Okay here is the deal..
I am a newbie, and starting my tune with the stock ANHT bin.
I have all the required equipment to log, scan, emulate, and burn. I am using Datamaster to log, RTTunerPro to edit and have yet to try emulation. I also just got my wideband O2 LM-1 yesterday. I was working on the lower VE tables w/o PE, ie starting at idle and stepping the throttle up to about 1800 rpms while in the driveway. I would then verify just cruising around in drive and loading the engine as little as possible.
I would like to know what initial changes I should make to the chip, I have already set the injector constant at 26 lbs per a formula to convert the SVO to my GM fuel rail pressures I found in a search here. I would like to turn off the EGR, AIR, stuff like that as I have headers. The information I have found seems to be a bit conflicting as to what I actually need to change to accomplish this. Also what are good turn on/off settings for both the fans? I am getting some hunting in the middle rpms which I believe is from the AIR/EGR reducing the Injector PW by 100ms when htey are requested, from what I understand.

My set up is the following:
350 ci ZZ4 Crate Motor
1.6 roller rockers
LT4 Hotcam
Siamesed and Ported Superram and SR Base
52MM Ported TB
Hooker LT 2151 headers
Automatic w/stall at 2200-2400
Rail Fuel pressure is about 48psi gauge
24lb SVO Injectors
180 Tstat
All the basic and free mods

Any changes I need to make in other areas that stick out please let me know, and a link to the info or some instruction would help. I have been reading here and on TGO, I think my Lower VE is inline, gonna check with the WBO2 this weekend weather permitting. Next I plan on working the upper VE. I am getting knock at 70+ underload, enough to set a Code 43 (ESC) Fault.

Thanks,
Doug

ps: Anyone using the LM-1, how did you hook it up and get the wires into the cockpit?

 

I run a 180 T-stat as well, set my fan to come on at 200 and off at 190. Cruising it temp stays around 180, fans only come on in traffic or at a light.

I still have EGR etc so I have not touched those.

 

bump

 

Um, I thought I gave you the references the other week. If not, try these:

1. Here is a graphic of what a spark & fuel table CAN look like after an
engine is tuned for a new cam & intake in 8D. Maybe this will help illustrate the
difference of a "stock" chip from a fully "modified" chip. That is, one intended
to drive well in all RPM ranges, not just WOT:
http://www.corvetteforum.net/c4/doctorj/cartest.htm

Some details of objective test methods and tools are included in the
write-up. Accurately measuring variables keeps guesswork and unsupported
opinion out of the results.


2. Step-by-Step Instructions for VE tuning are here:
http://www.thirdgen.org/techbb2/show...threadid=39254

The more the cam/ heads /intake vary from stock, the more the air flow changes;
thus the further the engine will be from liking stock fuel and spark maps, and the
more changes to the stock tables you need to make. Start out at low loads and
work your way up. The fuel map will end up as a fairly 'smooth' shape - if you
find you are creating a map with a lot of jagged edges, something is wrong -
ask for more help then.

3. Generally, a larger cam wants more spark and less fuel at low RPM, and the exact
opposite at high RPM. The precise details of your combination you need to work
out for yourself. Once the main fuel tables are roughed-in (so you are not too lean
nor too rich anywhere in the normal driving range) relax. Getting the tune 'perfect'
is something you can work on a little at a time - you won't hurt the engine as long
as the fuel is in a reasonable control range.

4. If you are getting knock counts, take out spark until they go away. You can
sort out the spark table AFTER the fuel tables are in working condition.

5. There is no particular need to turn 'off' the AIR, since I don't recall it having
any effect on engine operation. 'EGR' just leans out the mixture at part-throttle
cruise. If you insist on turning it off, reset the diagnostic flags in the ECM switch
tables; raise the 'EGR enable' temperature in the ECM constants table to a high
value.

6. I found the HotCam to be pretty stinky to tune at idle - it has more overlap than
you will find it easy to deal with, IMHO. Give it plenty of spark so it idles well, and
let the fuel run rich - it will work as a daily driver, but your garage isn't going to
smell very good if you run the engine inside. When you get comfortable with tuning
you can come back for more ideas on how to mitigate cam overlap at idle.

HTH, YMMV, etc.

 

I have been reading the info you sent me and thank you! Here is what I am dealing with and am trying to sort out....
I have a surging in the upper ends of the lower VE table, My injector pulse rate is dropping below 1 and I am getting an EGR request and an AIR request. My understanding with the AIR and EGR request is that the injector voltage (I think it was) is scaled back by .100mV to give a smaller fuel shot. Not sure I am exactly right, but I am at school right now and don't have my notes with me.
Could this be the cause of my surge? I am thinking this is, and my bin is still setting EGR codes, so I apparently did not get the EGR shut down with the FLAG. I have seen at least three different methods to turn the AIR diverter and EGR off on the same ECM (730) in my readings here and TGO. That is why I have asked for clarification. Sorry if the answers to my questions seem so obvious, but I am learning this in between studying for finals.

Thanks,
Doug

 

You're welcome, good luck with the finals.

I work with TunerCat - if you have another program, I can't comment on how things are
labeled. In TC diagnostic flags and 'enable' parameters (permissives) are pretty clear.
If you still can't find them, send me an e-mail off line.

1. AIR is air injection into the exhaust pipes, to control how the cat converters burn.
Once you are past start-up, AIR has nothing at all to do with anything the engine is looking
for - at least as far as I have ever determined.

2. You need to do your logging with a fully warmed engine, to keep any start-up events
out of the logs anyway (at least for the initial tuning).

3. The lower VE table runs up to 1600 RPM and from 20-100 kpa. Where is the 'surge'?
Is this something that occurs while driving? Sounds like you are going lean there - but
it's not obvious if this is a VE table problem or a tip-in problem. You need to tune the
steady-state conditions first; then adjust pump-shot later for the best 'feel'. At that RPM
I'd guess you need more VE. Then I'd try adding (or removing) a couple of degrees of
spark and see if that helps - directionally.

4. EGR is enabled when the car is moving above some minimum mph, the CTS is above
some minimum value, and the MAP is in the cruise range. When enabled it has the effect
of reducing the calculated fuel PW ~ a few %. The effect should not be enough to upset
the fuel PID loop more than momentarily.

Have you blocked off the EGR system such that there is no vacuum leak when it is energized?
Another thing that can bedevil low-speed datalogging is the CCP system. You may want to
verify that is not leaking air into the manifold; or temporarily block the CCP inlet at the TB
to eliminate that variable while you work on the 'surge'.

You need to solve all the mechanical issues before the ECM can do its job - then it's ready
to be fine-tuned.

HTH

 

Thanks for the luck!
Lets see, I am using RTTunerPro, I will take a look at TunerCat.
I will double check what I was reading about the AIR, I am thinking it was similar to the EGR to give a lean out into the Converter for NOx.
I have been logging from turn on so I will stop that. I wasn't really paying much attention to anything other than the transition from open/closed loop.
I have been doing my tuning/logging static in the driveway. I use a folded matchbook cover to step the RPM's almost perfectly 100rpm per fold! The surging starts at the top of the LowerVE around 1300 or 1400, and continues into the upper. The last log I do at the end of the day I cruize around to check the behavior under load. I have been doing this to determine my future plan of action.
EGR: My headers have all the connections to LOOK as if they are smog compliant, but apparently you have to drill out the holes in the tubes for it to actually function. Maybe I should put an EGR plate on my intake to be sure. When I get the EGR request, my injectors are dropping below 1. So I need to turn off the PW subtractor, I will look into this and see what I can find. Even with the EGR off, the request is still generated by the computer, and this must be where I am losing my injector PW.
Anyway, I have my last regular statistics test tomorrow, I need to get back to the books. Nail this one and I may get out of taking the Final, ALways a good thing!

Thanks Again,
Doug

 

OK, I have it now.

Nix the 'idle in the driveway' testing. Idle spark and fuel are separate from the 'real' tables,
and revving the engine in neutral doesn't produce any useful data. You need to tune the
parts of the tables where the car is going to be driven. Try it this way:

Warm up the car, then find an EMPTY road & start the log. Drive it in first gear for a few minutes:
hold the accelerator steady at 20,30, 40 mph for a minute or so each (or something like that).
Then do it again in 2nd & 3rd gear. Better yet, drive up a long hill repeating the same tests.

You want to get logs of the car moving, at different STEADY loads (MAP) and RPMs. The TPS
must be >5%, the speed >20 mph.

Take the logs home and use DM to graph MAP, RPM, BLM, and TPS. You only need to see
the parts of the chart where the values are steady. Then take the BLMs that are <120 /
>135 and pick out at what MAP & RPM they occurred. Make a list. In your program editor,
begin changing the VE value up or down for the points you have found, in the VE tables.

Only change the points for which you have real log data.

Look at the knock counts too, and start to scrub out some spark anywhere you see a bunch
of knock.

Save the list(s) of which points were changed.

Burn the revised tables to a chip, and go back and test drive some more. You need to log as
many different points as possible in the VE tables - from idling in traffic to steady speeds as
high as you can manage safely. This is how to rough-in the fuel tables. After several
repetitions, your logs will begin to show BLMs that stay in the 128ish neighborhood.

Then go find some data points that haven't been logged yet - this is where the hill comes in
handy. DON'T use points where the accelerator pedal (TPS) is changing, or where PE is
invoked. Those points will take care of themselves later.

BTW, as you get toward higher loads & speeds you will need to disable PE, so you are only
measuring the base VE fuel - that needs to be done VERY gently!

After you have a lot of points in one part of the VE table verified, you can begin to 'smooth'
out the points in between. Don't worry about points where you can't drive - like 2,000 RPM
in neutral. You want to know what the VE should be when the engine is under load - the
more data points you gather, the more accurate the fuel map will be.

Keep iterating the test-and-burn process until you have the tables nailed for as many data
points as you can get to. Once the base fuel is right, the rest (WOT) falls out by itself almost.

Try it that way (gently) and then ask more questions as needed. Good luck & have fun.

DrJ

 

Thanks, this makes sense! I guess this may be why I have been having so much trouble working the lowerVE table!
I will use your suggestions this weekend weather permitting...

Thanks,
Doug

 

Well, if my suggestions don't work your purchase price will be cheerfully refunded.

I don't want to be a pest, but you were asking elswhere about pulling a large
plug through a small hole for your new WB.

In my experience, automotive connectors these days are generally modular in
nature.

That means you can pull the wires/connectors out of the plastic plug body. All it
usually takes is a magnifying glass, a fine pick, and a little creative cussing.

Once the wires are out, you can pull them through a small hole and insert them
back in the connector body on the OTHER side of the hole. Just a thought.

DrJ

 

I was looking at the plug that Innovate uses on the end of the O2 sensor and it is different, it is not a typical type plug. The thing is freaking huge for the few wires running through it. It is not like a weatherpack. Since I just bought it, I figured I would ask around a bit before I go to tearing things up! I will post a pic of it when I get home.

DrJ, You could never be a pest, I thought I was the pest
I seriously do appreciate your time and advice!

THanks,
Doug