AccessPORT Alpha test started
The boosted ranges (calculated loads above 1.00 or so) will fuel correctly even if you get this method wrong.
What you would do is load a calibrations, drive around for a while and then read your fuel trims - preferably at a couple of different constant engine speeds.
If the trim is more than +/-4 or so, you would select the next calibration on the list in the proper direction - if your trim was positive, you would flash the next level negative on the list. If your trim was negative, you go to the next level positive.
Then, rinse and repeat.
You won't hurt anything by NOT doing this, you just won't see the maximum benefit.
If the trim is more than +/-4 or so, you would select the next calibration on the list in the proper direction - if your trim was positive, you would flash the next level negative on the list. If your trim was negative, you go to the next level positive.
Then, rinse and repeat.
You won't hurt anything by NOT doing this, you just won't see the maximum benefit.
Does the AP datalog or would I need a seperate device/program for that?
Would a tune tweak of this nature be included in the subscription service or something paid for seperate?
Each of the basic calibrations that I ship comes in a spread of different trim levels. You keep trying them until you find the one that fits.
Its like when you go to the eye doctor. He just keeps trying the next lens until he finds the one that works.
If there are specific problems that need to be fixed, then we could go to a custom tune.
Its like when you go to the eye doctor. He just keeps trying the next lens until he finds the one that works.
If there are specific problems that need to be fixed, then we could go to a custom tune.
I agree with RG's assessment that the afterthought by Mazda in putting the third oil squirter in the '09 model is to cover the *** of the other two nozzles.
A little pre-mix makes up for that in our older motors.
I only add 4 oz now.
With my current OMP mapping, the motor consumes about 8 oz (1/8 quart) of oil every 250 miles.
That's not too bad I guess... unless you're getting considerably less than 250 miles per tank.
Are yo currently on backorder for your PO's, or do you have any units that aren't spoken for yet?
Are yo currently on backorder for your PO's, or do you have any units that aren't spoken for yet?
If I was getting more than 250 miles per tank, I'd want more oil.
All the APs on my current PO are spoken for, but I will be making a second PO in two days.
Hey MM,
What sort of gains can we expect from your NA Stg 2 map. Will it work with my K&N v2 and Supercat/Greddy exhaust? Will there be an econo map (I know pretty lame, but thought I'd ask)? As well are you shipping direct to Canada? I'd love to pick one up from you with the additional maps.
Thanks
What sort of gains can we expect from your NA Stg 2 map. Will it work with my K&N v2 and Supercat/Greddy exhaust? Will there be an econo map (I know pretty lame, but thought I'd ask)? As well are you shipping direct to Canada? I'd love to pick one up from you with the additional maps.
Thanks
How is it that Cobb has been able to do this for not only our cars, but Subies, Mitsus, and now even the new Nissan GTR???
They must have a bunch of serious nerds working over there. hehe.
They must have a bunch of serious nerds working over there. hehe.
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From: Misinformation Director - Evolv Chicago
EDIT: D'oh, question answered on previous page.
Last edited by Red Devil; Mar 5, 2008 at 09:30 AM.
I am pretty sure he is using mathmatical equations to calculate the values for multiple different variables. One variable he is calculating is the VE(s). The three main variables in calculating this are Engine Speed, Mass Air Flow, and Intake Air Temperature.
I think he is also calculating the Required Injector Flow Rate. The main variables in calculating this are Mass Air Flow Rate and Air Fuel Ratio. There is also probably a Brake Specific Fuel Consumption calculation going on and he is definately doing some pressure and temperature calculations.
The hardes part is being able to get all of these calculations into common units. For example, Brake Specific Fuel Consumption is claculated by dividing the Fuel Rate in g/hr by the Power in kW. The Power is calculated by taking the RPM * Torque in Nm and dividing that by 9549.27. In addition to this, the BSFC can be calculated in US or Metric.
Hopefully, Jeff will elaborate more...
This number is then used as an axis on all the fueling and ignition tables, referenced against RPM. (Different subsets of tables are selected as a reference to vehicle speed as well.)
There is a preprogrammed limit on this number that the PCM expects to see. If you exceed this limit, a default value is locked in.
All of the OE tables run out at the preprogrammed limit.
In an FI application, we can expect to see significantly more of this "calculated load" than in an NA setup. Therefore, we extend the limits, lengthen the tables and come up with appropriate A/F targets for these new load limits.
Then, everything is rescaled to utilize this new load range in such a way that it is incorporated seamlessly into the regular load range.
Of course, as you can probably imagine, the relationship between load and manifold pressure isn't linear - or even regular - so deciding what is and isn't boost is a bit of a trick since the target A/Fs for these two "ranges" are significantly different.
Then there are the complications of accommodating the variety of intakes (which FUBAR the MAF), injector sizes (which change the scaling) and the little detail of altitude.
In a normally aspirated setup, the OE PCM does some interesting things with the BARO. In a boosted application, this has to be handled a bit differently.
This was a gross over-simplification, BTW.
Don't misunderstand me, I am going to purchase this product and I am excited that Jeff is doing the tuning.
BUT, could someone explain to me in some detail how I can plug in a map for my positive displacement blower and expect it to work without having first been tested on this type of application.
Don't worry about using big words and scientific mumbo-jumbo...I can follow.
BUT, could someone explain to me in some detail how I can plug in a map for my positive displacement blower and expect it to work without having first been tested on this type of application.
Don't worry about using big words and scientific mumbo-jumbo...I can follow.
The OE PCM uses a combination of MAF, BARO, IAT, ECT and APP/TDC to come up with a numerical value that represents the load on the engine at any given moment.
This number is then used as an axis on all the fueling and ignition tables, referenced against RPM. (Different subsets of tables are selected as a reference to vehicle speed as well.)
There is a preprogrammed limit on this number that the PCM expects to see. If you exceed this limit, a default value is locked in.
All of the OE tables run out at the preprogrammed limit.
In an FI application, we can expect to see significantly more of this "calculated load" than in an NA setup. Therefore, we extend the limits, lengthen the tables and come up with appropriate A/F targets for these new load limits.
Then, everything is rescaled to utilize this new load range in such a way that it is incorporated seamlessly into the regular load range.
Of course, as you can probably imagine, the relationship between load and manifold pressure isn't linear - or even regular - so deciding what is and isn't boost is a bit of a trick since the target A/Fs for these two "ranges" are significantly different.
Then there are the complications of accommodating the variety of intakes (which FUBAR the MAF), injector sizes (which change the scaling) and the little detail of altitude.
In a normally aspirated setup, the OE PCM does some interesting things with the BARO. In a boosted application, this has to be handled a bit differently.
This was a gross over-simplification, BTW.
This number is then used as an axis on all the fueling and ignition tables, referenced against RPM. (Different subsets of tables are selected as a reference to vehicle speed as well.)
There is a preprogrammed limit on this number that the PCM expects to see. If you exceed this limit, a default value is locked in.
All of the OE tables run out at the preprogrammed limit.
In an FI application, we can expect to see significantly more of this "calculated load" than in an NA setup. Therefore, we extend the limits, lengthen the tables and come up with appropriate A/F targets for these new load limits.
Then, everything is rescaled to utilize this new load range in such a way that it is incorporated seamlessly into the regular load range.
Of course, as you can probably imagine, the relationship between load and manifold pressure isn't linear - or even regular - so deciding what is and isn't boost is a bit of a trick since the target A/Fs for these two "ranges" are significantly different.
Then there are the complications of accommodating the variety of intakes (which FUBAR the MAF), injector sizes (which change the scaling) and the little detail of altitude.
In a normally aspirated setup, the OE PCM does some interesting things with the BARO. In a boosted application, this has to be handled a bit differently.
This was a gross over-simplification, BTW.
Don't misunderstand me, I am going to purchase this product and I am excited that Jeff is doing the tuning.
BUT, could someone explain to me in some detail how I can plug in a map for my positive displacement blower and expect it to work without having first been tested on this type of application.
Don't worry about using big words and scientific mumbo-jumbo...I can follow.
BUT, could someone explain to me in some detail how I can plug in a map for my positive displacement blower and expect it to work without having first been tested on this type of application.
Don't worry about using big words and scientific mumbo-jumbo...I can follow.
Second, the main concern with the Pettit is just the idle. Once it is in load, it is fueled just like a turbo.
It will suck like all aftermarket MAF housings do, but its nothing that can't be accommodated.
so any chance for the NA maps on getting by with 89 octane like i use to when I had the cz tuned to ~13.0 afr and factory timing (or a little advance)? Or are the maps going to be a tad more aggressive then that?
so realistically MM, are NA users with no cats going to actually feel the difference after the reflash? or will it mainly just be seen on the dyno numbers? or will it differ greatly from one rx8 to another...?
i think i have too much time on my hands, i check this thread way to many times in one day haha...
i think i have too much time on my hands, i check this thread way to many times in one day haha...
First of all - it IS being tested on your application. The map for the Pettit is a Pettit-specific one, not just the general FI calibration. You aren't the only Pettit owner I know!
Second, the main concern with the Pettit is just the idle. Once it is in load, it is fueled just like a turbo.
I am scaling the MAF in the calibration for the new MAF housing.
It will suck like all aftermarket MAF housings do, but its nothing that can't be accommodated.
Second, the main concern with the Pettit is just the idle. Once it is in load, it is fueled just like a turbo.
I am scaling the MAF in the calibration for the new MAF housing.
It will suck like all aftermarket MAF housings do, but its nothing that can't be accommodated.
so realistically MM, are NA users with no cats going to actually feel the difference after the reflash? or will it mainly just be seen on the dyno numbers? or will it differ greatly from one rx8 to another...?
i think i have too much time on my hands, i check this thread way to many times in one day haha...
i think i have too much time on my hands, i check this thread way to many times in one day haha...
I've been mostly concerned with performance - I haven't bothered with bells and whistles.
I'll research that, but worst case scenario you can download whatever that mode is from Cobb.


