Steve's Megasquirt/tunerstudio Help Thread

a91what said:

How to get the proper dead time information will require we jump on the hyperlink bus......
http://www.efidynotuning.com/injdata.htm

We will then select the injector in question.
93-95 Cobra 24LB injectors Blue(Stock)
then hit load.....

In TunerStudio only 2 parameters matter, Deadtime and voltage correction. Dead time is based off of 13.2v so a bit of math is involved.......
13v-.59
14v-.50

.59-.50=.09 .09/10=.009 .009*2=.018 .59-.018=.572

So at 13.2v we have a dead time of .572

For the correction voltage it is ms/v so to do this we will take a mean correction from 12-14v

.81-.59=.22 .59-.50=.09 .22+.09=.31 .31/2=.155

This method of correction is not perfect of course because older style injectors are not as linear as the newer ones are. so the mean method will give you the lowest error. If you do not have heavy electrical loads you may be able to get away with using only positive correction numbers for the voltage correction.
In this instance i would go with a correction of .100


I hope this carifies things.

Click to expand...

This Math needs to be added to your other thread to complete it

a91what said:

I agree and disagree.
- the table does function and does so correctly. Your assumption that refining the curve to your average mat temps may work for the most part. However I have seen in my own logs under boost on a 90* ambient day my mat temps go from 170* at cruise all the way down to ambient (or just above)of 95* after a long 4th gear pull. My AFR was spot on the entire pull I do not use ego correction under boost...
If I had adjusted the curve as you have suggested then the fuel in that much lower temp range would have been much richer.

-simply moving the mat sensor before the TB will alleviate the mat correction issue you are experiencing. Quite a few people do this and then the mat/clt correction table works to keep the AFR creep under control.

I would like to see an adjusted air density table used year round and see the effects. Much cooler air is going to be ingested by the engine I wonder if this would have a negative impact on the tune after the adjustment.

I tuned my car untill the issue you are experiencing was gone, this was done with the clt/mat correction table and a mat sensor in the intercooler piping. I have not attempted to change the density table myself I have however reloaded a correct table to tunes that other have adjusted the table in to correct erroneous errors during high temperature boost.

If you want to tune your own density table and are willing to be a guinne pig....this is how I would go about it. Zero the table out at 100% across the temp range. Then run the car and disable ego correction.... take a drive and datalog.
Using the AFR vs target AFR vs mat temp in the table generator(hopefully you can use all of these fields there) in megalog viewer you will be able to see the needed correction by temp some math will be involved using the fueling equation but I believe this will let you get what you are looking for. It will be time consuming for sure if you need help I am willing to entertain the idea, if it is successful it will make a great writeup.

Edit: I forgot to mention any adjustment to the density table will heavily affect the tune an entire 've table adjustment may be necessary.

Click to expand...

@a91what

I wanted to let you know that I am going to be the "guinea pig" on the tuning of the MAT Air Density Table. I need to make some updates to my tune anyways due to updating my injector deadtime and battery compensation.

I have "0" out the EGO Correction, AE, and MAT Air Density Table (100% to be accurate) to redo the VE Table. Once that is done, I will then be able to re-enable/tune those items again, so I can move to watching the datalogs at different MAT temps to see what % change there is to AFR. I will let you know my findings as they progress.

stanglx2002 said:

@a91what

I wanted to let you know that I am going to be the "guinea pig" on the tuning of the MAT Air Density Table. I need to make some updates to my tune anyways due to updating my injector deadtime and battery compensation.

I have "0" out the EGO Correction, AE, and MAT Air Density Table (100% to be accurate) to redo the VE Table. Once that is done, I will then be able to re-enable/tune those items again, so I can move to watching the datalogs at different MAT temps to see what % change there is to AFR. I will let you know my findings as they progress.

Click to expand...

Ok. For the dead time you can use a datalogs to figure the pw change....

Example:
Dead time 1ms
Idle pw- 2.5
Highrpm pw- 16

Adjusted Dead time. .6ms
Idle pw- 2.1
Highrpm pw- 15.4

2.5/2.1= 1.19 multiply idle range by this amount.
16/15.4= 1.0389 multiply high rpm/load range by this amount.

Now blend the two areas using the interpolate key.

THE DENSITY CHANGE

Old correction- 165*= 84%
New correction 165*= 100%
84-100= -.16

100+(-.16)= 84/100=.84

Multiply entire 've table by .84 to correct the table.

Then shift the density curve to your liking!

Now I have taken half the headache out for you.

a91what said:

Ok. For the dead time you can use a datalogs to figure the pw change....

Example:
Dead time 1ms
Idle pw- 2.5
Highrpm pw- 16

Adjusted Dead time. .6ms
Idle pw- 2.1
Highrpm pw- 15.4

2.5/2.1= 1.19 multiply idle range by this amount.
16/15.4= 1.0389 multiply high rpm/load range by this amount.

Now blend the two areas using the interpolate key.

THE DENSITY CHANGE

Old correction- 165*= 84%
New correction 165*= 100%
84-100= -.16

100+(-.16)= 84/100=.84

Multiply entire 've table by .84 to correct the table.

Then shift the density curve to your liking!

Now I have taken half the headache out for you.

Click to expand...

I do really appreciate you going through all this for me, but some of this doesn't seems to be applicable to me as it would be for the MS3 platform. I am running the MS2 platform, which as far as my knowledge only uses the deadtime and battery compensation. If I do need the other items where are they located at.

I have already multiplied the entire VE Table by .88 to correct my table for the 150* average MAT temperature I have tuning against.

Currently I'm going to leave the entire MAT table at 100% and manually tune it after I get a good VE Table established again. I am curious to see if the MAT table needs to be that aggressive.

stanglx2002 said:

I do really appreciate you going through all this for me, but some of this doesn't seems to be applicable to me as it would be for the MS3 platform. I am running the MS2 platform, which as far as my knowledge only uses the deadtime and battery compensation. If I do need the other items where are they located at.

I have already multiplied the entire VE Table by .88 to correct my table for the 150* average MAT temperature I have tuning against.

Currently I'm going to leave the entire MAT table at 100% and manually tune it after I get a good VE Table established again. I am curious to see if the MAT table needs to be that aggressive.

Click to expand...

What i have outlined will work with all MS based units. I have a micro squirt based diypnp in my mustang.
using a datalog add a line with pw1 or pw2 each of these corresponds to one of two standard injector outputs for a batch fire system.
Example:
on the second line graph you can see duty cycle[white] PW[red] AFR target[green] AFR[yellow]

this is a snip from a log i was sent of an MS2pnp here you can see at a duty cycle of 1.7% the PW is 2.322 here is where we will get our idle pw number for the equation. The same number can be gotten from a high rpm wot run to adjust for deadtime change at high rpm.

Here you can see clearly how a small deadtime change can drastically affect fuel at idle.

No Math needed if you use the manufacturer's data from Ford's website & the Google spreadsheet that he developed (with my input). Good for MS2 & MS3.
EFIDynoTuning doesn't do any calculations. He's only inputted the Ford data. The smaller injectors he lists at 55psi were never tested at that pressure.

Scroll down for Calibration Summaries.
https://performanceparts.ford.com/part/M-9593-LU47

This forum insists on embedding the spreadsheet itself instead of just the link.

View: https://docs.google.com/spreadsheets/d/10c8Iy5SUUmVkLgrrrDhnDFFpDzghk93XajWRFWStqG4/edit#gid=302838282

I like this alot! If it's ok I am going to add it to my tech thread

When it comes to this I'm lost.... Even loster than I wuz

a91what said:

I like this alot! If it's ok I am going to add it to my tech thread

Click to expand...

Give most of the credit to seijirou.
The Excel 'forecast' function is what makes it work so well. It projects values based on a trend.
Can you give link to your tech thread or just put link in your signature?
BTW, TunerStudio rounds off to 3 decimal places. I downloaded spreadsheet & formatted all appropriate cells.

Blown88GT said:

Give most of the credit to seijirou.
Can you give link to your tech thread or just put link in your signature?

Click to expand...

Will do both
https://www.stangnet.com/mustang-forums/threads/megasquirt-tuner-studio-tech-thread.899945/

Spreadsheet didn't embed in your tech thread. Remove this statement in that thread only: This forum insists on embedding the spreadsheet itself instead of just the link.

Change to read: This is the Google spreadsheet that calculates dead time & battery correction voltage.

BTW, the MS firmware developers & all the "experts" on the MSExtra forum say the only way to calculate dead time is by measurement with the actual MS & injectors you are using. I don't believe any home brew measurements will ever be as accurate as Ford's & the difference is so small as to be virtually irrelevant.

Agreed and thanks for proof reading for me work was hell today. Things blew up ive been repairing all day

a91what said:

MAF TUNING

coming soon.

http://www.efidynotuning.com/maf.htm

Click to expand...

Better study this, too. Be aware he's a Quarterhorse/EEC guy, not a Megasquirt guy. Really knows all the Ford EEC's.
http://www.efidynotuning.com/maf101.htm
You will need the data from someone who has actually flowed the meter (housing) on a flow bench.
His transfer curves don't appear to do this. They are directed more towards modifying the factory Ford EEC's.

Every manufacturer of meter housings supplied the flow curves.
Abaco went out of business, didn't last very long.
PMAS is current, but you can get the data directly from them.
BTW, I have all the C&L's; found them on the Internet a couple years ago.
When I was talking to C&L, never thought to ask him for them, since didn't need them at the time.
He sold the business to MAC & retired soon after.
I will attach them here. All Excel files with well labeled file names.
Calibration tube color doesn't need to match the injector size if using Megasquirt.
Use the curve for the color tube you have.

Finally, got out and dyno tuned a little.

You make any changes? I'll review them.

No changes. Unless I did it by mistake.

I have a question,..if you change just the VE table, or just the AFR table for that matter...How does the other one change to match when driving?

Always been a grey area fo me. It makes sense to me that you'd just set target AFRs in the map, and the VE table gets there via EGO correction...I know that that process is capped at 10%+/- ( I think)
AFR's make sense, VE tables are just a bunch of numbers. If you tell the ECU that you want it to be 12:1 in an area, but the current map is at 11.3:1 and its corresponding VE table "VE analyzed" to match, whatdya do to just jump a whole AFR point towards leanie town w/o guessing at the VE table?

madmike1157 said:

I have a question,..if you change just the VE table, or just the AFR table for that matter...How does the other one change to match when driving?

Always been a grey area fo me. It makes sense to me that you'd just set target AFRs in the map, and the VE table gets there via EGO correction...I know that that process is capped at 10%+/- ( I think)
AFR's make sense, VE tables are just a bunch of numbers. If you tell the ECU that you want it to be 12:1 in an area, but the current map is at 11.3:1 and its corresponding VE table "VE analyzed" to match, whatdya do to just jump a whole AFR point towards leanie town w/o guessing at the VE table?

Click to expand...

To simplify the equation.
PW= REQ FUEL* (MAP/100)* (VE/100)* (E [all enrichments])* AFR adjustment [stoic14.7/AFR table]+ DEAD TIME

When you are tuning the AFR table is already set, to change the fuel value we adjust the ve table at that rpm/map point. this in turn affects the pw output.

in this example we are tuning a cruise range at whatever rpm doesn't matter just the map and ve number of the cell matters.
pw=req fuel* 45kpa/100* 100ve/100* (all enrichments including ego)* AFR adjustment [we want stoic for this example] +dead time
req fuel=10 45/100=.45 100/100=1 e=e[no enrichment in this example] AFR= 14.7/14.7=1* DT=1
pw=10* .45* 1* E[lets call this 1]* 1 *1
pw=4.5

lets say this pw results in a lower afr than we want. basic math will get us there. luckily the actual pw is not what we are tuning with we change the actual ve number so the correction is simpler.
we have a afr of 13 but we want 14.7 we just divide what we have by what we want then multiply the ve number by that amount.

have13 want 14.7
13/14.7=.884 now we multiply our ve number above by this amount

ve=100*.884 ve=88.4 this is our new ve number in that cell and will result in a afr of 14.7 instead of 13

now lets see how much that changed out pw
pw= RF10* 45kpa/100* ve88.4/100* E* 14.7/14.7* DT=1
pw=10* .45* .884* E* 1* 1
pw= 3.978 you can see our pw dropped almost.6ms less open time resulting in a lower AFR

now that we have tuned this cell to 14.7AFR we want to lean it out further for gas mileage.... since we already have the ve table tuned so the AFR matchs the AFR table changing the VE table is not the way to go. Lets change the AFR table instead.

pw= RF10* 45kpa/100* ve88.4/100* E* Stoic AFR14.7/ [NEW AFR TABLE VALUE]15.2* DT=1
pw=10* .45* .884* E* .967AFR Table change* 1
pw=3.858 you can see that the AFR table change from 14.7 to 15.2 has reduced fuel by 3.3%

All values in the AFR table are based off of the stoic value of 14.7 when incorporate AFR has been selected in the general settings menu for those of you whom I have helped this is always turned on when I adjust your tune.
In the equation this value acts as a multiplier, you can have 2 VE table cells with the same value but different AFR targets resulting in different output fuel values.

The takeaway here is that if you tune the VE table to a safe AFR value that matches the AFR table you built then when you get to the dyno you only need to adjust the AFR table in that area to get a correct no guesswork AFR output. this is how I did mine I set my AFR table to 11.5 and tuned the VE table to achieve 11.5 on the street then at the dyno I changed the AFR table from 11.5 to 12 and got a dead on 12AFR on the dyno.

"To simplify the equation" he says,....

There's gotta be an el cheapo calculator program that'll let me create that formula so all I have to do is plug in one number to get the other.

Lol. It's real simple

Let's just talk 've table

You have AFR of 13 but want 12

Have/want
13/12= 1.0834

Multiply the 've table in this area by 1.0834 and your now dead on at 12afr.