So I recently picked up a built 1991 B4C Third Gen Camaro. I'm extremely happy with the car minus the one tuning issue. I ordered an AutoPROM to see if I could straighten it out. Basically my problem is once I hit PE mode at around 2k-2.5k RPM's it floods the cylinders (9 AFR on my WB), then begins to finally get going after about 3 seconds. So upon reading my stock tune file, I am either reading this absolutely wrong or monkey's tuned this car. Any advice would be helpful.

I am obviously shooting to fix the AFR's throughout my PE. I understand the AFR vs. RPM table equation is as follows...

14.7 (Stoich) / (1 + (% / 100)) = final AFR

Looking at a stock BIN for a 91 AUJP computer, this makes sense with the numbers. Looking at my currently loaded tune, I'm lost and feel like the tuner had no idea what he was doing. I have captured a screenshot of the graph of my current tune versus the stock tune (red line in the picture). Any opinions?

 

You sure its reading the file correctly? That aint right at all

Pe enrich should follow the torque curve. Most ve or airflow occurs at peak trq rpm so you expect go see a slight increase there and then taper off abit then begin to climb with rpm as approach peak hp rpm

After 2400 rpm it should be rapidly leaning out. Does that happen?

 

I'm pretty sure. I took the chip directly out of the G1 adapter, placed into the ZIF autoprom socket. Opened up TunerPro RT, hit initialize and downloaded the BIN. In fact I downloaded it 3 times because I thought the same thing at first. I could be doing something wrong? Any suggestions? Haha.

 

If the tuned chip is a '512 need to read and save the top half to get the BIN.

RBob.

 

Do you have any guidance on how to do that? I'm messing around in the software seeing if I can figure it out, but any help would be amazing. Thank You.

 

I believe I may have fixed my issue. Under the Tools (Moates PROM Read/Write) I selected the chip and changed the Start address of the chip to 8000 instead of 0000. The buffer address wasn't touched and remains at Start (0000) and End (7FFF). After using these changes, I got a somewhat better AFR graph with only a maximum deviation of 6 percent. On top of that though, I was able to see my injector flow rate is set at 22 lbs/hr while I'm running 30 lb injectors... Guessing that might be a good reason I'm running a tad bit rich.

 

Tuner Pro can compare two BINs and display the differences. Great tool.

RBob.

 

Tunerpro seems good so far. I'm semi new to tuning and trying to learn all the jist while trying to get the most out of my hot rod. Can you explain the use of scalars? Obviously it's a set variable, but does the computer use that value to calculate what it needs to do? Such as injector lbs/hr. I just wanted to know the importance and possible destruction of my tune being wrong for the past few weeks.

 

Scalars are just individual values. They are used for a variety of uses, such as the injector flow rate that you found. Or a timer for a malfunction test, or the stoich AFR.

The flags are bit mapped parameters. There are 8 bits in a byte, so a single byte can have up to 8 flags in it. Each flag for a different function or feature.

The tables are multiple values. The spark advance and VE tables are the most changed for tuning.

RBob.