that the existing flashes are all more or less the same have very little understanding of what it is that their $200-600 is buying.

Take the time to become an informed consumer. Tuning your $30k+ Evo's ECU is a big deal. Choose the tuner of your preference, but understand ahead of time how it is that they differ.


An he continues by posting the following :


More DavidV rants:

The "Jiffy Tune":

This is directed at no one in particular, but addresses the second most common criteria for choosing one flash provider over another (the first being the misguided "they are all the same except for price" beleif adressed above). Here, the sales pitch is that a "custom tune" that is "tailored" to your car is inherently better and/or worth more than a "mail order" or "off-the-shelf" flash.

I agree. A custom tune is better and worth more. I have it on me own car... but it cost me over $1,800.00 in dyno time and took over a week to achieve. Do you really think 1, 2 or 3 runs on the dyno or rips up and down the street with a datalogger is even remotely close to a "custom tune"?

It should be apparent that I am not a believer in the "Jiffy Tune." There is nothing a couple of runs on the dyno or street will show a tuner that will trigger a light bulb and allow him/her to customize with any repeatability in mind.

WORKS does not offer this service to the general public, and it is frankly not needed/beneficial. For street-level enthusiasts, this is more of a marketing gimmick, IMO, than a way of adding value.

When WORKS custom tunes for race drivers, they spend weeks doing it -- and it costs a small fortune to do. If a tuner promises you an "optimized" map based on what he/she sees in a relative split second glimpse into your car's existence, be highly skeptical.

What is far more important than a Jiffy Tune are the fundamentals behind how that tuner approaches the Evo in the first place.

It?s like buying a mass-produced CD by a critically acclaimed composer, or having a street performer make up a special song ?just for you? Â*

-- DavidV

trinydex
08-15-2006, 03:18 PM
slight update. nowadays we have ecuflash an open source ecu flashing protocol that bypasses all the licensing fees etc. it has many dedicated people working on it and new doors have been opened in terms of flashing capabilities, roms that were previously unavailable, as well as evoscan which is an odbii diagnostic test port based data logging system with logging capabilities of up to 200 events per second!

paying a lot for a flash is a thing of the past.

please discuss here

http://www.socalevo.net/index.php?option=com_smf&Itemid=26&?topic=26646.msg32194#msg32194