doc

I am using Tunerpro. Which table could I use to help prevent stalling? For example, in backing out of the driveway, and going from R to D,,, or coming to a sudden stop. In these situations the engine RPM drops suddenly to about 500; then picks up. Is this a function only of the Idle Air Control motor?

TZFBird

Granted I'm running TBI, and a different ECU, and am completely new to tuning. I know I've read a few posts about stall saver. I do believe the IAC is what you will be changing as far as stall saver. You'll probably want to do some searching for that and go through and log a few times while shifting into drive and reverse as well as stopping. I've been able to pick up vacuum around idle by leaning it out. Maybe you're still a bit to rich or adding/removing some timing may have some effects.

My first question was going to be converter, but noticed you are running a 3000.

I'll be sure to keep an eye on this post since I'm sure I'll be running into the same problem within a week.

pandin

Are you still using 6E? The stall saver Locations are at LC024 thru 28.

I use
24 350 rpm
25 450 rpm
26 550 rpm
27 300 rpm
28 18 degrees spark adder

What are your Table one Maf values? Your maybe too high at the low settings and getting too much fuel, When I was testing MAF's the highest reading one, would stall when dropping into gear. With those 30# injectors you could be rich at low msec.

Have you lowered the default and min injector time at LC03AC and 03AE, I have mine set at 1.05 down from 1.59. This is from the Ford specs.

Also LC05FE "MAF Min Allowable Flow Grs/Sec" I raised from 3 to 5.
LC0220 "Gms/Sec air flow offset for MAF default" raised from 4 to 5.

One of these is raised to match air flow from opening the throttle blades, this gives the ECM a guess as to how much air is bypassing the IAC.

Some one said to set this at 1/100 of min idle speed with no IAC counts, 500 rpm = 5.

Which is easier TPI or the Space Shuttle?

doc

pandin; I am at work now as I reply. Yes, I use 6E. Giving me the location of data does not help me because I am tuning with TunerPro. I have never gotten into the code itself (OK, I am a dynosaur)

Since the Space Shuttle is about 28 years old and my TPI is 22 years old, the Space Shuttle is easier. BTW: I do work at the Kennedy Space Center, but mostly on the new ARES system which replaces the Space Shuttle.

pandin

I use TunerPro also. I can send you a new XDF that has everything in it. PM me and I will walk you through it.

I work nights and sleep days so replies maybe slow.

If I am a 1951 does that make me a "dynosaur" too?

TXBowTie40

iTrader: (2)

pandin,

I have a similiar engine combo, and am also running 30lb Ford SVO injectors. I looked at the stuff in TunerPro and can't find those addresses.
Anyway you could walk me through it also?
I'm a bit leery of going into it beyond my capabilities and yes, hex code makes my brain squirm. I need to find that address to reduce the injector times down so it will help me tune the richness out of this setup.

pandin

Just save and remove the .doc and it should load into TunerPro.

This is a Mark Mansur original and has been extensively added to by me, it is a work in progress, so there maybe errors but no major ones, that I am aware of. There are also some table changes indicated by Tequila Boy, to whom I am most grateful.

Most of this is derived from the 6E, 32, and 32B hack, If I seen some thing I needed, I just added it to the file. The order is from begining to end and , for my convenience, like things are together. If for some reason the order doesn't suit you feel free to change it.

There are duplicate entries for the same items, I found different names for the same thing in different Hacks, so I made copies. A lot of the time only the conversion is different, the ECM numbers are the same.

I also like to read and do changes in Decimal (base 10, 0-255), it is just easier for me. The Tuner Pro reads and saves in Decimal, so any time you read "X" only in the conversion, it is in decimal. There is a way to convert to hex (base 16, 0-FF) and I use that too but rarely, I just prefer decimal.

doc

My 395 is consuming 13 gms/sec at idle with a BLM value of 126 to 128 in fuel cell 0. Therefore, i conclude that MAF table 1 is properly tuned.

doc

I see in TunerPro that there are three tables for "stall saver". They are titled "Stall Saver Spark Enable RPM Threshold 1",2 and 3. Table 1 is set at 200, Table 2 is 200, and Table 3 is 300. Can someone explain how these tables work and what they do? TIA.

BTW: I do have a wide band O2 that I am running constantly, it hovers around 14.5 to 15.0 while at idle and the BLM value is 126 or 128.

RBob

iTrader: (1)

Check this thread out:

https://www.thirdgen.org/forums/diy-...ver-sa-8d.html

It looks like both $6E and $32 use the same stall saver SA routines that $8D uses. Just different locations in the calibration.

RBob.

pandin

What idle rpm are you using, at 650 rpm my 383 only pulls 7 grm/sec?

It could be your descreened MAF, but with those 128 and 15 AFR, it must really be close to correct.

pandin

This is your cross refefence. LC = location and the numbers are the address, the rpm is the value. Table number is a reference.

At 550 rpm (spark is increased) wrong
at 450 rpm (spark is increased more) wrong
at 350 rpm (spark is increased more) wrong
at 300 rpm (spark added is removed) still wrong

and going up in rpm at 550rpm spark is returned to the idle setting.
Correct but spark is blended from base SA to SA table.

doc

I am trying to actually tune my MegaMAF, which now is a flat screen type MAF stuffed into a 3.5" OD aluminum tube.. I do not like this type of MAF sensor, it seems to be alot more non-linear than the Bosch wire type.

I have the closed loop warm idle RPM set at 850 (Idle RPM VS Coolant Temp. table). So with a 395 VS a 383 and 850 RPM VS 650 RPM, my 13 grams/sec sounds like its about correct for airflow.

But lets stay on the stall saver issue. What does table 1 do for me when the value is 200,,, what happens? If the 200 is RPM, and something only happens when I am down to 200 RPM, then its too late, the engine should stall. So what does the 200 means to me?

RBob: I did read your thread, plus couple others from a search. However, none of these threads explains to me how these tables function. One thread did say that when the engine hits 200 RPM, the ECM throws more timing into the dizzy. Is that correct? But as i said above, my engine will stall for sure when it hits 200 RPM. I would think that the RPM setting should be higher in order to prevent stalling.

EDIT: pandin, sorry just realized your last post. So looks like I should increase my values (200, 200, 300) to what you have (350, 450, 550), for table 1, 2 and 3, respectively. (seems like those numbers are backwards)

TXBowTie40

iTrader: (2)

Thank you pandin!
I loaded your .xdf, lowered the injector times to 1.05, and no more surge! I always felt that the root cause of the surge was the injectors delivering too much fuel and needed to find a way to lower that value.
Now I can actually do some real datalogging, without the values being all over the place from the surging idle.
I need to lower the idle speed a bit, it's idling at 1100 rpm when I want it at or near 850, but you helped me immensely with that file.
I finally feel like I'm on my way with this car.

RBob

iTrader: (1)

From what I can tell of the SS routine there is no SA added at any time. It is the opposite, once the engine RPM drops below an RPM threshold the BYPASS to the distributor is opened and the distributor reverts to the base timing (6* BTDC on a stock TPI engine).

Side note for TZFBird: the TBI '8063/'8746/'7747 ECMs handle the stall saver completely different. None of this applies to those ECMs.

Back to the TPI SS, once the engine recovers from the stall the distributor is re-enabled. The SA is blended back to the commanded value via a blend term. This is the blend term:

LC0028 18 degrees spark adder (the total amount of SA added during SS)

The comment is incorrect. The blend is to prevent a sudden advance in SA. It brings the SA back in from the base setting to the proper commanded setting.

Here are the values used in AXCN with the addresses set up for $6E:

;LC024: FCB 32 ; 400 RPM, IF RPM < ENABLE STALL SAVER SA
;LC025: FCB 36 ; 450 RPM, IF RPM < & RPM > LC026, ENABLE STALL SAVER SA
;LC026: FCB 44 ; 550 RPM
;LC027: FCB 44 ; 550 RPM, IF RPM > DISABLE STALL SAVER SA

Once the RPM drops below the value at $C024 the distributor bypass is opened. The timing reverts to the base setting.

Once the RPM is above the value at $C027 the distributor bypass is closed. Timing is then blended back to the normal value.

The values at $C025 & $C026 are used to enter SS if the engine RPM is dropping to quickly. Note that the value at $C026 is compared to a 50 msec delayed engine RPM value. So in effect constitutes a change in RPM over time test.


Doc, from your first post: "In these situations the engine RPM drops suddenly to about 500; then picks up. Is this a function only of the Idle Air Control motor?"

As long as the ECM doesn't go into SS mode, this recovery is on both the IAC and the idle compensation SA. Although the idle comp SA may not always come into play. What can also be done is to put some additional SA in the main SA table.

You can add a few degrees in the 400 RPM row to help with recovery. If the idle speed is high enough can also use the 600 RPM row.

But I would first disable the SS by zeroing out the RPM thresholds. And then go from there.

RBob.

pandin

Thanks for the correction on the SS SA degrees,

The item is commented as "ADD TO SA BLEND", with a hex value of 32 (Arap 6E) hack and value of 2 (Bua 32) hack.

So what you are saying is, this sets the point where the ECM gives control of the SA back to the ignition modual and reverts from table SA to base SA.

And the blend is the smooth transition from say, a base of 6 degrees to a table value of 20 degrees.

So what is LC028, just a scale factor/multiplier/gain for the blend?

By disabling the SS the ECM remains in control via the SA tables and never reverts back to Base SA???

Would you know offhand what causes the rich fuel spike when going into SS?

RBob

iTrader: (1)

Once the RPM is above the value at $C027 the BYPASS is closed and EST is active.

How the blend works is that the final calculated SA is multiplied by the blend variable. Note that this isn't the value at $C028, but a RAM variable that is changed over time by the value at $C028.

Basically, the 16-bit SA variable is multiplied by the blend variable and divided by 256. So the blend variable is actually a desired percentage of calculated SA variable. With a blend value of 64 the SA ends up being 25% of the calculated value.

On a regular basis the blend TERM ($C028) is added to the blend variable. So as time goes on the blend variable increases until it reaches 255. At which time the SA commanded to the distributor is the same as the calc'd SA.

SA out = SA in.

By disabling the SS the ECM remains in control via the SA tables and never reverts back to Base SA???

Yes, by not going into SS mode the ECM retains control over the SA.

Would you know offhand what causes the rich fuel spike when going into SS?

Most likely either some MAP AE from the manifold pressure increasing as the RPM drops down. Or it is an artifact of the reduction in spark timing.

RBob.

pandin

Thank you very much for this detailed explanation and all the others that you so patiently give.

pandin

Now how to enter the zero.

Double Left mouse click to high light the "Stall Saver Spark Enable RPM Threshold 1" Item in the XDF, after opening and loading the Bin/XDF in TunerPro.

This should open a small square window.

Left mouse click inside the small display, on yours Doc, it should have a "200" in it.

Remove all but one zero.

Left click save.

Double left mouse click on "Stall Saver Spark Enable RPM Threshold 1" again.

Verify that the "200" has changed to "0"

Repeat for all desired changes.

When done.

Go to the very upper left of the screen and left mouse click on file.

Go down to save or save as and save your file by left clicking.

At the bottom of the screen is a not ready display, it will turn yellow and say checksum updated. Then it will flash back to not ready.

At this point your ready to load the bin and try. You can reload the bin to verify everything you wanted to change has changed.

I know this is a very basic step threw but Doc said he wasn't comfortable with updating the values.

Any questions?

doc

Rbob and pandin,, you guys are awesome, thank you very much. I will need some time to absorb all of this. Too many projects, I am spread too thin.

RBob, when will you stop chasing electrons? Maybe as soon as I stop playing with cars.

pandin

This is a close up of a stall from a stock 350 87 TPI 32B bin.