Was there a formula to this?

Scott

 

Keep in mind I'm an amateur gear-head, like most of the rest of you...

Torque is the force attempting to turn the crank shaft. Therefor, it makes sense that the pistons exerting the highest pressure they are capable of, will produce the highest torque. The highest pressure will occur when you get the most combustible mix into the chamber, and light it at the right moment.
The most combustible mix in the chamber must occur when the length of the intake runners, inertia of the weight of the moving air, valve timing, exhaust pulse reflections, etc. all combine to move the most air into the cylinder, then close the valves and trap it there.
The closer one gets to the "ideal" RPM, the frequency/RPM when all of these pulses combine in a favorable way, will all work more and more together to cram the most air into the cylinder. Either above or below this RPM, at least one ( and probably more ) of these pulses will arrive "out of phase" with the others, and work to the opposite affect, to block or to remove air from the cylinder.
The more finely tuned all of these aspects are to combining at precisely the right moment, the higher the torque output, AND the narrower the band in which it occurs.
Properly aligned, VERY finely tuned, it's possible to have the inertia of the air moving in the intake tract continue cramming air into the cylinder after the exhaust valve closes, while the intake is still open, and if the intake closes at precisely the right moment, before the pressure in the cylinder begins to force the intake charge back to the intake tract, a VE greater than 100% can occur.
( 100% VE being when the engine is pumping through it exactly its full displacement )
A blower ( either supercharger or turbocharger ) can force more air into the cylinder whether these pulses combine, or not, so can produce greater than 100% VE under other conditions.
Nitros contains more oxygen than air, so adding a bottle has almost the same affect as cramming more air, but a slightly less pressure, so will be some-what less effective than a blower. BECAUSE we use the VE table to determine fuel, we need to adjust the VE table to reflect the higher oxygen volume in the cylinder, even though it does not accurately reflect the actual air flow.
( for the same reason the BLM will fluctuate with weather and such, to adjust for the oxygen content of the air and keep the fueling correct for that volume of oxygen regardless of actual CFM of air )
Horsepower is a mathematical construct that tells you when the engine can do the most work. The point at which it's delivering torque rapidly enough that the mass it's trying to move ( the car ) doesn't slow down enough to use up the energy supplied by the previous cylinder firing. SO maximum horsepower will occur at a higher RPM than torque peak, as torque is declining, but total energy output averaged over time is higher than at the torque peak itself.

Torque dictates acceleration, and the feeling in the butt-o-meter, while horsepower dictates speed, but not feeling.

Does this help, or confuse, or am I wrong ?

The idea that if you take out 5.5% fuel in the BPC you can off-set by adding back
5/5% across the board in the VE table, or vice-versa.

 

This may not be accurrate BUT to add fuel to VE tables 95/90 = 1.055

 

So, 65 * 1.055 = 68.575

 

So you are saying my tune will never be any good?

 

than be me !

 

yup but I would only take 1.04 or 1.03...

 

Ha !
No, but it is true that the cam matched to the intake matched to the exhaust matched to the desired RPM can produce a very, very high output, but the EBL can do none of that for you.
What it *can* do, is to optimize the parts collection you have to be the best that they can be.

Therefore, when adjusted "correctly" the arc of the VE table will reflect the torque curve of the engine as it is in the car.

 

I will look at my VE and post "curve". That will tell the tale of my 350 as far as cam, heads, intake, ext etc.

Unfortunately i cannot post due to my Company will block it. No net at home.

 

forgive me for saying this 100% of something is the most it can be .lol

 

agrrrahhh...still a cold idle surge...this is a cold start up! Any ideas on what it may be ?

 

Enrich the commanded AFR during cold operation. Also need to flatten the low RPM/load corner of the VE table.

The IAC steps are too high during warm idle. Open the throttle blades to get the IAC steps in the 20 - 30 range.

Note that there is a lot of random knock counts. Probably false knock, so look for a loose bracket, exhaust rattle and so on.

RBob.

 

Rbob,

i made the changes you suggested, the results did not work out, I have changes the 'IAC-Steps for low batt voltage" set to 0. I have also changed the IAC-Volt Drop for steps...i set this to 25.5.

I have also tried the "Choke" I have added 1 across the board....car would not fire..... i removed 1 across the board from stock....car would not fire.... So i'm back with a great Ve table and good BLM's and a poor starter...GTA

 

o

 

You said you added/subtracted 1 to/from choke... are you talking about the timing? Regardless of adding/subtracting 1 it should fire if it was running before. Is it even trying to start? What's your CRANK - Prime PW set at? I was chasing a no-start issue and it turned out I had turned the prime pw down too far and it wasn't getting enough gas. Turned it back up and I was good to go.

 

Doober,

It was the choke table...i adjusted the AFR + - 1 with bad results.
My Prime crank table is the stock 30005 table that was suplied with the EBL P4.

 

Looking at the log & calibration I noted that your cold start commanded idle RPM are set low. You have the idle in drive set to 750 RPM from 151* C through 8* C (46* F). Then 800 RPM at -4* C and 850 RPM at -16* C.

The cold start log file the engine is at -5* C when started.

The picture is the idle speeds I use in the Camaro. Also, note that the park/neutral idle is higher then the in drive idle.

RBob.

 

RBob

Looks like I will be buying the EBL P4. When you hook up a wideband O2 sensor does the ECM use that to calibrate/learn with say in open loop. I am just now getting on board with this and will be doing a lot of learning.

 

Rbob,

thanks for the look at the tables, i tried them and no more stalling!!! It still does a minor surge at about 30 seconds, by 1.5 min in it ran with no surges.
I flattened out the VE table, and now note at idle my BLM's drop into a hole!
Any thing off idle the BLM's are good.Is the VE table ok to idle at 103-105 BLM? The WB shows 14.7 or so at idle with the BLM's down at 105 or so.
What enable temp should i place the Closed loop enable temp at? It is currently at 50C Is this about right?I tried posting the data log/BIN here but i still get a error even after i compress them, i will send them to you and if you could you post them up again that would be great! Thx GTA......

 

Looked at the log file. Reduce the SA in the choke table:

SA - Startup Choke

Can cut the values in half. Can also reduce the values that are over 9.84 in the "SA - Coolant Comp Spark Advance" table. I'd try reducing by 15% and go from there.

The low BLMs at idle should be corrected. Take the flattened area of the VE table and reduce it. Adjust for a BLM around 128 along with a decent idle.

Can also do a BLM based VE Learn and follow it.

50* C for closed loop is OK. As long as the engine is OK with it, then good to go. I had an engine that didn't like closed loop at 46* C. So bumped it up several degrees and it worked out.

RBob.

 

Yes, the EBL/WUD will do a VE Learn via a WB unit while running in open loop. With a NB O2 sensor it can use the BLM values to adjust the VE when in closed loop. This can be better when starting out with a new set up. Due to the ECM being able to make real time fueling corrections.

RBob.

 

Ok for thoses following this.

1st.
I changed my BPC from 84 to 95 down to 90. Im sticking with 90 at this point it seems to be giving me a good VE range without hitting 100%. I have run enough learn VE to see and feel good results.

2nd.
I had some flat spots on acceleration from a stop sign. I did the following:
Table: AE - MAP PW .
Table: AE - TPS PW .
Both of which I increased the PW only in the areas needed.
NO MORE FLAT SPOTS... Finally

3rd.
This morning I will adjust my cold start a little, that wont be a problem, done this already.

4th.
Timing? should I start looking at the SA Main Table? I Know GRUMPY had posted a lot of information on SA.
I would like it to be a bit more responsive..Will a slow move on advance in the Main SA table help, OR is there a better ploace to get a better Quick acceleration response from the timing tables?

5th.
Ok WHAT NEXT?? What should I be looking for and What can I do to start setting up profiles that give me better:
1. Performance in 4 wheel Drive in the Mountains.
2. Performance in Pulling a Trailer (Torque)
3. Performance in Highway efficiency (fuel mileage)

6th.
What about Launch Mode?

I Know that I have a Good base that will improve over time. Now I want to use that as a foundation to work from.

Scott

1988 1/2 Ton 4 W/D Suburban
383 Stroker (Roller)
Performer Edelbrock Manifold
670 CFM Holley TBI
3" Exhaust No Cat(shhhh), Flow Master 40
190 LPH In-tank Fuel Pump 21 PSI
EBL (Dynamic EFI) Computer

 

Oh forgot...

Do I Really need to turn back on my EGR and Charcoal cannister monitoring in the EBL?

 

any advantage of Polishing the Throttle plates and Barrels of my Holley TBI?

 

Rbob,

thank you for all your advice...i finally have a tune that will fire right up with no surges idles very nicely at or very darn close to 128/128! I note that my BLM's do indeed go down by 2500-3000 rpm to near 108 but I think a few WB learns when the snow goes will take care of that. Again since i for some unknown reason cant post the data log nor the bin i have sent them to you. If you could please look at the Ve lower and upper tables and let me know if everthing looks as it should, thanks again for all your help, it is VERY much appreciated. The EBL P4 Rocks...!!! GTA.;

 

Nope.

Do some research/reading about "boundary layer" technology/theory.

 

Since TBI uses "wall wetting" yikes I hate that term it is better to have na non polished surface in manifold. A slighly abrasive surface(1000grit) may be better to hold fuel when vac drops ...

 

Great Thanks Guys,

Scott

 

Once done with the VE tables can re-enable these.

RBob.

 

Cold start looks good. I emailed one additional suggestion which is to lower the "SA - Idle High Compensation" table values.

Once you can start driving the car more the remainder of the VE table values will come into line. Just go easy on the smoothing factor. Let the VE Learn shape the table values.

RBob.

 

"VERY much appreciated. The EBL P4 Rocks...!!! GTA."

Looks like next month I will have the funs to do this. Maybe sooner.

 

Then call it X-Tau.

http://www.megamanual.com/ms2/xtau.htm

http://video.google.com/videoplay?do...2647555&hl=en#

The idea is to minimize & control fuel that falls from suspension, polishing is counterproductive to both.

 

Years ago my buddy had a problem with wall wetting but it was more due to excessive consumption of JACK.

 

Still looking for answers to this.

 

Well, lean cruise for highway use. Trailer towing may need to reduce the SA a little to avoid detonation. And adjust the PE mode TPS% to stay out of PE when not required. And to go into PE mode to prevent overheating.

For 4-wheeling, may need to alter the spark timing for better control at low speeds.

How the tune ends up depends upon too many variables to be able to say "just do this." You will need to drive the vehicle and see how it is. Adjust and drive again.

RBob.

 

That we would all do well to understand.

Personally, I like my main table to reflect optimum advance at that steady state condition, and use the modifiers to modify advance dynamically is needed.

First thing I see is plural use of "profiles."
Originally, I thought I'd have three calibrations.
One for E-check, one for the trailer, and one for "normal" every day use.
What I eventually discovered is that ONE calibration set up correctly can and will cover all of those bases, with the possible exception of lean cruise during an emissions check. ( oxides of nitrogen, EGR, and such )
I did find it easy enough to "tune around" what E-check looks at.
Pulling a trailer has engine load conditions so much different than day to day that those regions rarely cross over, and not at all under conditions warranting a change in calibration, so the high load trailer areas are only reached under high load acceleration in day to day, and light load cruise is still light load cruise, though at a different load point depending on trailer weight. The way I taper out of lean cruise takes care of that for me, yet still leaves me with the high mileage lean cruise when conditions warrant, such as down hill.

There are times when off-road 4WD ( and my truck is heavier than yours ) where reduced torque could be an advantage. I can see a use for a calibration switch tied to the 4WD lever. RBob ?
Normally, it's not a problem. ( hasn't been anyway )

Methinks that's covered in the docs well enough.
It's a spark modifier to allow the engine to spin up against a converter faster.
There's very low load before the converter comes against stall, so that modifier allows a bit more advance for a limited "launch" use only, when the load is very low.
Lean cruise and launch, both conditions where the demand on the engine is low, an engine can stand and use more advance when there's little mix in the chambers, and much less chance that any detonation will cause much damage.
Doesn't mean that detonation isn't a problem. Juts not *as much.*

 

Great response...Thanks, Its all coming together now that My understanding is becoming Greater.

Thanks again.

Scott

 

LAUNCH MODE.... https://www.thirdgen.org/forums/diy-...unch-mode.html

TIMING ..... https://www.thirdgen.org/forums/diy-...unch-mode.html

 

OK, so here we go. I just finished installing a 5.7L into a 1970 fj40. Replaced the stock ecm with a new EBL-ECM from BobR. Have not changed any settings in the stock bin, just using the wud right now. Here is what I have going on. throwing code 43 knock sensor have not been able to clear since install, replaced IAC, TPS, ICM, PCV, Knock sensor, full tune up inc, cap, rotor, plugs & wires. pulled tbi, cleaned and installed new gaskets. It is also SURGING very bad at idle like it cannot find idle. when it does settle down it idles at 630. Malfunction codes on the wud are IAT (which I do not think I have) ECS and EST which made me think it was the ICM which I replaced. My USB to serial adaptor did not work (not BobR's) I have one coming to me tomorrow so I should be able to make changes to the bin settings then. By the way the KNK is pegging out in about 5 seconds, if I clear the data in the "areas of spark knock" they come back immediately even if the knock sensor is unplugged Any help is much appreciated!!!

Thanks, Phat

 

When not using an IAT un-check the malfunction codes for it: Malf Flags - 12 thru 24 - Bit 1 - IAT23 & Malf Flags - 25 thru 46 - Bit 7 - IAT25.

For the ESC malfunction (43) it is due to the run-away knock counts. Check the knock filter module wiring, power and ground, and to the ECM. The ECM is seeing the constant reporting of knock from the module.

Is the EST error a stored code or an active code? The reason is that opening the EST/BYPASS connector to set the timing will set this code.

If the code is active double check that the EST/BYPASS is closed. If it is then on to the pickup coil and ignition module (ICM). Can also be caused by the ICM harness connectors.

Double check everything that was touched, such as plug firing order, vacuum leaks on TBI, and so on.

RBob.

 

Thanks RBob!! I will look at this today and let you know what I find out.. One thing, I do not have the knock filter as this had an auto in it so I connected the knock sensor direct to the ECM. Is there a problem with this? Do I need to get a knock filter??

Thanks, Phat

 

The "knock filter" is a name given to an electronic module that does considerably more than just filtering.
Yes, you absolutely must have that module installed !
Auto or stick does not matter.

 

Well I just checked the FSM and it seems that the Automatics (which this was) has the KS filter built into the PCM/ECM and is an external unit on the Manual Tranny. So it's off to the bone yard to try and find a filter for my new ECM..
Thanks for the reply!!!

 

Ive tuned out most of the flat spots using the: AE- MAP PW & AE-TPS PW I ended up lowering the AE-TPS and bumping up the AE-Map. seems to be getting there nicely.

Now Sometimes it seems to load up at Idle. When I start out I hit around 110 in mt BLM and it stumbles and falls flat until I gun it. This only happens every so often. Not always Mostly it seems to do well. I have read that adjusting the IAC Steps allowing less air to pass through it and use more of the Fuel thats on the Throttle Plates.

There are 16 IAC Tables....So, what one do I start with or combination?

IAC - Minimum Idle Steps (possible this one)?

This table defines the steps used for the minimum idle steps position adjustment

Scott

1988 1/2 Ton 4 W/D Suburban
383 Stroker (Roller)
Performer Edelbrock Manifold
670 CFM Holley TBI
3" Exhaust No Cat(shhhh), Flow Master 40
190 LPH In-tank Fuel Pump 21 PSI
EBL (Dynamic EFI) Computer

 

The 110 BLM says that the ECM is seeing rich at the O2. What's the duty cycle on the injectors ?

The IAC is adjusted by the ECM to hold idle speed. ( among other things )
Warm idle in neutral, WUD should report around 5 or 10 steps. Mine is set to 5.
This allows enough air through the throttle blades to properly atomize the fuel, shearing it off of the blades and mixing with air. Too many steps, and you have air through the IAC, and fuel puddling up on the throttle blades. Too few steps, and the ECM can not control the idle.
Get the throttle blades right, then worry about the IAC tables later.
To clarify, this is an adjustment to the throttle stop, not the EBL.
If your duty cycle is above 2 or 3 at idle, this alone might correct your loading up problem.

 

so, my D/C needs to be higher? If its at 2-3?

OK D/C is at 3 It was at 4..That is plates just touching closed. BTW My TPS is set correctly.

 

Regarding the knock sensor and the new P4 board. Is not the knock sensor built in on the new P4 board and one is not needed. I see a spot where you can solder one in place. Just wondering.

 

3 should be fine. TPS is self-adjusting ( within reason ) at key-on.
Slightly opening the throttle will lower the IAC steps at idle, and vice versa.
The stop adjustment screw usually has a cap over it that must be removed.

If DC gets down to 1-2 percent, then you have the same condition as at the high end. They spend too much time just trying to open and close again, and not controlling fuel. They get erratic. At the low end, this can be corrected either by lowering fuel pressure, with high end consequences, or by adding a vacuum referenced regulator, to reduce fuel pressure only at high vacuum when fuel isn't needed, thereby adding control range at the low end.
Mine run 2% at the low end. Idle is "mostly" smooth, with some expected erratic behaviour sometimes, but not enough to bother me, nor have a stall problem.

 

The piezo sensor itself screws into the block, or is held clamped to the block by a through-bolt, depending on type.
The "filter" module is internal in some PCM's, and is dependent on the engine for which it is intended, but I don't know which. Bore size is the primary determinant.
( and is how/why a 350 sensor works great on my 455 )
If your filter module was internal in your old PCM, then you need to get an answer from Rbob on that. ( assuming it's not already in the docs )

 

I presume you are idleing CL. 110 BLM is the max range allowed. It cannot pull anymore fuel. You need to lower VE in those cells where you idle(35MAP 750 RPM?) as well as smooten in the surrounding cells.

16 IAC tables? I think the one to use is the IAC/Drive and IAC/Park. coolant referenced I recall. Low coolant temps higher IAC values. You change the variable of idle RPM. Use whatever values are there. If you need top adjust idle RPM at a certain temp you can.

Minimum IDLE steps? Not sure I will guess it is set to like 10 so as to disallow the IAC closing totally to zero steps. Maximum idle steps may be there too. I think mine is set to 200 which is fully retracted.

At idle I am like 5-10 steps for IAC. Often I find out in logs it changes???