1227747 question

I started having issues months ago and after months of quietly researching through all of the awesome threads here I have decided to get the APU1 and start my journey into '7427. The only thing that has bothered me through my research is that I have never found a BCC that matches my setup. I have a 1990 G20 L05 MD8/MXO GU4. My ECM is a '7747 86ADSU 16139461 w/ EPROM ID 16060837. I looked through all of the 1990 BCCs with L05s and I found 4 that pertain to my vehichle. ANSY, ANSZ, ANTA, and ANTB. Which none of them had an EPROM that I do. Is this because of the 3.08 upgrade ? I've read that the '7427 runs better and the data logging is better so I have one on the way and plan on repinning it. When I flash it, should I use a '93-'94 L05 BCC ?

Other than that I plan on learning like we all do. I love this stuff ! :)

You will need to use a BIN that matches the PCM you will be using. The '7747 BIN will not work in the '7427.

There is a thread dedicated to the '7747 ECM: http://www.gearhead-efi.com/Fuel-Inj...Information-42

The 2nd generation '7427 TBI computer is an outstanding upgrade for a first generation '7747 TBI computer. (Homework Required)

Link to 16197427 (aka '7427) information: http://www.gearhead-efi.com/Fuel-Inj...Information-0D

dave w

Thanks fellas. I'm anxious to get started. Been reading up on putting a MAF in it.

Know anyone selling a APU1 ?

BFMF ... I can think of a few Acronyms to remember that

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Originally Posted by Jadgsxr

BFMF ... I can think of a few Acronyms to remember that

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Never mind. Looks like it'll be BJLF for me

Repinning to the '7427 wasn't that bad. It started running rough and I never did get it smooth last night. I have a '90 G20 Vin K, 700R4, 3.08s w/ hd springs. APU1, G1 adapter, using BJLF, I started with $OD and tried $OE. Seemed to run a little better with E. I read somewhere last night that it's possible that I should use the $31. Any thoughts ?

Also, I kept having odd events. One at a time and sporadic. Like, it would start missing and my spark advance was reading 3578%, then my MAP would peg 100 kg and it would puke and die, and for about 30-45 seconds both injector cycles were around 600%. Quirks ?

I followed the pinout chart from here and thirdgen. I used a S8011 and soldered ECM feed to KS out. Besides inspecting the harness and renewing the ground connections, nothing else was done.

I'm headed back out to try the $31 and eat some pizza.

Did you try $OD with fast 355 700r xdf.

Yes and I was mistaken earlier, it's Fast355's $od that's working better for me. I'm still goofing around with it though. Still not up to par. I'm about to do some more investigating on $31. Apparently it was made in '94-'95 for the 5.7 Ks that were deemed HD. Mine has RPOs that could have designated it HD. I'd really just like to know what the differences are between $OD and $31. Probably just fatter fuel tables down low.

I think $31 was for HD that had 4l80e trans. Are you using vss? Although there are work arounds od, oe and 31 won't be real happy without vss.

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Originally Posted by myburb

I think $31 was for HD that had 4l80e trans. Are you using vss? Although there are work arounds od, oe and 31 won't be real happy without vss.

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I don't. I've been doing my homework on them. I gather that the cable adapter type works best. I figured I could tune it to run/idle before working on the VSS part but, I've read in a few spots that it's best to get it in before tuning.

I went hunting and found another '7427 with a stock BCC BJLF. Had the MEMCAL too. So at least I know I am starting with a proper match with my mask. I think I am going to stick with the $OD. It seems to have the most options

Quote:

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Originally Posted by Jadgsxr

I don't. I've been doing my homework on them. I gather that the cable adapter type works best. I figured I could tune it to run/idle before working on the VSS part but, I've read in a few spots that it's best to get it in before tuning.

I went hunting and found another '7427 with a stock BCC BJLF. Had the MEMCAL too. So at least I know I am starting with a proper match with my mask. I think I am going to stick with the $OD. It seems to have the most options

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Stick with $0D, perhaps look at the timing table for BNKM which is the 1-ton 350/4L80E van. IIRC it is a $OE file.

As for the speed sensor the newer PCM only needs the speed signal input into the 2,000 ppm input if you are running without an E-trans. That means your vans stock VSS signal can be plugged right into the PCM and good to go. You need to disable the Computer Controlled Automatic flag in the options and Enable the TCC ONLY flag.

Thanks for the info ! I just about to take the VSS to the ECM. I ended up taking the passenger seat out and built a quick bench last night. Brought out a 40" screen and a desktop computer. I practiced a bunch with the emulator. Read a ton. Some of it is sinking in lol. I created around 10 bins last night using the compare tool. I did stick with $OD. Here's my concern though, and please correct me if I am off base but, I gather that all this centers down to the proper BCC for the proper ECM that is for the proper vehicle. Even filtered further primarily by engine type, trans type, gear ratio, weight, and emissions equipment. Am I doing wrong by using a bin made for a 4L60E ? The BJLF bin is 4L60E and 3.08 gears. No other bin mentions 3.08. I'm getting close to putting heads, T2, and a 750 on it :)

1990 G20 Model 21305. It's a Vin K. 6600 GVR. MD8 and it's a WBM model. It also has the GU4 which is the 3.08 and G50 which is the 3400# springs.

It had a 1227747 with ASDU. Now I have the 16197427 with BJLF out of a '94 Silverado 1500 5.7 LTR.

Well I figured out that I have a VSS and a DRAC, so that's cool. Should I take my A7 and put on E10 since I don't have the 4L80 ? There's a lot of debate on the F12 vs F13 as well, where should I put my A10 ?

Also, I stumbled across an old thread on here about using BJYL on a LO5 w/ a 700R4. I think it was Fast355 who said that there was no better BCC to use on a stock LO5 with a 700R4. What's the consensus on that ? I put one through the editor last night and I am about to try it out.

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Originally Posted by Fast355

You need to disable the Computer Controlled Automatic flag in the options

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I couldn't find this option. Am I going blind too ?


Attachment 13171

This is my pinout page from my 1990 Chevy G Body Wiring Diagram book. Might be handy to some. There's slight changes that are different from the 16197427 $OD pinout thread.

Attachment 13172

So now it starts and then shuts off immediately. When I unplug the MAP it stays running. Is the MAP bad ? I have 4 single bar MAPs and they all act the same. Am I missing something ? Could all 4 be bad ? Can I get rid of the MAP ? Is a MAF better ? I need to get this thing running. It is now the only vehicle I have :(