WhiteHawk

I am helping out my buddies in a fullsize chevy forum ColoradoK5.com. Heres my copy pasted article. I thank Thirdgen.org


Software used...Winaldl and TunerProRT
ECM...8746 or 7747 (similar to 8746)

My friend is winaldl, it logs data. I don't really use the data logging feature but I always record just in case. If you are doing WOT tuning, then use the datalogging feature to check your O2 status and when you start knockin. (Hint, the log is in text file form and you will have to adjust the top row to correlate with the columns, just do it you'll see).

Still in winaldl, I use the BLM chart for fueling, once your car gets into closed loop the BLM chart will start to log. I use the wide average feature to see where I am at while driving. Wide average will give you a broader realm of your driving style, narrow will toss the outliers. Get in a nice long drive while running winaldl and when you are done your BLM chart will be filled with numbers. The best number, the one you aim for, is 128 (+/- 4 ok). At 128 your vehicle is running at perfect A/F ratio for the conditions. If your BLMs at a certain MAP are below 128, then you are running rich, if they are above you are lean.

BLM vs. Integrator. The INT is just like a mini BLM, lets say you run lean. Your INT will raise trying to add fuel, once the INT reaches above 150, the BLM raises one digit to 129. Still lean? The INT raises until it reaches above 150, then the BLM raises one digit to 130...AND SO ON. Same with if you are rich, the BLMs just goes down.

How you adjust your BLMs: After you drive your car for a while and get some good BLM numbers in, go ahead and save the table, click okay for the name (has date and time as the digits). Open up the BLM text file (be sure to delete /map so the maps values line up with the columns). Scroll down to the bottom and you will see correction factors. You use these numbers to multiply with the Main VE fuel table in TunerProRT (TPRT).

So you are now in TPRT, you will have to load an .XDF file for the 7747 ECM (if you have that ECM). You can download these off the net, like at moates.net and diy-efi.org. The xdf file is like a template for the bin. A bin is what is programmed on the actual EPROM. Once your xdf is loaded, load your bin. I have found very small differences with "stock" bins downloaded off the net, but this is due to different engines, axle ratios, etc. I recommend using your EPROM programmer to read and save the bin from your stock chip (2732 chip). If you open the spark table (SA) and the main VE table the graphs should be relatively conforming (no right angles and crazy jumps).

Back to tuning, do not touch the SA table until your fueling is done. Take the correction factor values from the winaldl BLM chart and just simply multiply that number to the correlating value in the Main VE table in TPRT. EXAMPLE: if you are running rich, then at 1800 rpms/60 map, its value on the winaldl chart is .865. You multiply .865 to the value on the Main VE table plus Adder VE table value in TPRT at 1800 rpms/60 map. Lets say that value is 60 on the main at 1800 rpms /60 map and at 1800 rpms its 15 on the adder table, so, (60+15)x.865 = 64.9, then 64.9 - 15 = 49.9 <- new value. Easy huh? Go out again driving and make more adjustments until you are close to 128 all over.

This is what I did to my two VE tables. I took the adder table and made all of the values 20. You aren't supposed to zero out the adder because of some compensation the computer does. For example, the adder table at 800 RPMs the value is 14.57, you make that 20, since you added fuel you must subtract 4.43 that from the whole 800 row of the Main VE table. Lets say at 1600 RPMs the value is 26.30 and you make it 20, you would have to then add 6.30 to the whole 1600 row in the main table because you took fuel away from the Adder. The adder table values are always added to the main. Other people have done this too.

Now SA tables, I am about to start on that so I don't really have a lot of experience. If you are getting knocks at a certain area, then you should definatly drop a couple degrees around that area. By getting knocks doesn't mean 5 or 6, like 30-100. You do get false knocks. Like at 400 RPMs and 100 MAP i can get over 300 knocks, but that is probably from the starter or the headers. So tuning the SA tables is really the most SA before knockin.

Edit: I don't know much about the spark bias factors, and basically I just eliminated the main, coolant, and TCC bias by zeroing them out. Surprisingly my car ran a lot better. My spark table is basically a mechanical table (like weights and vacuum advancing). At lower RPMs and low loads the engine has over 40 degrees of advance. At idle I made it around 12 degrees, and it seems to like that. For the WOT you want all of your advance in at 3200 (32 degrees give or take depends on engine). It is also recommended that at lower rpms the advance raises quickly and tapers almost flat from like 1500-3200. There is also slope SA, this is just a degree adder for when you get past 3200. You should make it 0 or play around with it (1-2) for higher RPM advance if your engine likes it.

Another note, using TunerProRT. When you program your upgraded chips (29C256), you will have to program it so it thinks its the old style chip with less memory. It is called stacking. So after you have saved your bin, you will then hit F5 in TPRT. This will bring up the stacking tool. Your bin is 4k, and the chips are 16k I believe. Click browse on the lower input file and pick your bin. Edit the output file with the same name but OFFSET infront of it so you know thats the one you will program. Note you cannot reopen an offset file in TPRT (or I don't know how) so I save both bins.

Don't be afraid of playing with stuff, just be sure to keep track of the good bins.

Also, buy a new 02, since the fueling is all based on the O2. An A/F guage is handy to watch the O2 pinging and also for WOT tuning so you can get off the gas if you're lean.

If you removed EGR, then make sure you change the on temps and speed to real high numbers so it will never turn on.

JPrevost

First off, your article needs some help. First off, which ecm is it (or is it a pcm)? You say 8746 then 7747, they're not compatible.
Then there's the whole correcting the VE with BLM data. First off, both the 8746 and 7747 use 2 tables to come up with a complete "main" VE. The first is usually called the main but it isn't complete. The 2nd table is an adder. You need to add them together and THEN apply the BLM correction factor. Order of operations; Add tables together, multiply with correction factory, subtract 2nd VE adder table to get a new "main" VE.
As for the SA, you need to adjust things according to real world. Things like the base timing should match up in the chip. It's imparitive that it does this. Also, if things like EGR are removed that too changes the SA tables by a significant degree.
And the last thing, the differences between the bin's you've downloaded isn't given enough credit. They might only have a few things different between the 2... in the defined calibration files (TunerPro) but there can be some majorly different data behind the scene's so to speak. There are over 16 defined items different between fed and cali TBI auto f-body bins. Change the rear gears, trans, displacement, year, EGR type, relay polarity, etc. and things can get really confusing. It's good advice to start with what works but it's also better to start with something that's closer to what it is now. Example; don't start with a 305 bin when you've got a 350, same with the rear gears and overall vehicle weight (HD bins vs standard duty or even car bins).

WhiteHawk

I am still a novice in tuning, but what I have done so far has made improvements by the methods I have been using. As for the fuel tables, I took all of the adder values and made them 20 and while adjusting the correlating RPM values on the main table. I have been getting real close to 128 by just multiplying it to the main, but I can see how things go amiss by over compensating without adding my 20 to the main values. I will have to make some adjustments to my article.

Thank you for the critique

BTW, doesn't PCM standfor Powertrain Control Module, thats why I assumed they are called PCMs.

Mangus

I'll just say "good job" and dispense with the criticism. Keep at it!

yager

Thanks for the quick guide and the correction. Im still learning this so every bit helps. Especially specifics on the 8646..

-mike

WhiteHawk

8746...

JPrevost

First off... lol, Just kidding. Can you tell I was rushed when I was typing my last reply? I said "First off" what, 3 times in the first 2 sentances. Sorry about that. It was a time crunch issue on my end.
Good job and PCM does stand for Powertrain Control Module where as ECM stands for Engine Control Module... what part of your "powertrain" is controlled by the 7747/8746? The TCC, so yes, it could be considered a PCM but it's not because of how much it does control. Most PCM's have the ability and code to control the transmissions internal major functions. Where as a dead ecm won't effect how the transmission and rest of the powertrain functions.