Osiris tuner, what are these input fields?

[binder]

I just purchased the osiris tuner package and i'm confused on the software. I've been reading through the manual and it just gets more and more confusing as I go.

Here are some pictures i snagged from another thread. I have circled numbers in red, blue, and pink and i'm wondering what those values represent. It doesn't say what their value means or anything in the manual so i'm a little confused.

One of those is the top tuning. It's tuned RPM verses what? Those numbers don't look like maf voltages and they don't look like MAF values....so what are they?

I've been tuning with innovate datalogger and ss box so this new software is a little confusing to me. Maybe it will be more clear when I get my ROM from uprev. I just need a decent map setup to get me down to Injected performance. I also would like to know how to adjust things on here so i can change my tune later if need be.

Is there a better set of instructions somewhere that explains what each value is? The manual just keeps saying to adjust the K multiplier then log it and adjust and log.

[Arnold K.]

Contact Jared at UpRev.

[binder]

He answered a bunch of my questions in another thread. I was trying to get the answer on the boards verses email just in case someone else was curious about it also. more public knowledge so Jared doesn't have to answer the same email over and over.

[BlinkerFluid]

Alright, I'll take a wack at it. I've been tuning my TT G35 with Osiris for about a year now.

The first picture, the numbers circled in red, that is called Base Fuel Schedule. It is a theoretical fuel injector puslewidth based on cerntain environmental factors. If the factors were whatever standard the pronoun people that programmed the ecu chose, this value would be the injector on time in milliseconds. This value is the ECU uses to reference a load point through the fuel and timing maps. I believe it is created by MAF voltage, K fuel multiplier, the temp compensation table, and I'm sure there are some more multiplier tables working on it too.

Circled in blue is the "Time for max burn pressure" I think it's called. Instead of using an actual BTDC timing value, Nissan uses a time value before max pressure to attempt to align the max cylinder pressure up with its most effective crankshaft position, usually 14-15* ATDC if I recall correctly.

The second picture, circled in pink is the fuel compensation table. By my adjusting this table, it seems to effect air fuel ratio based on RPM and throttle position. If you have a lean spot at 2000RPM and only one spot through the range of the throttle, you can tune it out with this table.

Of course, this is all what I have learned by trial and error, so it may not be entirely accurate, but this is how I have been treating such tables and I haven't popped the engine yet.

Hope this helps.

[binder]

thanks! that does help.

I think part of the confusion is that i haven't gotten my base ROM yet to start looking at this. I'm sure once i put the rom on and watch cipher logs i'll understand better what this stuff is using.

did you use an upgraded PMAS with your TT?

I'm also thinking of using the SS box to tune for boost up past 0psi. Have you done something like that?

[rocks]

Your fuel target under base fuel schedule is the AFR the ecu will try and maintain if do you not change this and try to tune the car you will have a headache. It happend to me. I spent an hour trying to figure out why it wouldn't change the afr. LowDet Timeing maps are for your timing. As the earlier post said nissan does not use "regular" timing numbers.


This is from jared to me.

Base fuel schedule is how Nissan measures the engine load on a bunch of the tables. It's an injector pulse width value. It's the pulse width that the ECU would have to run to maintain a stoich air to fuel ratio based on it's algorithms. So really if you're targeting something other than stoich (which you always are under heavy loads & WOT) it's a theoretical pulse width, not the actual pulse width under those conditions.

In RTT there are quite a few naming inconsistencies (which is why it's not released).
Timing A+B = Low det timing table (the one the ECU should normally be running in).
Timing C = High det timing table (the one it switches to if something is wrong).
Injector scale = K fuel multiplier.
Fuel = AFR Targets.
Fuel Correction = Fuel compensation.

[BlinkerFluid]

Originally Posted by binder

thanks! that does help.

I think part of the confusion is that i haven't gotten my base ROM yet to start looking at this. I'm sure once i put the rom on and watch cipher logs i'll understand better what this stuff is using.

did you use an upgraded PMAS with your TT?

I'm also thinking of using the SS box to tune for boost up past 0psi. Have you done something like that?

Yes, I use a PMAS.

When you get to the point that you max out the stock MAS, you basically hit it's maximum voltage output. The PMAS is rescaled to meter air to a much higher flow rate. So where the stock MAS is sending 5V to the ECU, the PMAS may only show the ECU 2.5V with 2.5V to go. These numbers are notional and used for example only, I don't know what the exact value would be.

Using the PMAS, you reconfigure the MAS Compensation table to change the actual BSF that the ECU comes up with in its calculations. You would also rescale the injectors with the K value and this also changes the BSF.

Now you can go into your fuel table and richen up the BSF columns that are in boost, and go to the timing tables, and remove timing in the same areas so the ECU sees boost as higher load, as it is, and adjusts the fuel and timing as needed.

Additional piggy back controllers for fuel or timing are not needed, and I don't suggest them at all. The factory ECU does a great job, even with boost, when tuned properly.

[binder]

thanks for the input guys.

I'll probably have a lot of questions with these tables once i start running this on the car.