Its finally time to learn how to tune!

For those not following my build thread in 'engine swap', its here:
https://www.thirdgen.org/forums/engi...195-383-a.html

basically, what i have is a 383 with a First fuel injection TPI intake, 10.5:1 comp, 228/228 jones cam, 42 lbs bosch III injectors, 255 fp, dyno don headers and y pipe, stock Cat back, 2600 stall in front of a street/strip Pro Built 700r4.

FWIW, the engine was tested and run on an engine dyno with a victor intake and carb setup, it put out 500hp at around 5700, and 500 lbs/ft at 5000.

I have done some(lots) of reading on tuning, but to be honest its hard to absorb much of it until I get into it hands on.
I want to use the factory 165 since its what i have.

I do have some modified arap bins from 'similar' set ups but I feel it would be best to start with a stock arap 6e and learn what each change does as I go along.
Like i said, I am very newb when it comes to this, so i hope you guys can be patient with me as I learn!

For a start up bin, this is what I plan on doing, let me know if there is anything else I should add or change before starting.

-change injector constant to 42
-sync base timing
-pull timing out of arap
-turn off egr

This should get things started for me to begin datalogging.

Couple quick questions:
I keep reading bout the arap fan setup and having to change the settings to work with pre 89?
Anything else I should change in the short term/?

Thx

 

I tuned mine open loop last year really well on MAF. I'm working on my SD setup now(converted last winter) and I'm trying to get it to run right closed loop. Much harder than tuning it open loop.

Do you have a wideband 02 sensor? Hope you plumbed one in while doing your upgrade. I found with mine I had to change the scaling on the MAF tables quite a bit....

 

The flag is "Cooling Fan N/O Req Input"
Set the bit, (apparently vettes need it off)

 

I will definately keep open loop for the time being.


Unfortunately, no WB yet, I do plan on getting one installed soon.

What Wb do you run, and do you have a recommendation?

perfect!

 

Set the timing table how you want to see it. Such as 34 deg at your WOT range and bring max timing in early at around 3200 rpm.

You can zero out the PE power enrichment mode spark advance table and add those values into the main table so that you are working out of 1 table. Its easier this way.

Lock your idle areas to the same timing, that usually helps stabilize idle. Most MAF cars with cams like that will idle around 64-70 LV8 and want an idle speed around 850-900 rpm. So in the cells between 600-1000 rpm and 48-80 LV8 make them all the same. Try 24-26 for starters...may be ok with less may want more. Look at timing table example posted below to describe what I mean. Basically the table I had in my 383, alittle low on timing in cruise areas tho.


Set desired idle rpm vs coolant to whatever you want to command. I'd say 850 rpm when its warmed up, but 1000 rpm when very cold on first cold start and ramp down to 850 as it heats up.


Theres a maximum air flow table vs rpm that you want to modify before driving. From about 2800 rpm on up, you might as well make them all 255 because in that range your gonna be close to maxing out the MAF sensor on WOT pulls from lower rpms. That table puts a cap at whatever grams/sec value you enter, so make it the max possible so the ECM doesnt stop fuel control via MAF sensor. Could add 15-20 grams a second to the values below 2800 down to 1600 to be safe.


Thats all you really need at first to get the motor up and running and moving on its own. Before you go WOT you may want to add a curve to the PE enrichment table vs RPM. But just get it up and running first, do some heat cycles on the fresh motor setup and verify its all in working order, and get it to start and idle well before going for heavy throttle.

Once you get there, let us know

 

Okay, i think I understand it all!
Do I eventually want to return to the PE spark tables, or will all future spark control be provided throught the main spark table only?

 

Main table only unless you want to work from both...its just easier to see actual timing in one table, and not have to add everything up

 

Oh, so the actual timing is the sum of both tables, and what I take ouit of PE has to go into main spark?

 

Yes, whatever is in the PE table, it gets added to the values in the main table. So if you have 34 deg timing at 4000 rpm, and in the PE table you have 5 deg added at 3600 rpm on up to 4400, then you will see 39 deg timing in PE mode. That may be too much depending on what load the engine sees

So I usually zero out PE mode spark table and just work from main table, adding spark in to get the curve I want to see.

I forgot to attach my timing table..... green cells show how i locked timing at idle, blue is how i brought in max spark advance by 2800-3200 rpm.

 

So.... I have been playing with the tuning today. The engine seems to be running fairly well at idle and part throttle.
I am only in open loop at the moment, and won't switch it on until I get open down. In watching the o2 sensor I notice it jumping around alot, depending on engine temp it can vary from a pretty stable 400-600 with some oscilating, and up to 800 plus with wider oscilation as the engine approaches 200f. What should I consider a good o2 range?
Second concern are the knock counts, I seem to get a few at start up which I can understand, but will continue to record a few here and there when I blurp the throttle. Timing got pulled a few times during the intial tuning, but since I tweaked the timing and maf maps its seems more stable and rarely pulls timing.
During a 3 -4 min datalog, its counting about 12-50 knocks. Is this acceptable if its not pulling back timing, can i be getting false knock counts?

 

What is the general opinion on the innovate LM1 WB? I know there were some issues early on, not sure of the the later models.
I found one locally for $200 with about 800 miles of testing/tuning use. Comes as a complete kit, with cables, bung, lighter adapter cable.

I would assume the lm2 has since replaced the lm1 so it is difficult to do a price comparison, I am looking for a temporary install for tuning purposes only.
A lm2 would cost me about 450-500 to my door.
What do you guys think?

 

I am finally getting some progress in the tuning department!

I have been very busy, and have been chasing a silly clanking sound from under the car! I was starting to go crazy until i found out it was a washer/spacer missing ( i forgot to put it in)in my high torque starter. The pinion would work its way out and hit the flexplate what an idiot!

Any hoot, can someone explain what the aldl spark advance is in the scalar section of the 6e mask? Dont know what it does, when, and if I want it or not. It is set at the factory setting of 8*.

I decided that I will most likely tune in closed loop and see how it goes. I have been playing with the blm's, I do tend to be lean at idle and low rpms, playing with the maf tables I can't seem to bump it up enough to make a significant change. Through research, its seems to be the general consensus that it takes little changes to make a difference. Is the maf table where I want to make my changes for blm's?
I prefer to not fool the ecm with injector constant changes, and prefer to make it in the correct table.
Can someone please guide me?

 

ALDL spark adder I believe is additional spark thats added to the motor when in ALDL mode. I think if you connect the scan cable in tunerpro and get it to connect, you will notice rpms jump up abit. I think thats from additional timing thrown in but I cant remember seeing it in the logs but its been awhile since I paid any attention to it. I usually set this to zero since I dont want any spark added by anything but the main table.

MAF tables are used to adjust BLM. Table 1 should be adjusted for idle, changes in 1-2 g/s should be noticeable on a wideband.
Keep in mind the cam overlap effect may skew narrow band o2 readings as well as wideband at times, so BLM's may never come around at idle. Just need to watch wideband and verify it with spark plug readings at idle. Should be a tan color in general.

 

I added MAF voltage to the datastream to make it a little easier to tune the tables.
It makes it so you can make sense of previous datalogs. I just think its easier to change an air flow value at a x voltage instead of changing and airflow value at xx airflow!

 

I need to remove more than add, so I will try to '0' the aldl advance and see what that does.
I will also pay more attention to plugs! Thx

What exactly do you mean by 'added maf voltage to the data stream' ? I am away from the laptop atm, lol. You mean just to place it on your custom dash or a new item in the adx file?

 

https://www.thirdgen.org/forums/diy-...e-tunerpro.htm

The first step is a change in the BIN via the hex editor,

And then you edit the ADX to display the right value. That walkthrough is for tunerpro 4, but there's not much difference, aside from the way the formula is entered.

 

Excellent, I will look into that!

 

Update:
With the adjusting of the pe modes, timing table, and some minor maf table tweaking I have the car running fairly well at idle and most part throttle areas.

Still not able to really get into WOT. My main concern at the moment is the ridiculous amount of knock counts and retarding that is going on. I am starting to think that i am looking at false knock, no matter much timing is being pulled or how many counts i record, I have not physically heard a single ping that would indicate pre- ignition or detonation. The noises I was hearing before was the starter pinion rattling the flexplate, I believe the sensor was reacting to the clanking and pulling the timing back, however, thats another story, and that drama is over!

I have been playing witht the afr (richen to 11.5-12:1)trying to stop the Knock counts, doesn't work, I have also dogged the timing and that does not work, just makes the car a dog! With a 12:1 AFR and around 29-32* of timing, 94 octane fuel, I see no reason for this thing to ping.
I have installed a new 350 KS, but I believe my problem is the factory 305 ESC module! I went through and read many posts regarding the ESC and there really is no definitive answer if it makes a difference or not> I am going to buy one tomorrow, that way it is done and I know that there is no other factor in play here.

You guys think the 305 esc would cause these issues?

 

When I swapped the 305 to the 350 filter, more knocks actually started showing up. I had plenty of spark pulled to make sure I wasn't getting into detonation before I had the right knock sensor, and then when I got the 350 knock sensor, it was reading a TON of knock counts. I couldn't make them go away, so I swapped to Orr's spark table, which added quite a bit of spark, and then started adding in a bunch of AE fueling, and now my knock counts are more in check.
FYI, my knock counts occurred on acceleration from cruise, if I held it at about 1/3 throttle, and also, if I was mean to the car and went straight from decel to AE it would register quite a bit of knock.

 

My symptoms sound similar, part throttle or tip in with a little load, and/or hammer down!

I also get silly numbers; 5-20 on start up, that alone makes me wonder.
Either way, I will be picking up the new esc, its in my head now.

I will be looking more into the AE tables this week, played around a little last week but I was starting to change too many things too quickly and it went sour. I went back to a stock rather stock base tune I have and started to build it up slowly again, it is going much better now!

I read the link you sent me regarding the AE changes , just trying to understand how it all interrelates!

How is you tune coming along now?

 

I never got more than 1 or 2 knocks when I snapped the throttle open. I think that may be due to my PE coming in sooner than yours is.

I haven't done any work on my tune this past week. Last weekend I saw a cop while I was driving the TA, and that kinda scared me off it for a while. I don't have plates or insurance yet. With the aging population on my street, I wouldn't be surprised if the cops have gotten a few calls about my car from the noise and sometimes driving at 80+ mph!

I still need to make some big changes to AE, I'm still seeing that lean spot before PE takes over and goes pig rich. I suppose the thing to do would make bigger and bigger changes at all areas of the table, and then once I have a too much fuel on AE, I'll know I went too far! I can't do that with PE though, I really don't want it going lean at WOT. Little changes will be made in the PE table, if it means I have to burn 30 more chips.

 

Take a look in here if you haven't already, I never thought of this stuff: https://www.thirdgen.org/forums/diy-...gn-iii-pw.html

Makes sense that a totally different injector design would have totally different flow characteristics at different battery voltages.

 

thanks for pointing me there, in all my searches I have not come across that thread. I really think you onto something with the pw and battery voltages.

 

I agree, it should not be pinging or knocking and retarding timing. I believe the 305 ESC may be a cause for that. I have read that knock sensors are "tuned" for specific bore sizes and using one sensor on a different bore can sometimes change sensitivity. It may be overly sensitive, it may be picking up false vibrations

Heres a tip tho, you almost ALWAYS will see knock counts jump up on startups and when you go WOT from cruise spot. Theres no way around it really from what I've found. Even stock cars see this. Tranny downshifts, converter unlocking on a WOT pedal slam will see knock counts. The thing to look out for is, if the counts continue to grow while your on the throttle. If its happy, it wont retard timing and wont continue to knock.

 

Some very valid points!
I will be picking up a used esc today, and will get out with my current tune to see it there is a noticeable difference.
I was searching for a injector pw/ batt voltage compensation chart for these green giants (42lbs) I think I found one, but I am trying to find out if it is the correct one. I really think getting this figured out will make a big difference.

 

If you had an old battery laying around to try, you can try to get it to put out less voltage than normal and tune for that. Possibly disconnect the alternator feed line to the battery and go for a short drive and drain your battery down so it reads 8-11 volts and watch what your air fuel ratio does, and keep adjusting the voltage tables as necessary. You will need a battery charger Basically how i did my car but since my alternator was weak to begin with, with all my accessories powered on, I was seeing like 10 volts anyway so i didnt have to disconnect the feed line. I just played with the offset tables til I had the same air fuel at all voltages. That cured most of my surging at idle when you turn both fans on and the headlights...the voltage dip caused rich/lean conditions and idle went haywire. Now its a smooth transition.

 

That sounds like a pain in the @ss if you have a healthy charging system! I'd contact the vendor you got your injectors from, and have them supply you with flow charts. Get ahold of southbay or FIC and see if they can provide that data.

I'll be ordering bosch III's at some point in the near future, so hopefully you'll have this all figured out by then, so you can help me out

 

Lol, I am sure we will!
I didn't have any time to really tweak the tables today, but I did install the 350 esc and went for a small spin with the boy, So far i am getting more knock counts!
I am going to ask my injector dealer if there is any recommended compensation values that he would know of, if not, I will just start playing with the table a little and see what happens.
As an expirement ,I gave the pw/batt voltage table it a very small move while in the driveway today and the idle tone/change was very noticable.
I shall play again tomorrow!

 

I am still battling timing pull.
I have talked to a couple guys who really think that I am getting false knock counts due to my forged pistons and headers! I still have to insure no other sources of rattling, such as headers or accessories, but it is petty quite in there and i dont think that is the issue.
Not sure what to do at this point, besides the fact that i will be working with a tuner to finish the tune off. I need someone the 'really' knows how to read plugs and the tuning software to help me.
I may need to turn the sensor off,or at least try to reduce the sensitivity.

For now, I have exhaust to finish, and than I am ready for the final tuning/ dyno pulls!

 

You might just try limiting the knock spark retard in the areas where you're getting knock counts. Mine is pulling the full 8 degrees after just a few knocks, I'm gonna try limiting it to 3-4*
My car is counting the most knocks at upshifts lately, so its really annoying to have that much spark being pulled, and seeing it not decay out until I'm half way to the next gear!

 

I know, once the knock starts it takes a good while to settle off.
Where is the spark retard/decay table, or is there one? Cant seem to find it right now, but am certain i remember seeing it.
I may limit my knock retard max down to 2-3* and see what it does.

What is your full advance at now?

My timing table is very conservative overall, I have full load starting in around 17* and tops out at 27. Mid range and cruising timing is at 29-32, and the motor is very happy there.
I am not going to do anymore work to it until exhaust is done, its fruitless at the moment. I should have it done this week, but SHOULD have had it done monthes ago!
I hope have it complete before the end of July! Some friendly competition is brewing........ Shelby gt 500, modded firehawk, z06, they all want my ****!

 

I see... the esc attack rate, and recovery rate. I would think the recovery rate is like a 'decay factor'?

 

That would be my guess.
Also look at the two maximum knock retard tables, one for PE mode, and one when not in PE

I'm seeing my spark advance at 32* all in by 3800 rpm, due to the knock retard.

 

I am going to take a closer look today.

 

I just came across your thread, and not to hijack, I have the same issue with knock counts you're having, I'm running forged pistons also (383). I posted about it a month ago, knock counts are crazy all over the place, I could not hear any knock but was receiving a lot of count's and retard. I ran race fuel in it with a full gallon of Torco mix to 20 gallons- my octane was running at 110+ and I retarded timing way back, still recorded knocks the same. Spark plugs looked good not specs or signs of DET. Came to conclusion false knock indeed. Either forged pistons, timing chain, or Roller Rockers. I'm working on a solution to run a cap and coil to isolate (remove) the frequency the knock is being registered at. Initially I thought my DCR was too high. Here's a pic of my false counts, pulling 8 degrees of timing.

 

No problem , your not jacking.


I may desensitize mine by pulling it away from the block. The problem is insuring that there is no knock, and still being close enough to work when needed.
My forged pistons, and headers may be the cause atm.
Like you, I have not heard a single ping.

 

Pull some plugs and check them for signs of detonation. If none then look for something that will cause false knock. Items such as loose accessory bolts, cracked bracket, exhaust rattle, bad accessory bearing, will all cause false knock.

Note that it is normal to get counts from cranking the engine over. The starter engaging the flywheel/flexplate makes a lot of noise.

The injector compensation data sheet for the Green Giants is on the Muscle Motors web site.

RBob.

 

Thanks for the reply Rbob.
I have gone over everything once to insure no rattling, not to say I missed anything, But I will go over it again!

I keep checking plugs, so far showing rich conditions, black base ring, proclein is bone white but the plugs are very new, so i am not worried.
I do see a very few black speckles, not sure if that would be a definite sign for pre-ignition or not?

I am waiting on exhaust before i continue with tuning. Mid next week is exhaust, week after is final tune on the dyno. During the interm, i will need to get a good baseline tune so we dont kill the whole day on the machine $$$$$$$ !

Thanks for the link, i really want the correct injector pw before anything.

 

The bone white porcelain is normal for an EFI engine running in closed loop a lot.

Note that pre-ignition is different then detonation. Pre-ignition occurs prior to the spark plug being fired. And will destroy an engine in seconds.

Detonation occurs after the spark plug fires, and rattles an engine. Over time this takes it's toll and the engine fails (bearings beat out, head gaskets pushed out, pistons cracked...)

The black speckles is a sign of detonation. They are probably very few as the knock sensor is quickly picking it up and the ECM pulls timing.

RBob.

 

Bad terminology! sorry, I do understand the difference.
I do have a few specks , some plugs yes, some no.
I think the plugs are 'reading' rich due to the last running seconds of the car which tend to be backing it into the garage, I have it idling a little rich atm.
The lean areas, and my detonation are most likely from the typical lean tipin , and heavy off line throttle hits, at least that is what the WB is telling me.
I am working on bringing my Ae in earlier, and longer to see if it helps.

 

So.. I got the offset numbers from the sit RBob sent me too. thx..

How does the ecm use the usec values in the bin file?

Am I adding the new value to my current value, ei;

original value in stock arap6e bin at 12.8 volts is 671.40.
Bosch offset value at 12volts is 0.919

My new value if offset is added would be: 671.40+ 0.919= 672.32
Does this make sense?

Also, in the factory bin, there is a large range from 11.2v -14.4 v, this is the general operating range of the car, should i even it out some and try to make the range a little tighter?

 

Some good ihfo here

 

is the bosch offset valve suppose to be 919, is it in a different unit?

 

Well, not sure, What I wanted to find out is.... to what 'value' or figure does the ecm add the pw correction to?

the bosch numbers in the op range are 11v- 1.095; 12v- 0.919, 13v-0.0786.
I do not know where and what the bosch numbers refer to, or what rule they follow! maybe RBob wiil let us know.

 

I've been loking at the Phormula ks-4 knock analyzer. Looks like the best aftermarket knock data logger / analyzer , uses a Bosch wideband knock sensor. It's expensive but seems to be the only real solution to determine true false knock other than reading plugs.

 

[quote=JDUBB;4967287]I've been loking at the Phormula ks-4 knock analyzer. Looks like the best aftermarket knock data logger / analyzer , uses a Bosch wideband knock sensor. It's expensive but seems to be the only real solution to determine true false knock other than reading plugs.

I took a quick look at it, but how does it filter false knocks?

 

Looks to me like the bin uses msec, and the table you found is in seconds. So the value at 12v should be 919.0msec in your bin? Remember, you have to fit a curve to that table and interpolate for the different voltage values. I'd think 12 to 12.4v is a big enough difference to cause a significant error in the BPW calc.

 

The data sheet offset values are in msec, so at 12V it is an offset of 0.919 msec, or 919 usec.

> original value in stock arap6e bin at 12.8 volts is 671.40.

With this, the XDF you are using is set up to use usec. So you would enter 919 at 12V, if there was a 12V entry.

Also note that the low slope has a higher flow then the high slope. So zero out the small PW compensation table.

What fuel pressure are you running (vacuum line off)?

I'll crunch the data to fit the GM tables for the fuel pressure being run. Some have been able to get Excel to do this, I just have another program for it.

RBob.

 

I was doing a data crunch for other injectors and did the skinny greens at 44 psi. Here is the data:

Injector Data Sheet: 280 155 968, 42 #/hr Skinny Greens

Fuel Pressure: 44
Flow rate: 45.0 #/hr

Minimum PW @ 44 psi: 1.173 msec

Offset Compensation versus Battery Voltage:
6.4 Volts: 4285 usec
8.0 Volts: 2168 usec
9.6 Volts: 1465 usec
11.2 Volts: 1096 usec
12.8 Volts: 839 usec
14.4 Volts: 655 usec
15.0 Volts: 596 usec

Short PW Compensation versus Pulse Width:
0.015 msec: -118 usec
0.244 msec: -101 usec
0.488 msec: -82 usec
0.732 msec: -64 usec
0.976 msec: -46 usec
1.220 msec: -27 usec
1.460 msec: -10 usec
1.708 msec: 0 usec
1.950 msec: 0 usec
2.197 msec: 0 usec
2.440 msec: 0 usec
2.685 msec: 0 usec
2.929 msec: 0 usec
3.170 msec: 0 usec
3.410 msec: 0 usec
3.660 msec: 0 usec
3.900 msec: 0 usec

Note that the small PW table can't have negative values so just zero it out.

For 16.0 volts and 17.6 volts on the offset table, use the graph in TP and extrapolate a smooth curve.

RBob.

 

Wow, thanks for the info. That should save me some unneeded stress!

I will try to work with what you gave me.

The 'Short PW Compensation versus Pulse width' you mention, is this a different table that i am missing? Or you simply mean the rows in my bin at the low voltage area such 0.0- 6.4v.

Appreciate the help, i am sure it will help many others as well