94-95 $EE xdf (EEXTRA)

[jthompson122183]

the End of injection table if from the TC definition


Capture2.JPG




i dont have specifics related to this pcm, maybe @Kur4o will post what he has learned.


here is some info ive found about injector timing

https://www.hptuners.com/forum/showt...njector-Timing

https://www.hptuners.com/forum/showt...ight=injection

[kevinodb1]

the End of injection table if from the TC definition


Capture2.JPG

Yes thats the same values as a 1994 Y car manual in Tunerpro, but Tunerpro has a "DEG SPK BTDC" label which may not be correct if its for INJ...

Ive got the new version of Tunerpro working now by reinstalling and rebooting TNX.

Cheers
Kevin

Kevin

[jthompson122183]

Yes thats the same values as a 1994 Y car manual in Tunerpro, but Tunerpro has a "DEG SPK BTDC" label which may not be correct if its for INJ...

Ive got the new version of Tunerpro working now by reinstalling and rebooting TNX.

Cheers
Kevin

Kevin

that was labeling mistake, its taking care of now.

i dont know what TC is referring to "Location" is. From reading those links i would say its some kind of offset before the injector is fired?

[kevinodb1]

That PDF looks very good, ill have a read through, heres a timing diagram I did when we tuned his TR6 with a radical cam, he had it a fair way out.

I have a TR6 engine for my Spitfire and that has the same timing error, not from the factory but that someone has put in at a later date.

What is the "OP" where things reside? Sorry if its a basic question...!

Cheers
Kevin
TR6 INJECTION TIMING V3.jpg

[jthompson122183]

What is the "OP" where things reside? Sorry if its a basic question...!

OP is short for "Original Post" this is were i will add new versions so i don't have to remember which post number had the attachment. Its all good.

[kevinodb1]

Ok have tested 003 from "OP" and all is good.

Cheers

[kur4o]

You can use the following conversion formula for end of injection table.

720-(x*5.625)
The result will be degrees after top dead center.
I still need an osciloscope to confirm my theory. It is partially confirmed due to vilefly awsome scope graphs.

I actually make a patch to control this value realtime through modified eehack program.
I was just about to test how changing this value affect idle quality and one of the injectors died.

kevinobd1 do you have some 96-97 lt1edit bin files to look at. Maybe they are not encrypted and can be edited manually

[kevinodb1]

Hi Kur4o thanks for that.

So are you saying the End Of injection when its set to "6" STD is 33 Degrees ATDC from 0/720, because there is also TDC at 360 Degrees, the start of the intake stroke! We need to be talking about the same place!?

Based on the article(PDF) above posted by Jthompson it would appear there could also be a table attached to that value that is load/rpm based, that would be VERY useful to find.....

At idle the IPW is 1.4m/s and 18m/s is about 702 degrees at 6500 RPM, so that would be about 54.5 degrees of injection period at idle..

So the best place to end the injection would be about 460 degrees after TDC 0......which is approximately the maximum intake valve open point...see my chart above..

Something to try anyway!

Ok cool. is the EEhack patch available for my 94.

I have LT1 edit file for the 94 and 96..

I have the conversion program that converts 94 files to BINS, it does also convert 96 ones, but I dont know if thats the correct transfer algorithm for a 96.....I can see data in Tunerpro if I open the 96 BIN but its all over the place....as expected.

Shall I post a STD 94 BIN converted from LT1Edit and a 96 one the same?

Cheers
Kevin

[kevinodb1]

It appears, from the label, to be the position of latest closing of the injector, under ideal conditions.

If its set 6 degrees BTDC(Firing) that backs up fuel until the next rotation because the intake valve is already closed.

If its set to 6 degrees BTDC(Induction) thats then been blowing most of the fuel out of the exhaust on overlap, what some call "the valve rock"

To get a 320 degree duration(ADV) cam running properly in a TR6(Only 2500cc) we had to get it right, it would hardly run before that.

So where I am going with this is that if we want to run more than a Hotcam, say an 847 in an LT engine then it may be possible to fix all the issues like cam surge etc by just correcting the Injection timing!

Triumph did not get it correct initially, they had worked it out by 1972, Cosworth of course did know how to do it!

The question is what does the "6" in the table actually mean.........if EEHACK could be made to dynamically change that whilst running that could be very interesting for testing.

The idea being that instead of running the injectors at a duty cycle of 85% or so at WOT, we can drop that down to say 30-40% and time the injection better for a bit more power but more importantly fix up the low end driveability of a more radical cam and overly large injectors for idle.

To give an indication by changing the Injection timing on the TR6 we got a higher idle vacuum at the same revs with the 320 degree cam than with the standard 280 degree one, when its not revving it drives and sounds mostly like a STD car!

Its an realm of possible improvement I have not seen talked about before that I would like to test if someone can sort it out.

However only my 96 is running at present and LT1edit cannot do such things, I wasnt fortunate enough to get Tunercats before it was operationally onsold to JET.

Hence my comments that I was pleased to see some work being done on 96,97's.

Will that lead to a OBD2 XXHACK version?

Cheers
Kevin

[Rocko350]

It appears, from the label, to be the position of latest closing of the injector, under ideal conditions.

If its set 6 degrees BTDC(Firing) that backs up fuel until the next rotation because the intake valve is already closed.

If its set to 6 degrees BTDC(Induction) thats then been blowing most of the fuel out of the exhaust on overlap, what some call "the valve rock"

To get a 320 degree duration(ADV) cam running properly in a TR6(Only 2500cc) we had to get it right, it would hardly run before that.

So where I am going with this is that if we want to run more than a Hotcam, say an 847 in an LT engine then it may be possible to fix all the issues like cam surge etc by just correcting the Injection timing!

Triumph did not get it correct initially, they had worked it out by 1972, Cosworth of course did know how to do it!

The question is what does the "6" in the table actually mean.........if EEHACK could be made to dynamically change that whilst running that could be very interesting for testing.

The idea being that instead of running the injectors at a duty cycle of 85% or so at WOT, we can drop that down to say 30-40% and time the injection better for a bit more power but more importantly fix up the low end driveability of a more radical cam and overly large injectors for idle.

To give an indication by changing the Injection timing on the TR6 we got a higher idle vacuum at the same revs with the 320 degree cam than with the standard 280 degree one, when its not revving it drives and sounds mostly like a STD car!

Its an realm of possible improvement I have not seen talked about before that I would like to test if someone can sort it out.

However only my 96 is running at present and LT1edit cannot do such things, I wasnt fortunate enough to get Tunercats before it was operationally onsold to JET.

Hence my comments that I was pleased to see some work being done on 96,97's.

Will that lead to a OBD2 XXHACK version?

Cheers
Kevin

…….responded wrong I didnt read far enough back

[Rocko350]

the numbers in that table refer to reference time periods in crank degrees. Whole numbers are equivalent to 90*. Make small changes and go check your fuel smell at idle. You will need to redo all your VE and MAF tables. A 409 stroker lt1 here running torque head has its EOIT settings at 6.1 I had to start over with the tune afterwards. Car was running hot and getting out of hand with the fuel being sprayed down the header vs being captured in the chamber. I was able to reduce VE down to 35 in the lower idle area. Using the afr and idle speed command I could push rpm down real low, like 400 rpm low so I could verify combustion stability. Header temps dropped almost 400*F verified with a FLIR camera. It made me a believer. I tried the same settings from an LT4 vette in a car I tuned with a hot cam and set its table to 6.0 from top to bottom due to overlap and it cleaned it right up too. I will be redoing its VE and MAF tables this week. It is real crisp on the throttle now too. I use bosch 3 injectors on both of those cars. One the white 36/lb and the grey 28 lbs on the hotcam car. I do is raise the LT1 fuel pressure up to 58 psi when using the bosch3's too drivability is excellent and it helps with vaporization lost to "retarding" the injection event until the exhaust valve is closed.

Accurate injector data is absolutely critical. I cannot stress that enough. Find a copy of the GM asa vette file and use those numbers for the bosch 3 injectors on an LT1. They will get you 80% there with the low pulse, minimum pulse and voltage offsets. This clears up the split trims others have issues with. I usually set the individual tables to 1.00 and check with thermal camera, but have been using the cylinder to cylinder test in eehack to dial this in for idle.

Beware of injectors that have a wide spray pattern. They are not easy to dialed correctly with offset data due to the amount of fuel sprayed on the port wall.

Ive left out a ton im sure. I got a cold and probably rambled on sorry about that.


Chris

[kur4o]

Accurate injector data is absolutely critical.

You can check this thread for utmost precision.
http://www.gearhead-efi.com/Fuel-Inj...r-Data-for-LT1

About table conversion.
The max value is capped at $6f in code. According to my calculations, $6f is at 90 degrees after TDC and $00 is at 720 degrees after TDC. stock b,y settings are at 270* ATDC and f-body at 180*ATDC. So what are the settings that worked best for you so far?


You can get the latest beta eehack version here
http://www.gearhead-efi.com/Fuel-Inj...ll=1#post71481

It has realtime time control of end of injection time and some other addons.

And some great chart for reference.

[ridiqls]

Hey, I found this forum thru Steve's website. I thought I'd try to learn tuning a little bit starting with simple things like constants and switches. I was able to turn off Vats, skip shift, etc.

I'm trying to figure out if there is a way for me to do the following with the Extra .003 file and TunerPro RT:
- I'd like the EGR solenoid to go to duty cycle 100% any time the car is between 1000 RPM and 2000 RPM. Always commanded on during these RPMs regardless of acceleration or deceleration.

If its possible, I'd like to add another constraint so that the EGR duty cycle goes to 100% after 10mph and turns off at 30mph.

So the requirements would be... EGR Duty Cycle 100% for RPMs range between 1000-2000 AND only at 10-30mph.

Is this possible?

Currently seeing my datalog, my EGR solenoid only turns on my PCM when the car is ACCELERATING. I believe it uses Map, TPS, RPM to figure this out but the car will not turn on EGR at steady speeds.


I found the section for EGR in the xdf file here:
EGR TunerPro RT.jpg


For 260A it says "Enable EGR if RPM is >= THIS (EGRDC=0) ... I'm not entirely sure I understand but the value is set at 1000RPM. 260B is set for 2000 RPM.

So does that mean the EGR will come on always between 1000-2000 RPM or are these the parameters in which EGR would operate if it turned on?

What does EGRDC=0 mean? I couldn't find this.

2614 says EGR max dc% value? And it's set at 93. Does this mean that the EGR duty cycle can only go up to 93%?


Any help appreciated thanks..