dimented24x7

iTrader: (2)

96LT4c4,

Heres what Ive found so far for the $0D. Most of whats being discussed here also applies to the later TBI stuff.

EDIT: Hac header info totally FUBAR. Correct version uploaded.

dimented24x7

iTrader: (2)

Just saw that the new VBulletin handles zip files, so you can just zip the bins up and post them. In theory, they should be reconstituted as bins when you unzip the file after downloading.

xjcamaro89

OK, I know BMmonte is racing today and tommorow is Easter, but I did some acceleration runs, I think I did them right. Take a look at them and see what we need to change. I didnt get to do any WOT stuff. At least I dont think I did. I was going to but something went wrong with my computer while logging on the way back from the acceleration run, so I shut the computer down, and good thing to because right where I was going to open up for WOT readings a state cop was sitting watching me, so that save me from a guarrenteed ticket and probably a hefty one at that,
so let me know if the log and reading are ok or if i need to do something different, thanks!

xjcamaro89

rest of files

BMmonteSS

XJ, your log looks good. Your PW is in the log, and I threw it in excel and crunched some numbers the highest you ever got was 70% at 3500 RPM. So you’ll probably have plenty of room by torque peak (highest VE point) which might be around 3500 rpm. Your log rarely goes over 3200 rpm, we’re interested in the 3200-4000 rpm range. From the little bit of data that you got I can see that we are a little rich. I would hold off on changing your VE until you can get a better log.

Also take a look at the picture I attached, you can see where I added columns and calculated your PW and your duty cycle %. Also in the frame I posted you can see your TPS was at 91% and your BLM was locked at 128 so you were in PE mode there. Just keep that in mind when you’re logging. These 128’s can throw off your BLM tables.

Now that we know we are most likely safely rich, we can try to dial in some more timing. More after lunch.

xjcamaro89

How and what am i looking for when trying to stay out of PE mode? I dont know when im in it, also do I need to to another log then, and try to get some numbers up over 3200 RPM, its kind of tricky to run high RPMs and stay out of PE mode. Do I need to make slow acceleration or fast acceleration? Thanks!

DM91RS

xj have you reset the table........(TPS Threshold Vs. RPM for P.E. Mode).....to a higher percentage to stay out of PE so you can log in the higher areas?

You will still need a steady foot to not add any pump shot to the mix

BMmonteSS

On the last bin I posted I set the PE enable to 80% throttle. You can get some steady state readings at higher rpm's. Just down shift to 3rd at highway speeds and cruise there for a bit, this should fill the table in right in the meat of where we are interested in.

Also go ahead and make a full throttle run through 2nd or 3rd and take it clear to 5 grand. We can then see what our Duty cylces look like.

xjcamaro89

I dont feel safe running my car through 5 grand, i have never done it and im lucky if I hit 4000-4500 RPM. So anyway I will do another run tonight and get some higher readings. Then after i get some higher readings what am i going to do with them? Do I make adjustments to my VE tables like I did before? but to only the higher KPA numbers? I want to start making adjustments if possible tonight I have lots of time this evening and with the nice weather I want to take advantage of it. Let me know , thanks!

xjcamaro89

Or do I log a run like i would normally except running some high RPM also, then make changes to the whole VE table like I have before , except this time I will have some higher numbers I can work with? I just need to know what i am going to be changing now and how. Car show are creeping up on me. And the drag strip.

xjcamaro89

Ok i ran a run last night to adjust my adder table, I emailed all the stuff to BMmonte and he probably will be posting a reply with the info.

BMmonteSS

Ok looks like you’re rich by 10% or more up top….that’s what I expected. Just need to keep making changes like you have been doing until those blm’s fall into line. Go ahead and subtract the same amount from the rest of the high rpm values that you didn’t get data for from the VE#2 table (make sure you leave the under 3200 area alone).

That’s very interesting that your off idle problems are being caused by your IAC. Most of the time the IAC only causes problems at idle. Without a better description of what is actually happening as you come off idle, the only theory I have is that your IAC is introducing more air per “count” than a factory TB, thus inducing a lean condition as it opens up. There is a constant that adds a certain amount of fuel for each count of IAC opening. This constant might need to be increased to account for the air. Also if you’re just getting the RPM’s jumping up and down off idle then it might be that the IAC is being overactive and chasing it’s tail trying to maintain your desired rpm. If this is the case then you can slow down the rate at which the IAC can move. This helps smooth things out a bit. Exactly how does the car act off idle??

In the mean time, if you’re comfortable with how the car runs with it unplugged then just go ahead and unplug it for now until we go back and try to fix it later. Several people have experimented with running without an IAC valve, if it wasn’t for the cold winters here I could get away without it. The IAC routines are one of the places that Rbob spent a lot of time on in his ultimate TBI code.

xjcamaro89

This is what the car does. If im sitting at idle, and it idles fine (with or without IAC connected) and punch the gas (while in neutral, not trying to start to move or anything) the car seems like it is going to die, or if i just tap the gas the increase in RPMs is delayed, could it be that my idle is too low? because it idles right around 600 RPM, or is that fine. Also are you saying that I can leave the IAC disconnected? I usually dont run the car in the winter, or when its really cold anyway. Would leaving it disconnected hurt anything, or could I run into any problems by leaving it disconnected? Thanks! So I need to keep subtracting 5% from the 3600 and above RPMs in the VE#2 table till i get good BLMs? Thanks!

xjcamaro89

What is the constant name that adds fuel per IAC count? Is it "AE-IAC opening additional BPW" If so how much should I increase it by each try to narrow it down. If that is not it, which constant name is it, thanks!

Ronny

iTrader: (1)

i have the same issues. when in neutral and i blip the throttle there seems a delay in the engine responding with increased rpms. i will suggest that may be the inability to flow air as easily as one can flow fuel. throttle blades snap open and lean spike. (maybe EBL can help here??). set my aetps values high enough so that i was over the edge rich. no lean pop just a gurgle as rich then i backed it off till i saw the lean pop and back rich till i saw drivability. i will suggest ae tps is quicker than aemap. on my WB i see the aetps followed by the aemap then it times out and the pe shows up. i suspect the blip when data logged will show lean then ae coming in late. tbi systems have some design limitations IMHO.

xjcamaro89

When you say yout AETPS do you mean the AE-Pumpshot vs TPS in the tables, or do you mean AE-TPS threshold in the constants, what kind of increments did you go by when adjusting? Thanks!

Ronny

iTrader: (1)

i use tunercat so i dont have the threshold? aetps i wanna say is the 0-3-6-9-12 up to 25% of tps movement vs the usec values of fuel. each tune is different. i have large inj's at 18 lbs so my tune is different than yours. i have large intake and head flow #'s relative to a stock setup. so i lose some ae as it falls out at lower rpms. i would use the "stock" tables and increase them 10% at a time till you see a desired result. i think it was once said it is difficult to see the 20-25% tps movement and resultant PS. seems we use the 3-18 area more often? knowing that i think my values are same 18% and above.

xjcamaro89

So that worked for you to overcome that problem, i have been doing that but not too much, and I thought I had it right but here my IAC came unplugged and I think i didnt solve the problem I just Thought it did when the IAC came unplugged, thanks!

Ronny

iTrader: (1)

my car idles at 900 rpms with 7.4L TB completely closed. coolant temp is 185 deg. iac is at 0 steps and commanded as such in constants. idle is steady. check the steps for your iac. zero worked for me. others say allow 10 steps iac at idle. occasionally on a rapid deaccleration to stop rpms drop to 600(enleanment) but the iac will recover the idle and prevent stall.

xjcamaro89

Ok sorry for all the confusion yesterday about my IAC, rookie mistake, my chip wasnt completely seated in the holder when i swapped the last one in, that is why my throttle response was crap, its fine now, but now that I plugged in the IAC my car idles real high for a little bit then drops little by little untill i give it gas then it goes back up again for a little and then slowly drops. i think im going to unplug it, i think that it has been unplugged for a while and hasnt hurt anything, and i liked the way it idled without it anyway.

Ok, as for the VE#2 tables, i cant get the darn car to quit running rich, you did say if im running rich in the high RPMs to subtract a % from those RPMs in the VE#2 table, right? Well when I subtract from it, it seems like I get richer and richer, should I be adding a % instead. Im getting messed up somewhere. Let me know Thanks!

BMmonteSS

Glad you got the off idle stumble figured out, that really didn’t make much sense that the IAC was causing the problem. What your experiencing with the high idle is called the throttle follower. What happens is that when you blip the throttle the IAC opens up quickly “following” the TPS. GM did this for a number of reasons, mostly to keep the engine from clunking against a locked converter or in manual applications it helps with shifting if your RPM’s hang for a second while you shift. Fortunately we know how to drive and a little engine braking is nice, so we can disable the throttle follower. There is a constant called the Max throttle follower steps, just set this to zero or at least limit it to a lower number. This should help to eliminate the problem. There is also an IAC park position constant, this is where the IAC is set when you shut the car off. If you get a huge rpm flare when you start the car and then it cycles down quickly, then you can try lowering this constant. If your RPM’s flare up and stay there, you may need to adjust the IAC steps Vs. Engine Temp table. You can unplug your IAC for now, but I suggest you come back and fiddle with the constants some when you have time.

You probably really are way rich at WOT, remember we almost doubled your fuel pressure, and changed the BPC constant, so your WOT fueling is going to be way off. Also keep in mind that your BLM’s are curtailed to the lower limit of 108, so if you’re richer than that you won’t see it in your logs. I would keep subtracting fuel until you get the BLM’s in the mid 120’s and then call that close enough for now. I want to get into some timing changes before we really nail our VE table, just want to have the fueling in the ball park because it’s easy to fall into the too much timing and too much fuel trap. How much have you subtracted now?

xjcamaro89

In my log that I took yesterday all my high RPM BLMs were 108 or 109, and ive already lowered my VE for the higher RPMs 15% should I go more? How much? Like 30%? I just dont want to take it too far. Thanks and I will fidle with the IAC too, thanks!

BMmonteSS

I would keep going in 5% increments, don't want to go too far too quick. I say you're probably within 10% right now. Just make sure your not moving the throttle too much when your in the 3600 to 4000 rpm range. We don't want the pump shot to be throwing our readings off. Just settle into a steady cruise at those rpm's and see what your BLM's look like. You don't even really have to look at the BLM table, you can just watch the BLM value in winALDL and get an idea of what the avg. value is. Just be carefull about watching the lap top while driving, this is where having some one else drive while you tune is nice.

xjcamaro89

ok , thanks

xjcamaro89

Ok, i got the VE#2 tables pretty good, i had to decrease the VE#2 tables in the 3400 and 4000 RPM sections by 20% and the 4400 and up by 22% (the included BLM table doesnt represent that I made the changes for the 22%, I did it after the run) It runs great, nice acceleration power throughout RPMs (not what I know it can be like, but its good), im still playing with the IAC and its comming along. So my fuel is set. I think we are ready to move on. It feels good to have a car that runs the way it should after 5 years of work trying to get it right. I really appreciate what everyone has done for me so far, and im excited about what is about to come. Ive attached the files below!

Hey BMmonte, i just read a post from you on the 400 Knock sensor, would it be a bad thing to desable mine, would I gain anything from it, like getting rid of false knocks, anything like that or is it just fine the way it is? Just a ?

BMmonteSS

Glad to hear that things are coming along. I see your high RPM blm’s are in the ball park, not great but all we need for now. I suggest we turn the PE enable point back down to something like 40 to 50% this will really help bring the power in as soon as you dip into the throttle. Then we’ll start tweaking with the timing tables. I have a write up ready to go for that.

With regards to the knock sensor, I absolutely wouldn’t disable a perfectly good knock sensor. It can literally save your engine while tuning or if you get a bad tank of gas. On a scale of 1 to 10 audible knock that we can hear is an 8 or 9. The knock sensor picks up knock in the 1-2 range and retards timing way before you could hurt your motor. The stray knock counts you’re getting aren’t even retarding timing. You have to get 2-4 counts at a time to get it to even start retarding timing. You would have to have knock counts in the 20’s and 30’s before I would be worried or even take notice.


P.S. This thread just went international I recieved an e-mail from eager crossfire vette owner looking to tune his TBI setup. Good work guys!!

BMmonteSS

A little tuning theory:

There are few ways to tune your timing tables. One way is to just advance the whole table until you get knock counts and then back off the cells that you get knock in….the problem with this is that very few engines happen to knock at the precise point that they make max power. Some engines knock before max power (high compression) most knock after max power so there is no need to run on the verge of detonation. We need to look at the knock sensor as an indicator that we’ve gone way too far rather than a “just right” indicator. We’re lucky enough to know that most SP heads like between 27-30 degrees of timing at WOT. This is much less than the generally accepted 36* that every car magazine has preached for years. This is for a couple of reasons, the main reason is that SP heads are a much more efficient design. So we can just aim for about 28* deg of timing at wot and that will get us in the ball park. So what to do with the other 91 cells? The truth is that the old butt dyno is going to be the best bet to finding what your motor likes. You can also keep an eye on your BLM’s, if your motor starts wanting more fuel with timing then you’re improving the VE of the motor. This is where you have to start paying attention to how the motor runs, how it sounds, and how it tasts…..really lick the valve cover if it tasts salty you can add a few more degrees of timing. …….. Seriously though this is where data logs will only tell half the story. Fuel mileage and good ole SOTP testing is best here. In general….and I mean generally I aim for 20-25 deg at idle, 40-48 deg at low load cruise and 32-38 at med load cruise. Like I mentioned I aim for around 28* at wot and try to get all the timing in by 3200 RPM. I don’t use the adder tables that add timing in during PE or slope in timing after 3200.

Back to fueling:

Once you get your timing tables where you like them, you can look at your fuel again. Your BLM’s will need some more attention. Also I have noticed that if you are rich on the top end and you have your timing set pretty aggressive, you can lean the top end out till you get knock counts then go back a bit. This is a crude way of telling when you have gone too lean. This doesn’t always work and ideally you would use a WB to tune this, but we don’t always have that luxury. I look at the NB O2 sensor and pay attention to the sound of the motor when I tune WOT. You’ll hear the motor get a bit of a high pitched shreak when you start to get the fuel in the ball park. This is hard to describe, and only experience will help you here. By paying attention to the sound of the motor, the NB O2 sensor and the knock sensor we should be able to get the WOT afr in the ball park and get the motor making power.

Of course the most accurate way to judge your AFR without a WB is to do plug cuts. This is where you run the motor up through RPM range under load and shut the car off as soon as possible (very soon) and pull a plug to see what the porcelin looks like. This is a science within itself and worth doing some research on. I find it very hard to find an area where you can do this safely. Hence the reason I own a WB. When I started tuning with a WB I found out that I was way lean below 4000 RPM (13.0-13.5 AFR) and way rich above 4000 rpm (11-12 afr). So I was in a very big ball park, but there was power to be made with proper AFR.

So you can see that we’re starting to gravitate away from the “do this, this and this” type of tuning and more into the try this and see how it “feels” kind of tuning. This is the best way to tune without the proper tuning equipment. (I.E. WB and dyno) I’m going to attach some timing tables to try. As always use at your own risk.

I'll attach some timing tables after lunch

91RockS

Glad to see this thread now moving into timing optimization. Earlier in this thread BMmonte described how to patch pulsewidth and spark advance into the aldl datastream. I recently got the PW and SA into my logs. Having SA and Knock Counts right next to each other in my datalogs is extermely helpful to see when knock is occurring and how much timing is being retarded. I was actually quite surprised to see how much the timing gets retarded with just one or two knock counts.

BMmonteSS

I guess I never really checked, but I bet the car calibrations retards timing a bit quicker than the truck calibrations I messed with in the 747' ecm. How quickly and how much timing is retarded is completely adjustable. Of course every combo is different and thats exactly why you have tune.

xjcamaro89

OK, i guess im ready for advancing the timing. Am I going to actually advance the timing physically on the car, or is this all going to be done with the tuning? Either way let get to it and see what we come up with. Also BMmonte, you race today? How did you do? Thanks!

Italy84

Yesssssssss!!!

here trying to learn!!!
you guys are fantastic!!!!

BMmonteSS

Sorry for the delay guys...been doing things for the wifey. I'll get the timing tables and bin files posted up when I get back to my other computer tomarrow.

You'll also never guess what the wife talked me into....I've been discussing putting an LS1 into my Monte for a while, she suggested we get the C5 thats connected to the LS1 and be done with it......... .......can't argue with that logic!!!!

xjcamaro89

I wish my fiance was that understanding, i found a tired 85 RS with a 305 4bbl, good body good interior for $1200!, it wouldnt need that much work to get it looking nice, and holy cow, i got the hairy eyeball the rest of the day!

JP86SS

iTrader: (1)

You have the blessing, DO IT !
(before she finds out how much it will cost )

Great thread BTW.

BMmonteSS

Sorry for the delay....couldn't put down the corvette trader Looks like 22K to 26K will get me a nice 40,000 mile coupe with a 6-speed. Back to your regulary scheduled program.

The table I'm going to attach is just something I came up with off the top of my head, I haven't run this in a vehicle before. It's just an example of what a table with 28 deg max timing, 25 deg at idle and around 38-40 deg at light throttle cruise looks like. Feel free to try it out, but keep an eye on your knock counts and see how it runs. The bin file I attached is NOT Xj's most recent bin file. It's just has the timing modifications done to it, just use it as a place to copy your spark values from.

WARNING:
Do not run this timing table without setting your PE spark table to 0 and setting the amount of "spark slope" thats added in after 3600 rpm to 0. If you don't do this you could have way more timing than you want. Every vehicle is different and this is just my best guess as to what most LO3's would like. Try it but don't yell at me if your motor doesn't like it.

BMmonteSS

Bin File

xjcamaro89

Can i start off with half of that advancing and see what happens, i would rather start with less and work my way up to more to see what it likes. How would i adjust the tables to only allow half the the advancing that you put in it? And what am I really looking for when running, and how would i make adjustments to what I get in WINALDL. Thanks, i want to run it tonight. Let me know!

xjcamaro89

Anyone can chime in here, if i want to start off with half of the spark advance that BMmonte set up in the last bin, can i just cut the values in the SA table by half? Thanks!

RBob

iTrader: (1)

I dropped a note in the other thread: one thing you can do is to take the difference between the original SA tables and the new SA tables, halve the difference and add that to the original SA values. Create a new BIN from that.

That way you are only adding half the amount of timing that the new BIN has.

RBob.

xjcamaro89

Thanks, while i was thinking during my lunch break I thought of that too, thanks again!

BMmonteSS

Thats a good idea, never hurts to go in baby steps. Idealy you want to sneak up on your timing table. I posted this table as more of an example of how to aim for certain values under different conditions and then smooth out the rest of the table.

I think this table is a pretty good guess for what an LO3 would like, what do you more experienced guys think?

91RockS

XJ - If you have advanced you distributor timing (mechanically on the dizzy), you'll need to account for that as well since it will add in that amount universally across the entire table. Either set the dizzy timing back to 0 or set the base timing constant in the bin to the value you've adjusted at the dizzy (hope that makes sense). The spark table BM posted has 28* of spark at 3600 rpm @ WOT. A couple more degress of spark may get you into knock with 87 octane fuel.

BM or others - once a knock event occurs, what constant or table determines how much spark is pulled out, and how long does the timing stay retarded until the ecm reverts back to the main spark table values? On a WOT blast my logs appear as though the timing stays retarded until the throttle is lifted at a gear shift (manual trans).

BMmonteSS

There are some constants and tables that control the attack rate, maximum amount of retard, and the recovery rate at which timing is added back in. I don't have tunerpro on this computer to list the actual table names but they're pretty clearly labeled.

The way it works is that when you get knock counts the ecm starts ramping out timing based on the number and frequency of knock counts (table determines how fast) . It will keep retarding timing as long as it sees knock. Once the knock has stoped it will start ramping timing back in (again a table determines how fast. There really isn't a second timing table like a lot of the later model ecm's use.

Rbob did a great write up about how to use a TBI ecm as a timing only computer. It lays out the entire timing routine very clearly and it's a must read. Gotta hit the sack, I'll see if I can find a link to it later

Fast355

iTrader: (2)

Here is my timing advance table (low-speed), but it stays the same all the way up after 3,200. This is a swirl port equiped 350 with 8.75:1 compression and a mild roller cam with a 109* lobe seperation angle.

xjcamaro89

Ok, i took the SA table that BMmonte gave me with 28* timing and backed off the entire table to half of what he increased it by from a stock SA table. Sorry BM to hack your table, im looking more for a good running car, instead of pushing my car to the limits. (Not saying that, that is what your trying to do) Anyway, i ran a logged run, adjusted my VE #1 table 2 more times and I think I got it running really well, idles good, cruises good, accelerates great, BLMs are a little lean but just by 1-2 BLMs in some places, which im assuming is fine. It just seems like it is running really smooth and really good. i am posting the info from my last logged run yesterday. Take a look at it, make sure it seems to be running right to you guys. Also where should my O2 be running at? Thanks for all your guys help so far, this is turning out great! Oh I also did a quick WOT acceleration run, its clearly marked, take a look at the LOG, thanks!

91RockS

I took a quick look at your WOT datalog. Looks like you made three separate accelerations from ~ 10 mph to 70-80 mph. You were being pretty gentle on the throttle since TPS never went over about 50%, so you really were not at "WOT". You picked up one or two knock counts and the very beginning of runs 1 and 3, but nothing to worry about. 02 readings look like you're running safely rich. If it were me I'd rachet the timing up another notch.

xjcamaro89

Did anyone happen to look at the log that wasnt WOT? Does anything look fine there? I just want to know if it looks fine because right now I am real happy with the way the car is performing, and if the logs dont show anything out of the ordinary, or bad, i might keep it were it is. It pleases me!

alvanwie

xj

Been following along with this thread. Glad you are happy with the results. It appears you are somewhat rich on the WOT log and remember you did not even go into PE since your bin still has PE set to 80% at all rpms. You probably should work on this area some. If you do not wish to make further changes to the spark tables I would at least get PE enable set up properly and then maybe give it a couple of more degrees of timing during PE.

BMmonteSS

XJ,

You most definitely want to lower your PE threshold back down, I like to make mine below 50%, and this really helps with responsiveness. If you have a real heavy vehicle or tall gears you may get into PE mode while cruising, in this case you can raise the threshold a bit.

I think you may be confused, you haven’t posted one log of you going WOT. The most I’ve ever seen was 80%, and that was on a log from a while ago. The log labeled WOT pass never went over 50%. We really need to have a good WOT log to make sure your injectors aren’t going static, and that we’re not getting any significant knock counts. With where you have the timing set I don’t think you’ll have any problems. You still have room for improvement with a few more degrees of timing and possibly leaning out your WOT mixture. Now come on, go out there and open her up and see what she’s got!

I like fast355’s timing table, his vehicle is a bit heavier than a 3rd gen so his table is a bit more relaxed than the one I posted. I think his table would be a good one to start from and possibly try a few more degrees of timing in places and see how your car reacts.

xjcamaro89

Im sorry!!!! jk I thought I was at WOT, i didnt look at the log enough. but I thought i had my foot to the floor. Also I was wondering. in the SA tables, what kind of increase constitutes for a degree of timing? I will also set my PE down a little farther, i didnt lower it from when we raised it before, thanks! But all the driving information i posted looks close to normal or in the ball park and nothing is out of the ordinary, thanks!