SophieSleeps

iTrader: (19)

So I hear this stuff all the time. I'm a pure EVO newbie. I made a deposit on one yesterday and am trying to absorb as much as possible.

What exactly does a "flash" do?
From my experience with other OBDII cars, the car has pre-set fuel maps and in closed loop, it make adjustments based on the AF reading from 02 sensors.

So how does the "flash" actually affect this? Is it telling the ECU to reach a different target AF ratio? Raising boost? More agressive timing?

And why would someone use a generic flash on their car? From my experience, every individual car can vary a whole lot even with the same parts. I must be missing something. I doubt everyone on here would be running generic maps.


And wtf is "stage 1" and "stage 2" stuff?
Why does anyone use that terminology? It doesn't tell you anything unless keep track of tuner marketing.

WrX Kila

iTrader: (18)

In a nutshell. The tuner is the one that is programing all these different parameters into the ECU. When you reach a certain power level you have to go a stand alone.

grafix43

are you familiar with hondata and their flashes for hondas at all??? its the same concept here with these tuners except on a turbo motor.... yes it changes the AF ratio, yes it raises boost and some eliminate the taper that occurs need redline (boost dropping of from 19 to 16 etc..) prob changes timing not sure on that exactly.... the flashes arent really general, just depends on what mods you have on your car and they will send you the flash based on that. another IX might get a few more hp than you with the same setup, but its gonna be very similar thats why they have these "general" flashes...

SophieSleeps

iTrader: (19)

But why would someone use a generic type of flash?

What if your generic map makes you go lean?
I guess I just have a lot to learn.

WrX Kila

iTrader: (18)

Are you talking about a mail in flash or Custom Tuned?

occultworks

iTrader: (6)

A person might use a "generic" flash because it has been proven with many vehicles with the same set-up. Sure there may be slight differences, but they are generally safe. You can also get a custom tune for your specific car on a dyno, or on the road, but that costs quite a bit extra. So if you have an evo8 with tbe, intake/drop-in and MBC, those are pretty common mods that have had flashes/tunes done for about a thousand times. Because the tuner might know these types of set-ups so well, then it is easy for them to provide a "generic" tune/flash. If these weren't effective, and were dangerous, then so many people wouldn't be getting them.

Does that help?

SophieSleeps

iTrader: (19)

Somewhat. I haven't seen it in person though. Maybe they're relying on the car's ecu to do most of the work and just changing some base parameters.

I've tuned several cars. And everyone I've tuned varied greatly from other cars with very similar setups. Hell, even a slight boost or exhaust leak can throw your entire map off.

Does anyone here actually know what is done in an ECU flash? No assumptions. But does anyone actually know? No disrespect intended. It just seems like I'm getting the answers that everyone else has heard from everyone else somewhere at some point in time.

FYI, this stems from me reading some thread about having to flash the ECU after an intake...which makes no sense to me.

akemi27

iTrader: (17)

sorry for whoring your thread - if you d/c the negative terminal from the battery would that reset the ecu to stock settings and erase a base flash? just asking...thx

occultworks

iTrader: (6)

Disconnecting your battery would not erase a base flash. The flash takes place of your factory tune, which you won't lose when disconnecting the battery either.

If you really want to get into tuning, you should check out the tuning forums. There's a lot of really good info. You should check out EcuFlash. Relatively new for evos. Gives the user the ability to flash his or her own Ecu.

You would have to get a flash for an intake, from what I understand, for a couple of reasons. One, the intake creates more turbulent air passing through the MAF, making the readings off. Also adding an intake leans you out somewhat, so it neads to be corrected with the tune. Although that doesn't matter quite as much as the turbulent air messing up the signal.

You ask what is done with a flash. Well, there are quite a few things actually. Fuel tables will be edited, as well as timing tables. Also boost may be increased, stationary rev limit can be raised/eliminated/turned into launch control, top speed limiter eliminated, etc.

Check out Dynoflash to see what they offer.

Also check out EcuFlash tutorial for beginners.