im tired of looking for reliable information on ecu upgrades and decided to ask like a noob.
i have an 04rsxstype with intake,headers,catback. ive heard that ecu reprogramming is all crap, ive read that it adds a lot. i think the later is probably true. anyways, can somebody fill me in lol
n00b
It doesn't account for anything except a cold air intake as far as mods are concerned. Many people have seen lean conditions after going to a race header and wide open exhaust and the reflashes. It's only for a small potion of the rev range however, and it's not too lean. The major thing the reflashes change are ignition advance, VTC (i-vtec) cam angles, vtec switch point, and the rev limiter. I believe fuel was relativly un touched from the answers I've seen in the past on this question.angloboi wrote:lol thanx. except i still dont see how a reflash can account for the aftermarket products, sounds like it just extends redline and lowers vtec.
The truth of the matter is that where the race header leans stuff out, the flash is using the same fuel curves, from what I've seen explained in the past.
This means that you would have basically been just as lean without the reflash.
Here's the deal, for basic bolt ons, the reflashes are pretty much the same as running the factory ecu code. Obviously you will net more power with the reflash, however, nothing about the reflash makes it more dangerous to do basic bolt ons from what i'm aware of.
The problems start coming in when you start messing with any sort of forced induction or a VAFC style device.
Nitrous: don't use it with the reflash, the timing is too advanced for it.
Turbo/supercharger: you should be getting a kpro in the first place, or running another 'less advanced' engine management system with the factory ecu code.
AFC devices: any device that adds / removes fuel by manipulating the MAP sensor is going to be incompatible with the new flash. Here's why: As your engine load increases (increased MAP, more air going (potentially) through the engine), ignition is retarded generally. This means that a higher engine load reading will remove timing, and a lower one will add timing. Too much timing creates knock and can damage the engine, not to mention rob power. Too little ignition robs power and can cause EGTs to rise with a forced induction motor. If you used a AFC device to bring your a/f up to 13 from say a 12:1 reading at wide open throttle around 7800 rpm, you would be removing 10% fuel to move about 1 a/f point leaner. To do this, the AFC device will trick the ecu into thinking there is less engine load (MAP SENSOR). If you were to want to remove 10% fuel from MY calibration, you would have to trick the engine into thinking it was loaded less and you would get an increase of 1.5 degrees of ignition. This 1.5 degrees could very likely hurt power and or produce knocking. Bottom line... don't use a AFC device unless you have to... and then, only use it with stock ecu maps since it will have less ignition to begin with, which translates into more magin of error when tricking the engine computer.
Wayne