raising the rev limit

**NebTurboST5** · 02-13-2015

Ok, things you need to add to your scan parameters:

MAF (Hz)
TPS %
Fuel Trim Cell

without at least the MAF frequency parameter you cant use this data to tune. i cant stress this enough DO NOT GO WOT ANYMORE UNTIL YOU GET YOUR MAF DIALED IN. you are locking in at -10 LTFT and 880 on your narrows which is probably somewhere in the upper 12's low 13's afr which is dangerously lean. thats why it starts knocking around 5400rpm. if i was you i would pull 3 degrees of timing until you get it dialed in as well just as an extra precaution. your ltft's vary from -10 to +10 so its just all over the place.

**NebTurboST5** · 02-13-2015

Originally Posted by BillBoost37

Marshall... there are a few tools in the stuff you have that would allow you to load your tune and have it determine what you likely need.

im confused. what are you refering too?

**SgtMarshal** · 02-13-2015

Bill has a dropbox of tuning goodies, and there is a table modifier in it, I think that is what he is talking about

I will add those parameters and take another scan without going WOT

**BillBoost37** · 02-13-2015

In the dropbox stuff you downloaded from me. There's all kinda of tuning guides and tools etc in a folder.

**NebTurboST5** · 02-13-2015

you tune has a lot of tables that need to be changed ill get a list together for you. tables that make the tuning process a lot harder.

**SgtMarshal** · 02-13-2015

thanks

**SgtMarshal** · 02-13-2015

I dont think dhp has a maf hz scan function, I dont see it in the menu

**GTPpower** · 02-13-2015

It might be listed as maf frequency.

**SgtMarshal** · 02-13-2015

Maf raw data I think is all that's available

**GTPpower** · 02-13-2015

What about "mass air flow"?

**SgtMarshal** · 02-13-2015

nope, just maf raw data

I can send you the scan if you want

**GTPpower** · 02-13-2015

The scan won't do any good without the correct parameters.

**NebTurboST5** · 02-13-2015

Originally Posted by SgtMarshal

I dont think dhp has a maf hz scan function, I dont see it in the menu

i know it has it because i use it.

**NebTurboST5** · 02-14-2015

if it where me, here are the tables that i would zero out:

PE RPM vs Time a/f

i dont know if you can get to these others with powertuner but you could download tinytuner and use it.

PE airfuel vs tps
AFR spark modifier

your injectors dont seem to be quite right for 42.5lbs/hr. was your friend using the injector table to adjust the fueling?

so its really not that much to change. looked at your second scan. it looks like you have the correct MAF parameter to be able to log and tune the MAF. i would recommend re-reading the section of the tuning notebook on the MAF tuning. if you have specific questions about the process ask. but im not going to re-write the notebook here.

do you have the excel sheet for tuning the MAF? or another method?

**SgtMarshal** · 02-14-2015

I'm not sure what my friend did to adjust the injectors.

I have the excel sheet to tune the maf, I will take a look at it and see what I can figure out. When you say "zero" out, do you mean literally?

**NebTurboST5** · 02-14-2015

yeah...all zeros in all cells.

**SgtMarshal** · 02-14-2015

Go to the Suggested changes tab and insert your existing MAF table starting at
cell B3 and your reference table starting at H3. Your reference table should be
the original MAF table that is for your MAF. I have an 85mm from ZZP and I
find that the LS6 table works best for me.

I am using a 75mm northstar maf, where do I find a reference table?

**NebTurboST5** · 02-14-2015

jsut pull the one out of your bin file. click on the MAF airflow table. right click and hit export. find the export folder under the powertuner my file path is programfiles/digitalhorsepowerinc. and open the export file. copy the maf values and paste into the worksheet

**SgtMarshal** · 02-15-2015

from maf instruction by damojo: The common mistake that people make is that my O2 values should be 930 assoon as you lock up. Wrong. Most important is that your MAF curve should be
smooth. If you inserted your AFR from the scanner you will notice that your
commanded AFR does not instantly go to your target AFR. Let’s say 11.4 for this
explanation. Notice how the AFR goes from 14.7 to 11.4. You need to do the
same with you desired O2 values. It is important that you do a good scan and
look where your MAF frequency is at the shift. If right after the shift your MAF
is 8000 Hz (random Hz number) and up, then by 8000 Hz you want to be in your
target O2 values. So at that point I would set that at 930. In fact I would go lower
to around 7500 that it is 930 all the way to your shift. Then from the lock up of
7000 Hz (just picked a number here, it should be the cell after your LTFTs lock
up) start feathering your O2s up to the 930. Example: 7000 Hz = 900, 7125 Hz
= 904, 7325 = 908, etc. Hopefully this will help you avoid a spike in your MAF
that you do not want and keep you in your target narrow band range

is he saying that the o2 sensor values should always be 930, but should be feathered from lower values for a smooth transition after the car shifts gears?

**NebTurboST5** · 02-15-2015

hes actually talking about ramp up or tip in fuel. he is saying that before the down shift locks up that you should be in your PE which is done by the computer. you dont really have any control of that because we dont have access to the transient fueling tables. once again tuning off the narrowbands is a bad way of doing it. here is how i MAF tuned using PT without a wideband:

set my PE engagement up 15% above the normal (so my engagement is 30% TPS so i change that table to 45%, some say to shut PE off all together but incase i ****ed up i wanted some protection there.)
go for a long drive just driving normal staying out of PE
during the latter part of the drive i down shift to 2nd and make long pulls all the way to red line (still staying out of PE) if you can find some roads with hills so you can get higher load on the engine that will help push the MAF hz up higher in the table. watch the Hz while you are doing this and get as high in the table as you can. you should be able to make 8000HZ or so. if you get knock back off in a hurry.

then back to the house to analyze the data. Use the excel sheet to plot the data. your new curve will match the old curve in some spots but you will notice sections of it will either be higher or lower then the original curve. what i always did, and a lot of people will say its not right, is take the percent change you got for the last cell you hit (can find it on the calculations page) and multiply the remaining cells out to the end of the MAF table by that value. so the last cell you hit was 8000HZ and the percent change from the calculations page was .023456. i multiple every cell from 8125hz to 11500hz by 1.023456. it will bring the rest of the curve down or up to match a lot better. better yet is a 3rd order polynomial that will best fit your new data but i never had that. im sure its out there somewhere.

once i had my MAF dialed in usually after 4-5 interations of this process (reseting and learning trims in between logs) its on to the PE. for this i feel you need a wideband. even if you cant log the wideband you can just look at it while making the pulls. i always start on the rich side. so lets say you want to run 11.8 afr when its all said and done. i set the PE tables to like 11.2 so you have some cushion. you can make pulls and adjust this up or down depending on what your wideband is saying. if your MAF table is right your wideband will match the commanded PE from the table. if its not it wont bottom line.