well al, me and others have been wondering why it is that you set the low/high octane maps so close to one another. care to enlighten us? most people think that this is to cover up the decaying octane number from knock, but then you and other tuners hint that it's something different. any other tuner i've used is willing to explain to me why they do something that is being done since i am paying for their service and i want to feel comfortable having my car running the provided map. i just figure, why would mitsu put the "safer" low octane map there if it's not really needed and can be made just slightly more conservative than the high map? not trying to start **** here, just looking for an answer that's all. it would make me feel a lot more comfortable using your maps if i knew why. thanks.

 

Why would Mitsubishi put such a restrictive exhaust on the car if they could put a better flowing one on there it would make so much more power. Your question and mine are the same and if you can anwser my question it will answer yours.

 

To have a wider window of fuel quality and to operate in as a seperate mode just in case Joe consumer stupidio puts 89oct in there. Sure the ECU can pull timing just as quick in High oct, but instead of straining the ecu with direct retard in one one mode, it has a seperate low performance mode with a fat fuel map on top.

I keep my timing maps the same, I have no need for retarded failsafe with ignition. I do however keep the low oct fuel map up to two points richer as a tertiary water/methanol failsafe.

 

emissions regulations

 

There is a specific reason to lock the two maps the same - it is a rare occurence which requires it, but those who have run up against it become very frustrated.

If you do lock the two maps the same - the car will still pull timing if it knocks

If you raise all the knock filters to 255 MAX value - the car will still pul timing if it "hears" knock

I am always willing to discuss tuning subjects with my customers - what I am not willing to do is disclose hard earned information about how the stock ecu works on the internet. If you want to discuss what a/f your car is tuned to or what you are looking for in a tune I am all ears to your questions and comments during a tuning sesion or by PM or IM at any time.

Finally - it should be noted that in 95% of the ecus I tune at this time I set the low octane maps much lower as other tuners do. When and if the two maps are set the same it is for a specific reason. Again - 95% of the ecus I do now have the low octane maps set very low on timing and very rich.

 

Good points

In almost all cases a properly tuned car will operate ONLY in the high octane maps

The low octane maps are an additional "limp mode" like protection which goes beyond typical knock retard and enrichment

In most cases I now set the low octane map signifcantly lower - if only for apperance's sake. It cant hurt

Also - these days i set the areas of the map which the car will never run in - e.g. 1,000 rpms full load - etc all to look really nice and smooth - it does not matter that there is no way for the car to reach those load points - I still shade them in with nice fuel and timing values.

Thanks

 

i understand that it will still pull timing. and i understand that if your tune is on, it only runs in the high also. but every once in a while the gas coming out of a pump isn't what it's labeled and it's nice to have a safety net. and this was on an eflash, not a custom tune, so i still don't understand the rare occurence thing.

 

those 2 questions are really not the same thing at all. most exhausts are designed for emmisions and to cut costs. they could've mapped the ecu however they wanted for the same price, and the low map is there for safety. the crap exhaust has nothing to do why the ecu is mapped the way it is.

 

if you emai it back to me I would be happy to make any corrections you would like

free of charge

you can have a saftey net so large that the car wont run if you get bad gas if you like

Al