Moving from 1227747 What is the best TBI ECM to use?

**dave w** · 01-16-2022

1993 Pickups, Vans, and Suburban's with 4L60E Transmission also used PCM's (16168625) with the Red / Blue Connectors.

dave w

**stew86MCSS396** · 01-16-2022

Soooo happens I was given a Poncho 350 that supposedly has been gone through with new bearings/rings and a performance cam. Gonna attempt to run a TBI on top of Edelbrock spreadbore intake with an adapter. Have couple of Poncho HEIs here and still in the process/research of swapping out the guts from an Chevy EFI HEI into it. Another thing on the horizon is rebuilding a trans that has a BOP bellhousing which would be a CZF 200-4r. My feelings are torn on using the 427 although it's leap and bounds faster, so far I'm 0 for 2 using it to control TCC on a 700r4. I know you're using a manual trans so this is moot. I've read every possible thread about setting it up but can't seem to get it to work correctly. It's not that it's not working, it appears to lock up all the time as soon as it makes 1-2 shift. Right now using 4th gear pressure switch to energize TCC only in 4th but as soon as the 3-4 shift happens, it immediately locks up no matter what the speed is. I didn't do any of the wiring on either swaps but did double triple quadruple checked it to be correct. Whats weird is on the datalog, you can clearly see the TCC being commanded on/off at programmed speed but in reality that's not happening. It's like I have a internal short at all times. Sorry for the off topic rant... Speaking of red/blue connectors, you can still order them from Mouser...
http://gearhead-efi.com/Fuel-Injecti...CM-Plug-source

**tayto** · 01-18-2022

i would check your internal lockup harness in the trans and map it out. might need to find a different harness or rewire

**stew86MCSS396** · 01-19-2022

Dont see how that can be the problem when the tcc worked as advertised with the original ECM.

**tayto** · 01-19-2022

you talk about a 2004r, then a 700r4. you also never mentioned it worked before and now it doesn't. the 7427 will control a "lock up only" transmission (700r4/2004r). if it's locking up immediately as soon as you shift into 4th, then it's probably wired that way internally. OR you have the TCC signal wire grounded (check that its on the correct pin) most ECM controlled TCC have 3 wires power, tcc signal, and "high gear" switch aka 4th gear switch. there is no physical connection between the 4th gear switch and the tcc solenoid aside both housing being grounded.

**kilohertz** · 01-19-2022

Look what I found yesterday! The wrecker had over a dozen of these, had to decide which 2 I thought would be the best, this is the first standard BIN I have seen. I just need to find a complete harness and I can start the conversion.

Let the games begin....finally, I am moving into the 90's

cheers

**In-Tech** · 01-19-2022

If these files aren't already in the archives, please read both memcal's and post the .bin files :)

**kilohertz** · 01-20-2022

Will do. I looked in the archive and I didn't see either of these. I'll post them here and whoever knows how to get them to the archive can move them.

Cheers

**ScottP** · 01-20-2022

Great score - nice to see you're making progress.

You could post the BINs directly to the thread here:

http://www.gearhead-efi.com/Fuel-Inj...Information-0D

I suspect that's where the most folks would be able to find them.

-Scott

**kilohertz** · 01-20-2022

I was looking here... http://www.gearhead-efi.com/gearhead-efi/bin/

I will post them in the 7427 section as you mentioned. I just need to lift the lid and see what type of adapter I need to make, I should have the parts here to do it. I'll post when I get it figured out.

Cheers

**dave w** · 01-20-2022

BPRJ is a 1995 7.4 Liter with Manual. possibly $31 or possibly $OE? . . . defiantly a very cool .bin to add to the library!

BJYL is a 1995 5.7 Liter with a 4L60E, $OD

dave w

**kilohertz** · 01-20-2022

Originally Posted by dave w

BPRJ is a 1995 7.4 Liter with Manual. possibly $31 or possibly $OE? . . . defiantly a very cool .bin to add to the library!

BJYL is a 1995 5.7 Liter with a 4L60E, $OD

dave w

Thanks Dave!

I got the first EPROM out, the BJYL, started with that as there were lots of those, but only one of the BPRJ. I managed to extract it intact, guessing it's a 27C512??? All reference to MFR and part number are not printed on the EPROM, just date code of 9508.

Standby.

Cheers

**kilohertz** · 01-20-2022

I still am not sure what chip size it is but I was able to read it properly as a 27C512 and here it is. I'll let the more experienced folk check it out and confirm it's a good BIN file and I'll extract the 7.4 manual EPROM tomorrow. I loaded it into TunerPro RT with $OD and it looks like good data.

It's dinner and I need to light a fire...damn cold in here.

Cheers

**In-Tech** · 01-20-2022

The checksum(70BB) is correct so that file should be fine. Looks like a good read.

**kilohertz** · 01-21-2022

I decided to build a little adapter to allow me to read the EPROM while it is still mounted on the MEMCAL thus able to get a good BIN in case something goes south in the chip extraction. I can also use it for burning whatever chip I decide to use, undecided on that as my programmer won't do 27SF512. Looking for other options.

Here is the 7.4L Manual Transmission BIN file from the 7427 for the group to enjoy, I am not sure how to confirm checksum, maybe someone could tell me how to do it for future BINS. I also am posting a few pics of the little adapter I made, just a simple piece of cct brd with a little cut down the center to separate the 2 sides.

Cheers!

PS, extracted the second EPROM no problem, and both knock sensor hybrids. You can see one needs a pretty fine tip to get these out in one piece.