88gunmetalgta

iTrader: (1)

I'm in the process of building a new engine for my '88 305 tpi Trans Am.

The new motor is 383 CI, with AFR 195 heads and a comp cams 503 cam specs here: http://www.compcams.com/Company/CC/c...?csid=196&sb=2
Short version: 276/281 adv. dur. .536/.544 valve lift (w/1.6 rockers).
Intake will most likely be the edelbrock victor e single plane intake manifold with a LS1 TB. I haven't bought air and fuel delivery stuff yet.
I should be right around 500 hp at the crank
transmission is 700r4 with 2500 stall lockup t/c.

Here's why I'm posting:

I plan on using the '165 ecm thats in my car now, although from what I have read, I will need a memcal from a 350 car to retain my knock sensor (which is based on bore size, correct?)
I will be keeping the car MAF for now, unless there's a really good reason to switch to SD right away.

My biggest question is, will the $32b BIN work to start up the new 383, or will I instantly grenade my shiny new engine? I *should* be able to handle changing constants, but if I had to dive into modifying a table I would be completely lost.

I guess what I really want to know is, can a beginner like me start with the factory tunes that are available to me (likely the 350 version of what I already have), and come up with a workable tune for my 383 without damaging it, or am I in way over my head, and should just leave it to the "professionals" to make me a base tune that I can modify and tweak as needed and as I learn more.

I am totally new to engine building, DIY EFI, and DIY PROM burning. I'm heavily counting on support from several different online communities to help me pull this thing together, and so far its going very smoothly.

Sorry for the long read :-/

dimented24x7

iTrader: (2)

Assuming you set the proper injector constant and the MAF flow table is good, you can probably start the car and at least make sure the engine runs ok. You will also probably want to set the idle timimg to around 22-24 degrees so theres sufficient advance to allow the engine to idle. Maybe also raise the desired idle speed as well as setting the min air a little higher so that the IAC doesnt have to supply all the air. On startup, Id imagine that it will probably surge a bit and not run as well as it could with that cam and the stock, or near stock calibration, but I dont think youll do any damage. I wouldnt want to do anything more than part throttle driving with a large engine and a MAF ECM due to the inherent limitations on how much flow it can see. Its possible to get around those limitations, but it requires a late model LS1 MAF and a translator, as well as some adjustments to the ECM.

dimented24x7

iTrader: (2)

Also, another thing you might consider doing, is using the ARAP $6E bin. I think thats compatible with your ECM. That one was meant for use with the alum. headed L98's, and may be a better starting point than the current bin.

88gunmetalgta

iTrader: (1)

Thanks! That's just the info I needed. I'll look into the $6e bin.

Orr89RocZ

iTrader: (20)

Yep, try the ARAP but do these changes:

--Disable EGR by setting MAT < X to max value of 304. Can also go to the EGR cycle duty table and make it all 0.

--Change timing table...ARAP is very aggressive and the new AFR heads do not want or need that high timing. Older style AFR's do well since they are VERY close in design to the L98 aluminums. You can easily look up a different stock bin file for the iron head cars like AUJL or similar and modify it accordingly.
I find it easier to make the PE mode spark advance table all zeros and add those values back into the main table. That way you have 1 table to look at and work from. Makes changes alot easier. If you want I can send you my old 383 bin file as a reference.

--Idle rpm vs coolant... make it 800-850 for now with that cam at warm idle over 140 deg F. Cold starts, I'd try 950-1000 and ramp it down as temp warms up. That cam aint huge so you should beable to start up on ARAP easily and idle really stable.

--Set injector constants to what you are running.

--Set base timing value to the base timing you set the motor at. This is the hard part because you need to fire up the motor with EST disconnected, then set the base timing, then set it in the bin, and reconnect the EST and refire the motor... Once you get the motor running you can dial it all in.

--Maximum Air flow vs RPM table... make all values from about 3200-3600 and up all 255 grams/sec.

Those few changes make a good starter bin. It should start/idle and part throttle drive ok. heavy throttle going into PE mode and WOT stuff will need to be carefully watched.
ARAP seems to run rich with stock settings for alot of setups. I had to remove a good bit of fuel in PE mode on a heads/cam L98.
I had to add alittle bit of fuel here and there with a heads/cam/modded TPI 383 that should be very powerful that had based on ARAP, but you could have ran it with stock bin settings without blowing it up. It would have been lean in spots but workable. Chances are it may have been too rich and I would have had to lean it out but we were working with narrow band o2 values and not a wideband... Either way, I was impressed with how ARAP handled it.

I used AUJL for my 383 and it wasnt close at all with WOT. I had to change fueling alot. Idle and cruise however were pretty good with the minor changes made above.

88gunmetalgta

iTrader: (1)

Good info. Now I have some more research to do. Any input on how the how to keep a knock sensor on my 383?

Also, can I just burn the ARAP bin to my '165 chip? or is there more work to it than that?

Orr89RocZ

iTrader: (20)

If you have the 165 ecm already, you should beable to buy the chip adapter kit from Moates and the blank chips, burn the ARAP bin and plug it in. I'm not 100% sure if you need a 6E based factory memcal/prom assembly or not, as you need the factory prom to mount to the other side of the chip adapter.

But yeah, you should beable to keep a 350 L98 knock sensor just fine and run the 6E mask tunes. Thats what I do for both my 383 and my 400...I just run a knock sensor for the ecm system I'm running...but the 400 doesnt have a specific knock sensor for the bore size.

88gunmetalgta

iTrader: (1)

This post is more for my memory than anything:

From Traxion's tutorial:

So, in order to make the $6E bin work on my chip I need to:

1. Get rid of cold start injector. Easy, my new intake won't have provision for one anyway

2. set fans to "normal operation"

88gunmetalgta

iTrader: (1)

From here on out I'll try to keep my tuning questions consolidated in this thread.

I pulled my ECM last night. The label says AKFS, but I was unable to locate this bin anywhere online, and I don't have the equipment to burn or read PROMs yet. I found an awesome reference stumbling around on the GMECM pages that listed BIN BCC's by application, but I can't seem to find it again. Does anyone have it bookmarked or know where a similar database is?

I downloaded TunerPro last night, and opened up a couple of BINs just to familiarize myself with everything.

Orr, I made all the changes you suggested above in a factory ARAP BIN, and I'll take your offer to let me look over your 383 bin. You weren't kidding about the aggressive SA table!

I simply stole the SA table from a different $32B Bin and copied it into the ARAP table.

I plan on doing the first start and cam break in on my 383 with the chip that's already in the car, so I'll have to try and set initial timing to whatever's in the BIN already, even though I will leave the ESC bypass disconnected for the initial start. Anybody know what that value is in AKFS?

RBob

iTrader: (1)

The initial SA in the BIN will be 6* BTDC.

If you are leaving the EST/BYPASS connector open I would also connect a timing light and leave the distributor a little loose. That is enough to be able to turn it by hand but not have it move on it's own.

Once the engine is started turn the distributor for about 22* BTDC of timing. Can adjust it from there a little more or less to what the engine likes.

Then once the cam is broken in and the engine RPM is at idle, set the timing to 6* BTDC and tighten the clamp. Recheck timing to make sure that it didn't move.

There are a few other changes that should be made to ARAP before using it. The fan control may be inverted, on while cold and off when hot. There is the cranking fuel hold off versus DRP's that should be changed. This is to get the engine to fire right away.

For the fan control, I think this should work to test it: short A & B on the ALDL and key-on, engine-off. In a few seconds the fan should run. Then remove the jumper and the fan should stop. If it does good to go. Otherwise there is an option flag that needs to be changed.

RBob.

RBob

iTrader: (1)

Also, ARAP has VATs enabled. Not sure if your '88 has it or not. If not then be sure to disable the option flag for it. Otherwise the ECM won't fire the injectors.

Rbob.

88gunmetalgta

iTrader: (1)

Yes, I caught that fan flag. I set the bit. Should be correct for my car, it was set in the AKFM $32B bin I opened.

My car does have VATS, but I had to tear apart the steering column. Hopefully it still works, as I said I will attempt to start the car on the unmolested 305 chip first.

I've read about the cranking fuel table, but I couldn't remember what the name of the parameter was. Thanks!

Orr89RocZ

iTrader: (20)

Car is a hydraulic roller correct? if so, there is NO cam break in. Just fire it up, set base timing the best you can and reconnect and let it warm up to let the parts say "hi" to each other. Few heat cycles while you mess with the idle tune and you can start driving it to do the break in.

Did i ever send it to you? I can sent you 2 bins, my old 383 which was AUJL based for 6E and a heads/cam L98 that is ARAP based for 6E.

Really dont need to venture too far from base arap to get it to work. Fan control can be an issue like said. I had my fans on switches and so did my buddy so problem solved there. I guess the flag option will solve it too

88gunmetalgta

iTrader: (1)

I know, I know. Hyd roller's don't require break-in, but some will argue there's still a little bit of an affect it can have. I figure it can't HURT to run it for 15 min or so above 2000 rpm, whether it helps or not, I have no idea lol.

No, you never sent me the files as I previously had no way to open them. I just recently got internet at the house, and downloaded TunerPro.

I'm sure I will be alright with the TPI intake on it, but once I swap over to my Victor E and LS1 components, I'll need to make some big changes to the MAF tables. I'm guessing a good place to start would be to try to work from an LS1 MAF calibration table.

gbayfisher

Are you going to use a wide band sensor, and what knock sensor did you use?

88gunmetalgta

iTrader: (1)

Although I haven't replaced them yet, I will get a 350 KS and ESC module.

I haven't considered using a wideband at this point. I know costs have come down, but it still seems a little cost prohibitive? I haven't looked into it much at all.

gbayfisher

What ESC are you going with?
I would consider a WB.
Seems that you can get o.k drivability without one, but you cannot do wot fueling without. I think it is much safer to use one, imo.

88gunmetalgta

iTrader: (1)

I thought you only had 2 options for ESC modules: 305 and 350.

I'm not sure what all comes into play at WOT. But I thought the LS1 maf and some creative maf table editing could get around that limitation. Doesn't WOT base fueling off MAF input and O2?

Orr89RocZ

iTrader: (20)

I think you'll be wasting your time I dont know anyone doing this on a roller. I'd set it, let it idle, check rocker arm nuts and lifter preload and run it.

Send me your email and i'll send you my files.

I am not sure how the LS1 MAF works in the conversion to our electronics, but if you go LSx throttlebody and keep stock MAF that will be fine, just may need to tune AE tables due to the different throttle body shape

gbayfisher

Sorry, thats what I meant, 305/350.
I am new to this and could not tell you what ALL comes into play at WOT. I am still doing the research in this area myself. It is definitely possible, not sure how difficult without the Wb
Not sure if i will be using it myself just yet.

88gunmetalgta

iTrader: (1)

Well the LS1 MAF is a little ways down the road yet, gotta make sure I have an engine that works first .

I do have a MAF table from an LS1 car that I *should* be able to use as a starting point for the MAF tables. The problem is the 255 gm/sec cap in the $6E mask. Basically, for the MAF tables, I will end up dividing the actual airflow by a factor, than increasing the base pulsewidth by that same factor (I think). However, I think thats gonna end up increasing fuel in every instance where fueling isn't based on airflow. There's a lot I need to learn before I get to that point.

Orr89RocZ

iTrader: (20)

I wouldnt worry about that for now. Just tune based on the stock MAF. You can get alot out of the stock MAF even once it becomes maxed out which usually happens in the mid 4000's rpm range on hot motors. Use PE mode vs rpm after that and make sure you set it to come on around half throttle TPS and LV8 below 70.

Can tune without wideband by watching narrow band o2 voltage but WOT fueling on MAF is primarily just MAF values and PE mode enrichments. Once MAF is maxed, its all PE mode which isnt bad since its vs RPM in 400 rpm increments to 6400 rpm. Very effective way to tune. Fueling generally follows the torque curve. Most fuel is required at peak torque since most airflow is there.

88gunmetalgta

iTrader: (1)

Baby steps! After the first start on $32B, I'll swap over to $6E and my Victor/LS1 TB setup, and tune with the factory MAF until I feel confident enough to dive into the LS1 MAF tuning stuff.

Even with the 305, I had it in the 4000+ range often enough that I definitely want a good, driveable tune in that range for the 383. That's sort of why I want to stay MAF, for the ease of tuning and good streetability in any given atmospheric conditions.

And you tuning gurus all went through the same phase of experimenting with different setups to find out which scheme you prefer, same as I plan on doing

gbayfisher

Its very interesting indeed! I can wait to start messing around with mine!
How exactly do you plan to do the Ls1/Victor?

88gunmetalgta

iTrader: (1)

What part about the LS1/Victor stuff?

The intake manifold bolts on between the cyl heads.......

The LS1 TB should be pretty straightforward, the TPS and IAC just require new harness connectors. And creative throttle and TV cable bracketry.

LS1 MAF outputs a frequency signal, our ECM's need a voltage input. There are a few ways to accomplish this. The one I'm gonna use is an IC that simply scales the frequency to a voltage. Converter output is .85V @ 2.00kHz, 5.0V @ 12.0kHz, or voltage = kHz x .415.

gbayfisher

[quote=88gunmetalgta;4866743]What part about the LS1/Victor stuff?

The intake manifold bolts on between the cyl heads.......

What upper intake/plenum are you using?

88gunmetalgta

iTrader: (1)

Don't know for sure. Something like these:
http://www.summitracing.com/search/Part-Type/Throttle-Body-Intake-Elbows/Intake-Elbow-Mounting-Flange/Square-bore/Throttle-Body-Mounting-Flange-Application/GM-LS1/?Ns=Rank|Asc

88gunmetalgta

iTrader: (1)

Well I got all of my Moates equipment yesterday. I've burned a couple of chips, and I installed the adapter and my new chip, and I got a code 12 from the CEL, the fuel pump primed, and the cooling fan came on with the ALDL jumpered. So it looks like I've successfully burned my first chip!

gbayfisher

Nice!
Have you run it yet?

88gunmetalgta

iTrader: (1)

Nope, my intake manifold is off, and I'm waiting on parts to swap to the victor manifold. Throttle body is on the way, it will be a little bit before I order the fuel stuff though.

88gunmetalgta

iTrader: (1)

I just realized I forgot to change the injector constant in my bin, which raises a couple questions.

I'm running my factory 19# injectors (for now), and I still have my stock fuel pump.

I'm wondering what I should set my fuel pressure at. I prolly won't attempt WOT, but I'd like to be able to tune for cruise and AE.

Also, can someone refresh my memory on how to correct the injector constant for higher fuel pressure? I've come across the formula a million times, but when I need it I can't find it :-/

Orr89RocZ

iTrader: (20)

square root of (new pressure/old pressure) * injector rating@old pressure = injector rating@new pressure.

So thirdgen 19 lbs at lsx 58psi pressure levels would be 22 lbs just about.

88gunmetalgta

iTrader: (1)

So how much pressure do you think my stock pump can handle?

Orr89RocZ

iTrader: (20)

You wont need much fuel for cruise and light/medium part throttle. The pump should handle some pressure but its gonna wear it out faster more than likely.

88gunmetalgta

iTrader: (1)

Well, I got a datalog.

I started it up and set the timing at 10* like it is in my bin, then I started datalogging, just at idle with a little throttle.

I can't quite tell what I'm looking at yet, and after running it for a bit before datalogging, it was already warmed up and wanting to go into closed loop. My fuel pressure is low right now, and I didn't change the injector constant.

I got a little bit of stumbling when I cracked the throttle open, so add some AE fuel, right?

Also, a fan should have come on, but didn't.

I just shut it back off, and i'm posting this from the drivers seat.

The log file is an .xdl renamed to a .txt. is there a better way to upload them?

88gunmetalgta

iTrader: (1)

I disconnected the vac port on my FPR, and that helped make things a little more stable. I burned a new chip, disabled closed loop, changed my injector constant, and a couple other minor changes. Also my base timing was set to 22*! I coulda swore I set it to 10* in the bin.

Needless to say, it was a night and day difference. I'm gonna rig up something for my TV cable tomorrow and start driving it a little bit. I drove about 200 yards today. I thought I got a datalog, but apparently I screwed it up.

Only one odd thing I noticed. O2 mV was pretty steady, but climbed from somewhere in the ~.800's to somewhere in the .900s throughout the second scan.

88gunmetalgta

iTrader: (1)

This morning, I started the car up and did another datalog. a couple hard revs to 4000 rpm, and I got a few knock counts. I was in PE mode, and I should have zeroed out the PE mode spark advance like Orr suggested. I was getting 41 degrees of total spark advance, too much for my AFR heads.

Is it possible to get the AE and PE status to show up in the datastream?

88gunmetalgta

iTrader: (1)

After messing with my car for 9 hours today, I think I'm finally starting to figure out what I'm looking at in the datalogs.

I adjusted the fuel injector constant (by trial and error) to make my BLM's stay pretty much even throughout all of the little trial runs I did.
I don't have a pressure gauge in the instrument panel, so I can't really tell what my pressure holds at throughout the rpm range. I think the injector constant is 1 or 2 lbs/hr higher than the actual constant.

I still can't tell if I have any AE fueling going on, or if I am in PE mode.

The BLM's do sink a little bit in the datalog, seems like its from about 30-60 gms, but can that be attributed to AE, or should I start messing around with the MAF tables?

Also, I do hit PE for a couple seconds, and the O2 mv jumps up instantly. It was at about 2500 RPM, which is the only place where PE vs RPM isn't a negative number. (I was confused and thought high O2 mv meant lean, so I got off the throttle right away)

I think with a few pointers I'll be well on my way to having a good tune

Orr89RocZ

iTrader: (20)

Its best to set injector constant to what injectors would flow at under the pressure you have at the rails, then work MAF to get BLM/INT close to 128. If your telling it you have 21's when you have 19s, you are leaning out the tune. So you can set it at 19 and be prepared to drop MAF tables down.

From your log it looks like you have BLM in the 112-116 range in some spots. Your still gonna need to lean it out more. Appears 45-85 g/sec is rich as well as 115-130 ranges. Since its such a large range, you may try adjusting scalars for tables 1-3 once you set injectors to 19lbs. (unless your fuel pressure is high and the injectors are acting like something else).

You also have 33 deg timing at idle it seems...that may be abit excessive. Usually 26 or so works well but give the motor what it wants. Too much timing can also make a motor run hot.

You did hit PE mode a few times... about the 2400-2600 rpm range, LV8 was over 160's into the 170's at times, about half throttle. You can tell because your commanded Air Fuel ratio changes from 14.7 to 11.7 and the BLM/INT both go to 128 and stay there. O2 milivolts will jump to a set value range instead of switching back and forth. Example, on yours, it goes to about 920 milivolt average...ranges from roughly 900 to 940 milivolts. Seems alittle rich there because of that, as i have found that around 900 mv you have mid high 12's to 1 air fuel and thats a good starting point for power

88gunmetalgta

iTrader: (1)

Question: I keep seeing AE referred to as "Pump Shot", but I'm seeing O2 mv drop AFTER the delta TPS that should have called in AE. ie, tps increases then holds steady, O2 mv drops and stays low for a couple seconds. How long does AE stay in effect? Could my AE be lasting long enough to lean it out?

Ok, well it turns out my fuel pressure gauge needle wasn't shaking because it was a crappy gauge mounted on a shaking engine, but the pressure was actually pulsating.

I had to turn it back down to stock pressure to help it keep up.

I tweaked a couple of MAF scalars, and it seems like they actually edit the values in the tables, instead of being calc'd by the ecm. So the last and first cells no longer match up! In some cases, going from one table to another jumped 14gms! I think its best to stick with the tables, and leave the scalars alone.

gbayfisher

lol, is that why everyone cringes at the thought of messing with the scalers?
I assumed it was a ecm calc and not table changing!

Orr89RocZ

iTrader: (20)

Change the scalar and the table will change. Its a multiplier basically. Just make sure that the "common" values between each table match. Like top entry of table 1 needs to be same as bottom entry of table 2 since they overlap.

I like tables more than scalars, but if you need to make a quick global change, you can do that with the scalar. OR just highlight entire table and use the multiply function in the tool box to increase the values. Its up to you.

But if you ever try to make a larger tube MAF sensor based on stock guts, you will need to adjust the scalars up to allow for you to enter a larger range of numbers into the table. Program seems to have a cap on the value you can enter unless the scalar is large enough.

I never watch o2 values when dealing with AE. I only go by feel. If you mash the gas and the car doesnt hesitate and seems "crisp" on throttle response, you are doing good.
YOu can hesitate from being lean and bog when too rich, so you really need to go by feel. A quick sensing wideband can pick up on AE fueling changes but stock narrow band I'm not sure it can read that fast.

88gunmetalgta

iTrader: (1)

I did a little more experimenting with the scalars today. I hit the ceiling in MAF table two, so I had to adjust the scalar up a notch or two. Other than that, I think I'll do all my editing in the MAF tables themselves.

The MAF tables are finally starting to make sense. In other words, I've gotten them to the point where the BLM's aren't flatlined at 108, or all the way up at 160!

I'm still kinda confused when I see the BLM's drop at one MAF voltage, and then up at the same voltage 5 minutes later!

88gunmetalgta

iTrader: (1)

I swear I only clicked "post" once!

85projectZ28

lotta good info here!

88gunmetalgta

iTrader: (1)

I went for a little drive today, not really paying attention to the computer, but just observing how the car's behaving. I think I need to pull some AE fueling, it sorta feels like a stuck choke would when I step on it a little.

Take a look at the datalog and tell me what you think. I've already made some changes to the MAF tables based on it, I just wanna see if they match up with what you guys would do!

Yes, there is, thanks to all the knowledgeable contributors who've helped me out! I'm basically trying to record all my observations as I go along; I guess you could call it, "A n00b's diary of tuning $6E"

gbayfisher

Where's the log file?

88gunmetalgta

iTrader: (1)

Right here sorry

gbayfisher

How do I view a log file if its a .txt? No idea how to convert it

88gunmetalgta

iTrader: (1)

Download it, rename the file to an .xdl, and open in tunerpro. The board won't let me upload an .xdl